Aims. This study aimed to evaluate the clinical application of the PJI-TNM classification for periprosthetic joint infection (PJI) by determining intraobserver and interobserver reliability. To facilitate its use in clinical practice, an educational app was subsequently developed and evaluated. Methods. A total of ten orthopaedic surgeons classified 20 cases of PJI based on the PJI-TNM classification. Subsequently, the classification was re-evaluated using the PJI-TNM app. Classification accuracy was calculated separately for each subcategory (reinfection, tissue and implant condition, non-human cells, and morbidity of the patient). Fleiss’ kappa and Cohen’s kappa were calculated for interobserver and intraobserver reliability, respectively. Results. Overall, interobserver and intraobserver agreements were substantial across the 20 classified cases. Analyses for the variable ‘reinfection’ revealed an almost perfect interobserver and intraobserver agreement with a classification accuracy of 94.8%. The category 'tissue and implant conditions' showed moderate interobserver and substantial intraobserver reliability, while the classification accuracy was 70.8%. For 'non-human cells,' accuracy was 81.0% and interobserver agreement was moderate with an almost perfect intraobserver reliability. The classification accuracy of the variable 'morbidity of the patient' reached 73.5% with a moderate interobserver agreement, whereas the intraobserver agreement was substantial. The application of the app yielded comparable results across all subgroups. Conclusion. The PJI-TNM classification system captures the heterogeneity of PJI and can be applied with substantial inter- and intraobserver reliability. The PJI-TNM educational app aims to facilitate application in clinical practice. A major limitation was the correct assessment of the implant situation. To eliminate this, a re-evaluation according to intraoperative findings is strongly recommended. Cite this article: Bone Joint Res 2024;13(1):19–27

Aims. The aim of this study was to investigate the relationship between the Orthopaedic Trauma Society (OTS) classification of open fractures and economic costs. Methods. Resource use was measured during the six months that followed open fractures of the lower limb in 748 adults recruited as part of two large clinical trials within the UK Major Trauma Research Network. Resource inputs were valued using unit costs drawn from primary and secondary sources. Economic costs (GBP sterling, 2017 to 2018 prices), estimated from both a NHS and Personal Social Services (PSS) perspective, were related to the degree of complexity of the open fracture based on the OTS classification. Results. Adjusted mean total NHS and PSS costs were £13,785 following treatment of complex fractures and £3,550 following treatment of simple fractures, where the open fracture wound is closed at the end of the first wound debridement, generating a mean difference of £10,235 (95% confidence interval £8,074 to £12,396). Conclusion. Following previous work correlating clinical outcomes with the OTS classification of open fractures, this study suggests that the new OTS classification also correlates with economic costs estimated from alternative study perspectives. Cite this article: Bone Joint J 2022;104-B(3):408–412

Aims. The evidence demonstrating the superiority of early MRI has led to increased use of MRI in clinical pathways for acute wrist trauma. The aim of this study was to describe the radiological characteristics and the inter-observer reliability of a new MRI based classification system for scaphoid injuries in a consecutive series of patients. Methods. We identified 80 consecutive patients with acute scaphoid injuries at one centre who had presented within four weeks of injury. The radiographs and MRI scans were assessed by four observers, two radiologists, and two hand surgeons, using both pre-existing classifications and a new MRI based classification tool, the Oxford Scaphoid MRI Assessment Rating Tool (OxSMART). The OxSMART was used to categorize scaphoid injuries into three grades: contusion (grade 1); unicortical fracture (grade 2); and complete bicortical fracture (grade 3). Results. In total there were 13 grade 1 injuries, 11 grade 2 injuries, and 56 grade 3 injuries in the 80 consecutive patients. The inter-observer reliability of the OxSMART was substantial (Kappa = 0.711). The inter-observer reliability of detecting an obvious fracture was moderate for radiographs (Kappa = 0.436) and MRI (Kappa = 0.543). Only 52% (29 of 56) of the grade 3 injuries were detected on plain radiographs. There were two complications of delayed union, both of which occurred in patients with grade 3 injuries, who were promptly treated with cast immobilization. There were no complications in the patients with grade 1 and 2 injuries and the majority of these patients were treated with early mobilization as pain allowed. Conclusion. This MRI based classification tool, the OxSMART, is reliable and clinically useful in managing patients with acute scaphoid injuries. Cite this article: Bone Jt Open 2022;3(11):913–920

Aims. To describe a new objective classification for open fractures of the lower limb and to correlate the classification with patient-centred outcomes. Methods. The proposed classification was investigated within a cohort of adults with open fractures of the lower limb who were recruited as part of two large clinical trials within the UK Major Trauma Network. The classification was correlated with patient-reported Disability Rating Index (DRI) and EuroQol five-dimension questionnaire (EQ-5D) health-related quality of life in the year after injury, and with deep infection at 30 days, according to the Centers for Disease Control and Prevention definition of a deep surgical site infection. Results. A total of 748 participants were included in the analysis. Of these, 288 (38.5%) had a simple open fracture and 460 (61.5%) had a complex fracture as defined by the new classification system. At 12 months, the mean DRI in the simple fracture group was 32.5 (SD 26.8) versus 43.9 (SD 26.1) in the complex fracture group (odds ratio (OR) 8.19; 95% confidence interval (CI) 3.69 to 12.69). At 12 months the mean health-related quality of life (EQ-5D utility) in the simple fracture group was 0.59 (SD 0.29) versus 0.56 (SD 0.32) in the complex fracture group (OR -0.03; 95% CI -0.09 to 0.02). The differences in the rate of deep infection at 30 days was not statistically significant. Conclusion. The Orthopaedic Trauma Society open fracture classification is based upon objective descriptors of the injury and correlates with patient-centred outcomes in a large cohort of open fractures of the lower limb. Cite this article: Bone Joint J 2020;102-B(11):1469–1474

Aims. The morphology of medial malleolar fracture is highly variable and difficult to characterize without 3D reconstruction. There is also no universally accepeted classification system. Thus, we aimed to characterize fracture patterns of the medial malleolus and propose a classification scheme based on 3D CT reconstruction. Methods. We retrospectively reviewed 537 consecutive cases of ankle fractures involving the medial malleolus treated in our institution. 3D fracture maps were produced by superimposing all the fracture lines onto a standard template. We sliced fracture fragments and the standard template based on selected sagittal and coronal planes to create 2D fracture maps, where angles α and β were measured. Angles α and β were defined as the acute angles formed by the fracture line and the horizontal line on the selected planes. Results. A total of 121 ankle fractures were included. We revealed several important fracture features, such as a high correlation between posterior collicular fractures and posteromedial fragments. Moreover, we generalized the fracture geometry into three recurrent patterns on the coronal view of 3D maps (transverse, vertical, and irregular) and five recurrent patterns on the lateral view (transverse, oblique, vertical, Y-shaped, and irregular). According to the fracture geometry on the coronal and lateral view of 3D maps, we subsequently categorized medial malleolar fractures into six types based on the recurrent patterns: anterior collicular fracture (27 type I, 22.3%), posterior collicular fracture (12 type II, 9.9%), concurrent fracture of anterior and posterior colliculus (16 type III, 13.2%), and supra-intercollicular groove fracture (66 type IV, 54.5%). Therewere three variants of type IV fractures: transverse (type IVa), vertical (type IVb), and comminuted fracture (type IVc). The angles α and β varied accordingly. Conclusion. Our findings yield insight into the characteristics and recurrent patterns of medial malleolar fractures. The proposed classification system is helpful in understanding injury mechanisms and guiding diagnosis, as well as surgical strategies. Cite this article: Bone Joint J 2021;103-B(5):931–938

Objectives. The aim of this study was to assess the clinical application of, and optimize the variables used in, the BACH classification of long-bone osteomyelitis. Methods. A total of 30 clinicians from a variety of specialities classified 20 anonymized cases of long-bone osteomyelitis using BACH. Cases were derived from patients who presented to specialist centres in the United Kingdom between October 2016 and April 2017. Accuracy and Fleiss’ kappa (Fκ) were calculated for each variable. Bone involvement (B-variable) was assessed further by nine clinicians who classified ten additional cases of long bone osteomyelitis using a 3D clinical imaging package. Thresholds for defining multidrug-resistant (MDR) isolates were optimized using results from a further analysis of 253 long bone osteomyelitis cases. Results. The B-variable had a classification accuracy of 77.0%, which improved to 95.7% when using a 3D clinical imaging package (p < 0.01). The A-variable demonstrated difficulty in the accuracy of classification for increasingly resistant isolates (A1 (non-resistant), 94.4%; A2 (MDR), 46.7%; A3 (extensively or pan-drug-resistant), 10.0%). Further analysis demonstrated that isolates with four or more resistant test results or less than 80% sensitive susceptibility test results had a 98.1% (95% confidence interval (CI) 96.6 to 99.6) and 98.8% (95% CI 98.1 to 100.0) correlation with MDR status, respectively. The coverage of the soft tissues (C-variable) and the host status (H-variable) both had a substantial agreement between users and a classification accuracy of 92.5% and 91.2%, respectively. Conclusions. The BACH classification system can be applied accurately by users with a variety of clinical backgrounds. Accuracy of B-classification was improved using 3D imaging. The use of the A-variable has been optimized based on susceptibility testing results. Cite this article: A. J. Hotchen, M. Dudareva, J. Y. Ferguson, P. Sendi, M. A. McNally. The BACH classification of long bone osteomyelitis. Bone Joint Res 2019;8:459–468. DOI: 10.1302/2046-3758.810.BJR-2019-0050.R1

Aims. Joint registries classify all further arthroplasty procedures to a knee with an existing partial arthroplasty as revision surgery, regardless of the actual procedure performed. Relatively minor procedures, including bearing exchanges, are classified in the same way as major operations requiring augments and stems. A new classification system is proposed to acknowledge and describe the detail of these procedures, which has implications for risk, recovery, and health economics. Methods. Classification categories were proposed by a surgical consensus group, then ranked by patients, according to perceived invasiveness and implications for recovery. In round one, 26 revision cases were classified by the consensus group. Results were tested for inter-rater reliability. In round two, four additional cases were added for clarity. Round three repeated the survey one month later, subject to inter- and intrarater reliability testing. In round four, five additional expert partial knee arthroplasty surgeons were asked to classify the 30 cases according to the proposed revision partial knee classification (RPKC) system. Results. Four classes were proposed: PR1, where no bone-implant interfaces are affected; PR2, where surgery does not include conversion to total knee arthroplasty, for example, a second partial arthroplasty to a native compartment; PR3, when a standard primary total knee prosthesis is used; and PR4 when revision components are necessary. Round one resulted in 92% inter-rater agreement (Kendall’s W 0.97; p < 0.005), rising to 93% in round two (Kendall’s W 0.98; p < 0.001). Round three demonstrated 97% agreement (Kendall’s W 0.98; p < 0.001), with high intra-rater reliability (interclass correlation coefficient (ICC) 0.99; 95% confidence interval 0.98 to 0.99). Round four resulted in 80% agreement (Kendall’s W 0.92; p < 0.001). Conclusion. The RPKC system accounts for all procedures which may be appropriate following partial knee arthroplasty. It has been shown to be reliable, repeatable and pragmatic. The implications for patient care and health economics are discussed. Cite this article: Bone Jt Open 2021;2(8):638–645

Aims. The aim of the current study was to assess the reliability of the Ottawa classification for symptomatic acetabular dysplasia. Methods. In all, 134 consecutive hips that underwent periacetabular osteotomy were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior, or posterior. A total of 74 cases were selected for reliability analysis, and these included 44 dysplastic and 30 normal hips. A group of six blinded fellowship-trained raters, provided with the classification system, looked at these radiographs at two separate timepoints to classify the hips using standard radiological measurements. Thereafter, a consensus meeting was held where a modified flow diagram was devised, before a third reading by four raters using a separate set of 74 radiographs took place. Results. Intrarater results per surgeon between Time 1 and Time 2 showed substantial to almost perfect agreement among the raters (κappa = 0.416 to 0.873). With respect to inter-rater reliability, at Time 1 and Time 2 there was substantial agreement overall between all surgeons (Time 1 κappa = 0.619; Time 2 κappa = 0.623). Posterior and anterior rating categories had moderate and fair agreement at Time 1 (posterior κappa = 0.557; anterior κappa = 0.438) and Time 2 (posterior κappa = 0.506; anterior κappa = 0.250), respectively. At Time 3, overall reliability (κappa = 0.687) and posterior and anterior reliability (posterior κappa = 0.579; anterior κappa = 0.521) improved from Time 1 and Time 2. Conclusion. The Ottawa classification system provides a reliable way to identify three categories of acetabular dysplasia that are well-aligned with surgical management. The term ‘borderline dysplasia’ should no longer be used. Cite this article: Bone Joint Res. 2020;9(5):242–249

Aims. Although knee osteoarthritis (OA) is diagnosed and monitored radiologically, actual full-thickness cartilage loss (FTCL) has rarely been correlated with radiological classification. This study aims to analyze which classification system correlates best with FTCL and to assess their reliability. Methods. A prospective study of 300 consecutive patients undergoing unilateral total knee arthroplasty (TKA) for OA (mean age 69 years (44 to 91; standard deviation (SD) 9.5), 178 (59%) female). Two blinded examiners independently graded preoperative radiographs using five common systems: Kellgren-Lawrence (KL); International Knee Documentation Committee (IKDC); Fairbank; Brandt; and Ahlbäck. Interobserver agreement was assessed using the intraclass correlation coefficient (ICC). Intraoperatively, anterior cruciate ligament (ACL) status and the presence of FTCL in 16 regions of interest were recorded. Radiological classification and FTCL were correlated using the Spearman correlation coefficient. Results. Knees had a mean of 6.8 regions of FTCL (SD 3.1), most common medially. The commonest patterns of FTCL were medial ± patellofemoral (143/300, 48%) and tricompartmental (89/300, 30%). ACL status was associated with pattern of FTCL (p = 0.023). All radiological classification systems demonstrated moderate ICC, but this was highest for the IKDC: whole knee 0.68 (95% confidence interval (CI) 0.60 to 0.74); medial compartment 0.84 (95% CI 0.80 to 0.87); and lateral compartment 0.79 (95% CI 0.73 to 0.83). Correlation with actual FTCL was strongest for Ahlbäck (Spearman rho 0.27 to 0.39) and KL (0.30 to 0.33) systems, although all systems demonstrated medium correlation. The Ahlbäck score was the most discriminating in severe knee OA. Osteophyte presence in the medial compartment had high positive predictive value (PPV) for FTCL, but not in the lateral compartment. Conclusion. The Ahlbäck and KL systems had the highest correlation with confirmed cartilage loss at TKA. However, the IKDC system displayed the best interobserver reliability, with favourable correlation with FTCL in medial and lateral compartments, although it was less discriminating in more severe disease. Cite this article: Bone Joint J 2020;102-B(3):301–309

Aims. There has been a recent resurgence in interest in combined partial knee arthroplasty (PKA) as an alternative to total knee arthroplasty (TKA). The varied terminology used to describe these procedures leads to confusion and ambiguity in communication between surgeons, allied health professionals, and patients. A standardized classification system is required for patient safety, accurate clinical record-keeping, clear communication, correct coding for appropriate remuneration, and joint registry data collection. Materials and Methods. An advanced PubMed search was conducted, using medical subject headings (MeSH) to identify terms and abbreviations used to describe knee arthroplasty procedures. The search related to TKA, unicompartmental (UKA), patellofemoral (PFA), and combined PKA procedures. Surveys were conducted of orthopaedic surgeons, trainees, and biomechanical engineers, who were asked which of the descriptive terms and abbreviations identified from the literature search they found most intuitive and appropriate to describe each procedure. The results were used to determine a popular consensus. Results. Survey participants preferred “bi-unicondylar arthroplasty” (Bi-UKA) to describe ipsilateral medial and lateral unicompartmental arthroplasty; “medial bi-compartmental arthroplasty” (BCA-M) to describe ipsilateral medial unicompartmental arthroplasty with patellofemoral arthroplasty; “lateral bi-compartmental arthroplasty” (BCA-L) to describe ipsilateral lateral unicompartmental arthroplasty with patellofemoral arthroplasty; and tri-compartmental arthroplasty (TCA) to describe ipsilateral patellofemoral and medial and lateral unicompartmental arthroplasties. “Combined partial knee arthroplasty” (CPKA) was the favoured umbrella term. Conclusion. We recommend bi-unicondylar arthroplasty (Bi-UKA), medial bicompartmental arthroplasty (BCA-M), lateral bicompartmental arthroplasty (BCA-L), and tricompartmental arthroplasty (TCA) as the preferred terms to classify CPKA procedures. Cite this article: Bone Joint J 2019;101-B:922–928

The most widely used classification system for acetabular fractures was developed by Judet, Judet and Letournel over 50 years ago primarily to aid surgical planning. As population demographics and injury mechanisms have altered over time, the fracture patterns also appear to be changing. We conducted a retrospective review of the imaging of 100 patients with a mean age of 54.9 years (19 to 94) and a male to female ratio of 69:31 seen between 2010 and 2013 with acetabular fractures in order to determine whether the current spectrum of injury patterns can be reliably classified using the original system. Three consultant pelvic and acetabular surgeons and one senior fellow analysed anonymous imaging. Inter-observer agreement for the classification of fractures that fitted into defined categories was substantial, (κ = 0.65, 95% confidence interval (CI) 0.51 to 0.76) with improvement to near perfect on inclusion of CT imaging (κ = 0.80, 95% CI 0.69 to 0.91). However, a high proportion of injuries (46%) were felt to be unclassifiable by more than one surgeon; there was moderate agreement on which these were (κ = 0.42 95% CI 0.31 to 0.54). Further review of the unclassifiable fractures in this cohort of 100 patients showed that they tended to occur in an older population (mean age 59.1 years; 22 to 94 vs 47.2 years; 19 to 94; p = 0.003) and within this group, there was a recurring pattern of anterior column and quadrilateral plate involvement, with or without an incomplete posterior element injury. . Cite this article: Bone Joint J 2015;97-B:1139–43

Aims. Fractures of the navicular can occur in isolation but, owing to the intimate anatomical and biomechanical relationships, are often associated with other injuries to the neighbouring bones and joints in the foot. As a result, they can lead to long-term morbidity and poor function. Our aim in this study was to identify patterns of injury in a new classification system of traumatic fractures of the navicular, with consideration being given to the commonly associated injuries to the midfoot. Patients and Methods. We undertook a retrospective review of 285 consecutive patients presenting over an eight- year period with a fracture of the navicular. Five common patterns of injury were identified and classified according to the radiological features. Type 1 fractures are dorsal avulsion injuries related to the capsule of the talonavicular joint. Type 2 fractures are isolated avulsion injuries to the tuberosity of the navicular. Type 3 fractures are a variant of tarsometatarsal fracture/dislocations creating instability of the medial ray. Type 4 fractures involve the body of the navicular with no associated injury to the lateral column and type 5 fractures occur in conjunction with disruption of the midtarsal joint with crushing of the medial or lateral, or both, columns of the foot. Results. In order to test the reliability and reproducibility of this new classification, a cohort of 30 patients with a fracture of the navicular were classified by six independent assessors at two separate times, six months apart. Interobserver reliability and intraobserver reproducibility both had substantial agreement, with kappa values of 0.80 and 0.72, respectively. Conclusion. We propose a logical, all-inclusive, and mutually exclusive classification system for fractures of the navicular that gives associated injuries involving the lateral column due consideration. We have shown that this system is reliable and reproducible and have described the rationale for the subsequent treatment of each type. Cite this article: Bone Joint J 2018;100-B:176–82

In this study, we describe a morphological classification for greater tuberosity fractures of the proximal humerus. We divided these fractures into three types: avulsion, split and depression. We retrospectively reviewed all shoulder radiographs showing isolated greater tuberosity fractures in a Level I trauma centre between July 2007 and July 2012. We identified 199 cases where records and radiographs were reviewed and included 79 men and 120 women with a mean age of 58 years (23 to 96). The morphological classification was applied to the first 139 cases by three reviewers on two occasions using the Kappa statistic and compared with the AO and Neer classifications. The inter- and intra-observer reliability of the morphological classification was 0.73 to 0.77 and 0.69 to 0.86, respectively. This was superior to the Neer (0.31 to 0.35/0.54 to 0.63) and AO (0.30 to 0.32/0.59 to 0.65) classifications. The distribution of avulsion, split and depression type fractures was 39%, 41%, and 20%, respectively. This classification of greater tuberosity fractures is more reliable than the Neer or AO classifications. These distinct fracture morphologies are likely to have implications in terms of pathophysiology and surgical technique. Cite this article: Bone Joint J 2014;96-B:646–51

It is probable that both genetic and environmental factors play some part in the aetiology of most cases of degenerative hip disease. Geneticists have identified some single gene disorders of the hip, but have had difficulty in identifying the genetics of many of the common causes of degenerative hip disease. The heterogeneity of the phenotypes studied is part of the problem. A detailed classification of phenotypes is proposed. This study is based on careful documentation of 2003 consecutive total hip replacements performed by a single surgeon between 1972 and 2000. The concept that developmental problems may initiate degenerative hip disease is supported. The influences of gender, age and body mass index are outlined. Biomechanical explanations for some of the radiological appearances encountered are suggested. The body weight lever, which is larger than the abductor lever, causes the abductor power to be more important than body weight. The possibility that a deficiency in joint lubrication is a cause of degenerative hip disease is discussed. Identifying the phenotypes may help geneticists to identify genes responsible for degenerative hip disease, and eventually lead to a definitive classification

We describe the routine imaging practices of Level 1 trauma centres for patients with severe pelvic ring fractures, and the interobserver reliability of the classification systems of these fractures using plain radiographs and three-dimensional (3D) CT reconstructions. Clinical and imaging data for 187 adult patients (139 men and 48 women, mean age 43 years (15 to 101)) with a severe pelvic ring fracture managed at two Level 1 trauma centres between July 2007 and June 2010 were extracted. Three experienced orthopaedic surgeons classified the plain radiographs and 3D CT reconstruction images of 100 patients using the Tile/AO and Young–Burgess systems. Reliability was compared using kappa statistics. A total of 115 patients (62%) had plain radiographs as well as two-dimensional (2D) CT and 3D CT reconstructions, 52 patients (28%) had plain films only, 12 (6.4%) had 2D and 3D CT reconstructions images only, and eight patients (4.3%) had no available images. The plain radiograph was limited to an anteroposterior pelvic view. Patients without imaging, or only plain films, were more severely injured. A total of 72 patients (39%) were imaged with a pelvic binder in situ. Interobserver reliability for the Tile/AO (Kappa 0.10 to 0.17) and Young–Burgess (Kappa 0.09 to 0.21) was low, and insufficient for clinical and research purposes. Severe pelvic ring fractures are difficult to classify due to their complexity, the increasing use of early treatment such as with pelvic binders, and the absence of imaging altogether in important patient sub-groups, such as those who die early of their injuries. Cite this article: Bone Joint J 2013;95-B:1396–1401

Periprosthetic fractures are an increasingly common complication following joint replacement. The principles which underpin their evaluation and treatment are common across the musculoskeletal system. The Unified Classification System proposes a rational approach to treatment, regardless of the bone that is broken or the joint involved. Cite this article: Bone Joint J 2014;96-B:713–16

Aims. Classifying trochlear dysplasia (TD) is useful to determine the treatment options for patients suffering from patellofemoral instability (PFI). There is no consensus on which classification system is more reliable and reproducible for the purpose of guiding clinicians’ management of PFI. There are also concerns about the validity of the Dejour Classification (DJC), which is the most widely used classification for TD, having only a fair reliability score. The Oswestry-Bristol Classification (OBC) is a recently proposed system of classification of TD, and the authors report a fair-to-good interobserver agreement and good-to-excellent intraobserver agreement in the assessment of TD. The aim of this study was to compare the reliability and reproducibility of these two classifications. Methods. In all, six assessors (four consultants and two registrars) independently evaluated 100 axial MRIs of the patellofemoral joint (PFJ) for TD and classified them according to OBC and DJC. These assessments were again repeated by all raters after four weeks. The inter- and intraobserver reliability scores were calculated using Cohen’s kappa and Cronbach’s α. Results. Both classifications showed good to excellent interobserver reliability with high α scores. The OBC classification showed a substantial intraobserver agreement (mean kappa 0.628; p < 0.005) whereas the DJC showed a moderate agreement (mean kappa 0.572; p < 0.005). There was no significant difference in the kappa values when comparing the assessments by consultants with those by registrars, in either classification system. Conclusion. This large study from a non-founding institute shows both classification systems to be reliable for classifying TD based on axial MRIs of the PFJ, with the simple-to-use OBC having a higher intraobserver reliability score than that of the DJC. Cite this article: Bone Jt Open 2023;4(7):532–538

Abstract. Purpose. Intracanal rib head penetration is a well-known entity in dystrophic scoliotic curves in neurofibromatosis type 1. There is potential for spinal cord injury if this is not recognised and managed appropriately. No current CT-based classification system is currently in use to quantify rib head penetration. This study aims to propose and evaluate a novel CT-based classification for rib head penetration primarily for neurofibromatosis but which can also be utilised in other conditions of rib head penetration. Materials and methods. The grading was developed as four grades: normal rib head (RH) position—Grade 0, subluxed ext-racanal RH position—Grade 1, RH at pedicle—Grade 2, intracanal RH—Grade 3. Grade 3 was further classified depending on the head position in the canal divided into thirds. Rib head penetration into proximal third (from ipsilateral side)—Grade 3A, into the middle third—Grade 3B and into the distal third—Grade 3C. Seventy-five axial CT images of Neurofibromatosis Type 1 patients in the paediatric age group were reviewed by a radiologist and a spinal surgeon independently to assess interobserver and intraobserver agreement of the novel CT classification. Agreement analysis was performed using the weighted Kappa statistic. Results. There was substantial interobserver correlation with mean Kappa score (k = 0.8, 95% CI 0.7–0.9) and near perfect intraobserver Kappa of 1.0 (95% CI 0.9–1.0) and 0.9 (95% CI 0.9–1.0) for the two readers. Conclusion. The novel CT-based classification quantifies rib head penetration which aids in management planning

Classifying trochlear dysplasia (TD) is useful to determine the treatment options for patients suffering from patellofemoral instability (PFI). There is no consensus on which classification system is more reliable and reproducible for this purpose to guide clinicians in order to treat PFI. There are also concerns about validity of the Dejour classification (DJC), which is the most widely used classification for TD, having only a fair reliability score. The Oswestry-Bristol classification (OBC) is a recently proposed system of classification of TD and the authors report a fair-to-good interobserver agreement and good-to-excellent intra-observer agreement in the assessment of TD. The aim of this study was to compare the reliability and reproducibility of these two classifications. 6 assessors (4 consultants and 2 registrars) independently evaluated 100 magnetic resonance axial images of the patella-femoral joint for TD and classified them according to OBC and DJC. These assessments were again repeated by all raters after 4 weeks. The inter and intra-observer reliability scores were calculated using Cohen's kappa and Cronbach's alpha. Both classifications showed good to excellent interobserver reliability with high alpha scores. The OBC classification showed a substantial intra-observer agreement (mean kappa 0.628)[p<0.005] whereas the DJC showed a moderate agreement (mean kappa 0.572) [p<0.005]. There was no significant difference in the kappa values when comparing the assessments by consultants to those by registrars, in either classification systems. This large study from a non-founding institute shows both classification systems to be reliable for classifying TD based on magnetic resonance axial images of the patella-femoral joint, with the simple to use OBC having a higher intra-observer reliability score compared to the DJC

Abstract. Purpose. No clinical CT based classification system is currently in use for Lumbar Foraminal Stenosis. MRI scanners are not easily available, are expensive and may be contraindicated in an increasing number of patients. This study aims to propose and evaluate the reproducibility of a novel CT based classification for lumbar foraminal stenosis. Materials and Methods. The grading was developed as 4 grades. Normal foramen – Grade 0, Anteroposterior(AP)/Superoinferior (SI)(single plane) fat compression – Grade 1, Both AP/SI compression (two planes) – Grade 2 (both AP and SI) without distortion of nerve root, Grade 2 with distortion of nerve root – Grade 3. 800 lumbar foramen of a cohort of 100 random patients over the age of 60 who had undergone both CT and MRI scans were reviewed by two radiologists independently to assess agreement of the novel CT classification against the MRI based grading system of Lee et al. Interobserver(n=400) and intraobserver agreement(n=160) was also evaluated. Agreement analysis was performed using the Weighted Kappa statistic. Results. 100 patients (M:F = 45:55) with a mean age of 68.5 years (range 60 – 83 years were included in the study. The duration between CT and MRI scans was 98 days(range 0 – 540, SD – 108). There was good correlation between CT and MRI with Kappa scores (k=0.81) and intraobserver Kappa of 0.89 and 0.98 for the two readers. Conclusion. The novel CT based classification correlates well with the MRI grading system and can safely and accurately replace it where required

Aim. To classify Fracture-related Infection (FRI) allowing comparison of clinical studies and to guide decision-making around the main surgical treatment concepts. Method. An international group of FRI experts met in Lisbon, June 2022 and proposed a new FRI classification. A core group met during the EBJIS Meeting in Graz, 2022 and on-line, to determine the preconditions, purpose, primary factors for inclusion, format and the detailed description of the elements of an FRI Classification. Results. Historically, FRI was classified by time from injury alone (early, delayed or late). Time produces pathophysiological changes which affect the bone, the soft-tissues and the patient general health, over a continuum. No definitive cut-off is therefore possible. Also, in several studies, time was not identified as an independent predictor of outcome. The most important primary factors were characteristics of the fracture (F), relevant systemic co-morbidities of the patient (R) and impairment of the soft-tissue envelope (I). These factors determine FRI severity, choice of treatment method and are predictors of outcome. For the fracture (F), the state of healing, the potential for bone healing and the presence or absence of a bone defect are critical factors. Co-morbidities are listed and the degree of end-organ damage is important (R). The ability to close the wound directly or the need for soft tissue reconstruction determines the impairment of the soft tissue component (I). Hence the FRI Classification was designed. The final proposal of the FRI Classification is presented here. The new classification has five stages; from simple cases of infected healed fractures, in healthy individuals with good soft tissues (Stage 1), through unhealed fractures with variable potential for bone healing (Stages 2, 3 or 4) to Stage 5, with no limb-sparing or reconstructive options. For instance, the need for a free flap (I4), over a well-healed fracture (F1), in a patient with 2 co-morbidities (R2) gives a classification of F1R2I4 for that patient. Conclusions. This novel approach to FRI classification builds on previous work in osteomyelitis, PJI and chronic medical conditions. It focusses attention on the elements of the disease which need treatment. It now requires validation in large patient cohorts. On behalf of the FRI Classification Consensus Group

Aims. The Coronal Plane Alignment of the Knee (CPAK) classification is a simple and comprehensive system for predicting pre-arthritic knee alignment. However, when the CPAK classification is applied in the Asian population, which is characterized by more varus and wider distribution in lower limb alignment, modifications in the boundaries of arithmetic hip-knee-ankle angle (aHKA) and joint line obliquity (JLO) should be considered. The purposes of this study were as follows: first, to propose a modified CPAK classification based on the actual joint line obliquity (aJLO) and wider range of aHKA in the Asian population; second, to test this classification in a cohort of Asians with healthy knees; third, to propose individualized alignment targets for different CPAK types in kinematically aligned (KA) total knee arthroplasty (TKA). Methods. The CPAK classification was modified by changing the neutral boundaries of aHKA to 0° ± 3° and using aJLO as a new variable. Radiological analysis of 214 healthy knees in 214 Asian individuals was used to assess the distribution and mean value of alignment angles of each phenotype among different classifications based on the coronal plane. Individualized alignment targets were set according to the mean lateral distal femoral angle (LDFA) and medial proximal tibial angle (MPTA) of different knee types. Results. A very high concentration, 191 from 214 individuals (89.3%), were found in knee types with apex distal JLO when the CPAK classification was applied in the Asian population. By using aJLO as a new variable, the high distribution percentage in knee types with apex distal JLO decreased to 125 from 214 individuals (58.4%). The most common types in order were Type II (n = 70; 32.7%), Type V (n = 55; 25.7%), and Type I (n = 46; 21.5%) in the modified CPAK classification. Conclusion. The modified CPAK classification corrected the uneven distribution when applying the CPAK classification in the Asian population. Setting individualized TKA alignment targets according to CPAK type may be a practical method to recreate optimal LDFA and MPTA in KA-TKA. Cite this article: Bone Jt Open 2022;3(3):211–217

Aims. The aim of this modified Delphi process was to create a structured Revision Hip Complexity Classification (RHCC) which can be used as a tool to help direct multidisciplinary team (MDT) discussions of complex cases in local or regional revision networks. Methods. The RHCC was developed with the help of a steering group and an invitation through the British Hip Society (BHS) to members to apply, forming an expert panel of 35. We ran a mixed-method modified Delphi process (three rounds of questionnaires and one virtual meeting). Round 1 consisted of identifying the factors that govern the decision-making and complexities, with weighting given to factors considered most important by experts. Participants were asked to identify classification systems where relevant. Rounds 2 and 3 focused on grouping each factor into H1, H2, or H3, creating a hierarchy of complexity. This was followed by a virtual meeting in an attempt to achieve consensus on the factors which had not achieved consensus in preceding rounds. Results. The expert group achieved strong consensus in 32 out of 36 factors following the Delphi process. The RHCC used the existing Paprosky (acetabulum and femur), Unified Classification System, and American Society of Anesthesiologists (ASA) classification systems. Patients with ASA grade III/IV are recognized with a qualifier of an asterisk added to the final classification. The classification has good intraobserver and interobserver reliability with Kappa values of 0.88 to 0.92 and 0.77 to 0.85, respectively. Conclusion. The RHCC has been developed through a modified Delphi technique. RHCC will provide a framework to allow discussion of complex cases as part of a local or regional hip revision MDT. We believe that adoption of the RHCC will provide a comprehensive and reproducible method to describe each patient’s case with regard to surgical complexity, in addition to medical comorbidities that may influence their management. Cite this article: Bone Jt Open 2022;3(5):423–431

Dysmorphic pelves are a known risk factor for malpositioned iliosacral screws. Improved understanding of pelvic morphology will minimise the risk of screw misplacement, neurovascular injuries and failed fixation. Existing classifications for sacral anatomy are complex and impractical for clinical use. We propose a CT-based classification using variations in pelvic anatomy to predict the availability of transosseous corridors across the sacrum. The classification aims to refine surgical planning which may reduce the risk of surgical complications. The authors postulated 4 types of pelves. The “superior most point of the sacroiliac joint” (sSIJ) typically corresponds with the mid-lower half of the L5 vertebral body. Hence, “the anterior cortex of L5” (L5. a. ) was divided to reference 3 distinct pelvic groups. A 4. th. group is required to represent pelves with a lumbosacral transitional vertebra. The proposed classification:. A – sSIJ is above the midpoint of L5. a. B – sSIJ is between the midpoint and the lowest point of L5. a. C – sSIJ is below the lowest point of L5. a. D – pelves with a lumbosacral transitional vertebra. Specific measures such as the width of the S1 and S2 axial and coronal corridors and the S1 lateral mass angles were used to differentiate between pelvic types. Three-hundred pelvic CT scans were classified into their respective types. Analysis of the specific measures mentioned above illustrated the significant difference between each pelvic type. Changes in the size of S1 and S2 axial corridors formed a pattern that was unique for each pelvic type. The intra- and inter-observer ratings were 0.97 and 0.95 respectively. Distinct relationships between the sizes of S1 and S2 axial corridors informed our recommendations on trans-sacral or iliosacral fixation, number and orientation of screws for each pelvic type. This classification utilises variations in the posterior pelvic ring to offer a planning guide for the insertion of iliosacral screws

Distal radius fractures (DRFs) are one of the most common types of fracture and one which is often treated surgically. Standard X-rays are obtained for DRFs, and in most cases that have an intra-articular component, a routine CT is also performed. However, it is estimated that CT is only required in 20% of cases and therefore routine CT's results in the overutilisation of resources burdening radiology and emergency departments. In this study, we explore the feasibility of using deep learning to differentiate intra- and extra-articular DRFs automatically and help streamline which fractures require a CT. Retrospectively x-ray images were retrieved from 615 DRF patients who were treated with an ORIF at the Royal Brisbane and Women's Hospital. The images were classified into AO Type A, B or C fractures by three training registrars supervised by a consultant. Deep learning was utilised in a two-stage process: 1) localise and focus the region of interest around the wrist using the YOLOv5 object detection network and 2) classify the fracture using a EfficientNet-B3 network to differentiate intra- and extra-articular fractures. The distal radius region of interest (ROI) detection stage using the ensemble model of YOLO networks detected all ROIs on the test set with no false positives. The average intersection over union between the YOLO detections and the ROI ground truth was Error! Digit expected.. The DRF classification stage using the EfficientNet-B3 ensemble achieved an area under the receiver operating characteristic curve of 0.82 for differentiating intra-articular fractures. The proposed DRF classification framework using ensemble models of YOLO and EfficientNet achieved satisfactory performance in intra- and extra-articular fracture classification. This work demonstrates the potential in automatic fracture characterization using deep learning and can serve to streamline decision making for axial imaging helping to reduce unnecessary CT scans

Aims. Trochlear dysplasia is a significant risk factor for patellofemoral instability. The Dejour classification is currently considered the standard for classifying trochlear dysplasia, but numerous studies have reported poor reliability on both plain radiography and MRI. The severity of trochlear dysplasia is important to establish in order to guide surgical management. We have developed an MRI-specific classification system to assess the severity of trochlear dysplasia, the Oswestry-Bristol Classification (OBC). This is a four-part classification system comprising normal, mild, moderate, and severe to represent a normal, shallow, flat, and convex trochlear, respectively. The purpose of this study was to assess the inter- and intraobserver reliability of the OBC and compare it with that of the Dejour classification. Methods. Four observers (two senior and two junior orthopaedic surgeons) independently assessed 32 CT and axial MRI scans for trochlear dysplasia and classified each according to the OBC and the Dejour classification systems. Assessments were repeated following a four-week interval. The inter- and intraobserver agreement was determined by using Fleiss’ generalization of Cohen’s kappa statistic and S-statistic nominal and linear weights. Results. The OBC showed fair-to-good interobserver agreement and good-to-excellent intraobserver agreement (mean kappa 0.68). The Dejour classification showed poor interobserver agreement and fair-to-good intraobserver agreement (mean kappa 0.52). Conclusion. The OBC can be used to assess the severity of trochlear dysplasia. It can be applied in clinical practice to simplify and standardize surgical decision-making in patients with recurrent patella instability. Cite this article: Bone Joint J 2020;102-B(1):102–107

The Revision Hip Complexity Classification (RHCC) was developed by modified Delphi system in 2022 to provide a comprehensive, reproducible framework for the multidisciplinary discussion of complex revision hip surgery. The aim of this study was to assess the validity, intra-relater and inter-relater reliability of the RHCC. Radiographs and clinical vignettes of 20 consecutive patients who had undergone revision of Total Hip Arthroplasty (THA) at our unit during the previous 12-month period were provided to observers. Five observers, comprising 3 revision hip consultants, 1 hip fellow and 1 ST3-8 registrar were familiarised with the RHCC. Each revision THA case was classified on two separate occasions by each observer, with a mean time between assessments of 42.6 days (24–57). Inter-observer reliability was assessed using the Fleiss™ Kappa statistic and percentage agreement. Intra-observer reliability was assessed using the Cohen Kappa statistic. Validity was assessed using percentage agreement and Cohen Kappa comparing observers to the RHCC web-based application result. All observers were blinded to patient notes, operation notes and post-operative radiographs throughout the process. Inter-observer reliability showed fair agreement in both rounds 1 and 2 of the survey (0.296 and 0.353 respectively), with a percentage agreement of 69% and 75%. Inter-observer reliability was highest in H3-type revisions with kappa values of 0.577 and 0.441. Mean intra-observer reliability showed moderate agreement with a kappa value of 0.446 (0.369 to 0.773). Validity percentage agreement was 44% and 39% respectively, with mean kappa values of 0.125 and 0.046 representing only slight agreement. This study demonstrates that classification using the RHCC without utilisation of the web-based application is unsatisfactory, showing low validity and reliability. Reliability was higher for more complex H3-type cases. The use of the RHCC web app is recommended to ensure the accurate and reliable classification of revision THA cases

Variations in pelvic anatomy are a major risk factor for misplaced percutaneous sacroiliac screws used to treat unstable posterior pelvic ring injuries. A better understanding of pelvic morphology improves preoperative planning and therefore minimises the risk of malpositioned screws, neurological or vascular injuries, failed fixation or malreduction. Hence a classification system which identifies the clinically important anatomical variations of the sacrum would improve communication among pelvic surgeons and inform treatment strategy. 300 Pelvic CT scans from skeletally mature trauma patients that did not have pre-existing posterior pelvic pathology were identified. Axial and coronal transosseous corridor widths at both S1 and S2 were recorded. Additionally, the S1 lateral mass angle were also calculated. Pelvises were classified based upon the sacroiliac joint (SIJ) height using the midpoint of the anterior cortex of L5 as a reference point. Four distinct types could be identified:. Type-A – SIJ height is above the midpoint of the anterior cortex of the L5 vertebra. Type-B – SIJ height is between the midpoint and the lowest point of the anterior cortex of the L5 vertebra. Type-C – SIJ height is below the lowest point of the anterior cortex of the L5 vertebra. Type-D – a subgroup for those with a lumbosacral transitional vertebra, in particular a sacralised L5. Differences in transosseous corridor widths and lateral mass angles between classification types were assessed using two-way ANOVAs. Type-B was the most common pelvic type followed by Type-A, Type-C, and Type-D. Significant differences in the axial and coronal corridors was observed for all pelvic types at each level. Lateral mass angles increased from Types-A to C, but were smaller in Type-D. This classification system offers a guide to surgeons navigating variable pelvic anatomy and understanding how it is associated with the differences in transosseous sacral corridors. It can assist surgeons’ preoperative planning of screw position, choice of fixation or the need for technological assistance

A number of classification systems exist for posterior malleolus fractures of the ankle. The reliability of these classification systems remains unclear. The primary aim of this study was to evaluate the reliability of three commonly utilised fracture classification systems of the posterior malleolus. 60 patients across 2 hospitals sustaining an unstable ankle fracture with a posterior malleolus fragment were identified. All patients underwent radiographs and computed tomography of their injured ankle. 9 surgeons including pre-ST3 level, ST3-8 level, and consultant level applied the Haraguchi, Rammelt, and Mason & Molloy classifications to these patients, at two timepoints, at least 4 weeks apart. The order was randomised between assessments. Inter-rater reliability was assessed using Fleiss’ kappa and 95% confidence intervals (CI). Intra-rater reliability was assessed using Cohen's Kappa and standard error (SE). Inter-rater reliability (Fleiss’ Kappa) was calculated for the Haraguchi classification as 0.522 (95% CI 0.490 – 0.553), for the Rammelt classification as 0.626 (95% CI 0.600 – 0.652), and the Mason & Molloy classification as 0.541 (95% CI 0.514 – 0.569). Intra-rater reliability (Cohen's Kappa) was 0.764 (SE 0.034) for the Haraguchi, 0.763 (SE 0.031) for the Rammelt, 0.688 (SE 0.035) for the Mason & Molloy classification. This study reports the inter-rater and intra-rater reliability for three classification systems for posterior malleolus fractures. Based on definitions by Landis & Koch (1977), inter-rater reliability was rated as ‘moderate’ for the Haraguchi and Mason & Molloy classifications; and ‘substantial’ for the Rammelt classification. Similarly, the intra-rater reliability was rated as ‘substantial’ for all three classifications

Trochanteric femur fractures can be classified using the Jensen modification of the Evans’ classification or the AO/ASIF classification. This study compares the reproducibility of both classifications. Furthermore we evaluated the agreement on fracture stability, choice of osteosynthesis, fracture reduction and the accuracy of implant positioning. We used pre- and postoperative lateral and AP radiographs of 50 trochanteric femur fractures. The fractures were classified using both classifications with a three-month interval by five trauma surgeons and five residents. Inter-, and intra-observer variability was analysed using the multi-rater Fleiss’ kappa and the Cohen’ kappa tests. The AO/ASIF classification showed a kappa coefficient for the intra-observer agreement of 0.40 (SE 0.01). After leaving out classification-subgroups, AO/ASIF classification showed a coefficient of 0.68 (SE 0.02) and the Jensen classification a coefficient of 0.48 (SE 0.02). The kappa values of the intra-observer reliability of the AO/ASIF classification with and without subgroups were: 0.43 (SE 0.08) and 0.71 (SE 0.08) respectively. For the Jensen classification the kappa value was 0.56 (SE 0.09). Preoperative agreement on fracture stability and type of implant to be chosen showed kappa values of 0.39 (SE 0.05) and 0.65 (SE 0.04). Postoperative disagreement on the choice of implant was 15% (kappa 0.17, SE 0.08). Kappa values for postoperative fracture reduction and position of the implant were 0.29 (SE 0.09) and 0.22 (SE 0.05), respectively. Both the Jensen classification and the AO/ASIF classification showed poor reproducibility. However, without subgroups the AO/ASIF classification seemed more reliable. This study suggests that the definition of stability of trochanteric fractures remains controversial, which possibly complicates the choice of osteosynthesis. Refinement of the classifications or renewed definition of trochanteric fractures seems to be required

Complications are an inevitable part of orthopaedic surgery, how one defines complications can have an impact on the ability to learn from them. A group of general surgeons headed by Clavien and Dindo et al.1 have previously published their classification system for surgical complications based on the type of therapy required to correct the complication. Our aim was to evaluate a modification of this classification system and its use over a 12-month period at our institution via our departmental audits, our hypothesis being that this would direct appropriate discussion around our complications and hence learning and institutional change. A modified Clavien-Dindo Classification was prospectively applied to all complications recorded in the Orthopaedic departmental quarterly audits at our institution for a 12-month period (4 audits). The audit discussion was recorded and analysed and compared with the quarterly complication audits for the preceding 12-month period. The modified Clavien-Dindo classification for surgical complications was applicable and reproducible to Orthopaedic complications in our level 1 trauma centre. It is a transparent system, objective in its interpretation and avoids the tendency to down-grade serious complications. It was easy to apply and directed discussion appropriately at our quarterly audit meetings on complications where there was a preventable outcome or important learning point. In particular modifications to VTE and Death classes allowed the unit to focus discussion on cases where complication was preventable or unexpected. The modified Clavien-Dindo classification system is an easy to use and reproducible classification system for Orthopaedic complications in our unit it directed audit discussion towards cases where complications were preventable or had a learning point

Thoracolumbar injury classification systems are not used or researched extensively in paediatric population yet. This systematic review aims to explore the validity and reliability of the two main thoracolumbar injury classification systems in the paediatric population (age ≤ 18). It also aims to explore the transferability of adult classification systems to paediatrics. The Thoracolumbar Injury Classification System (TLICS) published in 2005 and the AO Spine published in 2013 were assessed in this paper because they both provide guidance for the assessment of the severity of an injury and recommend management strategies. A literature search was conducted on the following databases: Medline, EMBASE, Ovid during the period November 2020 to December 2020 for studies looking at the reliability and validity of the TLICS and AO Spine classification systems in paediatric population. Data on validity (to what extent TLICS/ AO Spine recommended treatment matched the actual treatment) and reliability (inter-rater and intra-rater reliability) was extracted. There is an “almost perfect validity” for TLICS. There is a “strong association” between the validity of TLICS and AO Spine. The intra-rater reliability is “moderate” for TLICS and “substantial” for AO Spine. The intra-rater reliability is “substantial” for TLICS and “almost perfect” for AO Spine. The six studies show a good overall validity and reliability for the application of TLICS and AO Spine in pediatric thoracolumbar fractures. However, implication of treatment and anatomical differences of the growing spine should be explored in detail. Therefore, AO Spine can be used in absence of any other classification system for paediatrics

Abstract. Introduction. Knee dislocations (KDs) are complex injuries which are often associated with damage to surrounding soft tissues or neurovascular structures. A classification system for these injuries should be simple and reproducible and allow communication among surgeons for surgical planning and outcome prediction. The aim of this study was to formulate a list of factors, prioritised by high-volume knee surgeons, that should be included in a KD classification system. Methods. A global panel of orthopaedic knee surgery specialists participated in a Delphi process. A list of factors to be included in a KD classification system was formulated by 91 orthopaedic surgeons, which was subsequently prioritised by 27 experts from 6 countries. The items were analysed to find factors that had at least 70% consensus for inclusion in a classification system. Results. The four factors that reached consensus agreement and thus deemed critical for inclusion in a classification system were vascular injuries (89%), common peroneal nerve injuries (78%), number of torn ligaments (78%), and open injuries (70%). Conclusion. The wide geographic distribution of participants provides diverse insight and makes the results of the study globally applicable. The most important factors to include in a classification system as determined by the Delphi technique were vascular injuries, common peroneal nerve injuries, number of torn ligaments, and open injuries. The Schenck anatomic classification system most accurately identifies these patient variables with the addition of open injuries. The authors propose to update the Schenck classification system with the inclusion of open injuries as an additional modifier

Aims. The Oswestry-Bristol Classification (OBC) was recently described as an MRI-based classification tool for the femoral trochlear. The authors demonstrated better inter- and intraobserver agreement compared to the Dejour classification. As the OBC could potentially provide a very useful MRI-based grading system for trochlear dysplasia, it was the aim to determine the inter- and intraobserver reliability of the classification system from the perspective of the non-founder. Methods. Two orthopaedic surgeons independently assessed 50 MRI scans for trochlear dysplasia and classified each according to the OBC. Both observers repeated the assessments after six weeks. The inter- and intraobserver agreement was determined using Cohen’s kappa statistic and S-statistic nominal and linear weights. Results. The OBC with grading into four different trochlear forms showed excellent inter- and intraobserver agreement with a mean kappa of 0.78. Conclusion. The OBC is a simple MRI-based classification system with high inter- and intraobserver reliability. It could present a useful tool for grading the severity of trochlear dysplasia in daily practice. Cite this article: Bone Joint Open 2020;1-7:355–358

Aim. To compare outcomes of PJI in relation to treatment method versus classification using the JS-BACH system. Method. Patients having surgery for EBJIS Criteria Confirmed PJI between 2010–2015 were included. Index surgical procedures were 1-stage or 2-stage revision or debridement and implant retention (DAIR). Patients completed the EuroQol EQ-5D-3L questionnaire and were followed clinically to a median of 4.7 years (IQR 2.7–6.7 years). Patients were stratified using the JS-BACH classification1 into either ‘Uncomplicated’, ‘Complex’ or having ‘Limited treatment options’, by two separate classifiers, blinded to clinical outcome. Results. 216 patients met the inclusion criteria. There were 51 patients classified as Uncomplicated (23.6%), 127 (58.8%) as Complex and 38 (17.6%) having Limited treatment options. Patients underwent either DAIR (n=97), 1-stage (n=35) or 2-stage (n=84) revision. Patients classified as Uncomplicated PJI had the lowest risk of recurrence or treatment failure, regardless of index procedure performed. Complex patients were significantly more likely than Uncomplicated patients to have recurrence following 2-stage revision (Odds Ratio 1.85; p=0.040) or DAIR (OR 1.83; p=0.037), but not 1-stage revision (OR 0.518; p=0.675). Limited treatment option patients had the highest recurrence risk regardless of index procedure (1-stage: OR 2.5 p=0.036; 2-stage: OR 3.3 p=0.004; DAIR: OR 3.40 p=0.006). At one year after surgery, Uncomplicated patients had the highest EQ-index scores (a marker of Quality of Life), with all treatments (EQ-5D-3L mean index scores; Uncomp 0.773, Complex 0.512, Limited Options 0.310: p<0.01). Differences in patient-reported outcomes were greater between the JS-BACH classification groups than between any methods of treatment. Conclusions. The JS-BACH classification effectively predicted outcome after three common PJI treatments. Comparing outcomes between treatments, without stratification of the patients, may be misleading as factors other than treatment method have a major effect on outcome. Classification may allow better allocation of individual treatments to provide optimal outcome for patients

In 2021, Vigdorchik et al. published a large multicentre study validating their simple Hip-Spine Classification for determining patient-specific acetabular component positioning in total hip arthroplasty (THA). The purpose of our study was to apply this Hip-Spine Classification to a sample of Australian patients undergoing THA surgery to determine the local acetabular component positioning requirements. Additionally, we propose a modified algorithm for adjusting cup anteversion requirements. 790 patients who underwent THA surgery between January 2021 and June 2022 were assessed for anterior pelvic plane tilt (APPt) and sacral slope (SS) in standing and relaxed seated positions and categorized according to their spinal stiffness and flatback deformity. Spinal stiffness was measured using pelvic mobility (PM); the ΔSS between standing and relaxed seated. Flatback deformity was defined by APPt <-13° in standing. As in Vigdorchik et al., PM of <10° was considered a stiff spine. For our algorithm, PM of <20° indicated the need for increased cup anteversion. Using this approach, patient-specific cup anteversion is increased by 1° for every degree the patient's PM is <20°. According to the Vigdorchik simple Hip-Spine classification groups, we found: 73% Group 1A, 19% Group 1B, 5% Group 2A, and 3% Group 2B. Therefore, under this classification, 27% of Australian THA patients would have an elevated risk of dislocation due to spinal deformity and/or stiffness. Under our modified definition, 52% patients would require increased cup anteversion to address spinal stiffness. The Hip-Spine Classification is a simple algorithm that has been shown to indicate to surgeons when adjustments to acetabular cup anteversion are required to account for spinal stiffness or flatback deformity. We investigated this algorithm in an Australian population of patients undergoing THA and propose a modified approach: increasing cup anteversion by 1° for every degree the patient's PM is <20°

Aims. A comprehensive classification for coronal lower limb alignment with predictive capabilities for knee balance would be beneficial in total knee arthroplasty (TKA). This paper describes the Coronal Plane Alignment of the Knee (CPAK) classification and examines its utility in preoperative soft tissue balance prediction, comparing kinematic alignment (KA) to mechanical alignment (MA). Methods. A radiological analysis of 500 healthy and 500 osteoarthritic (OA) knees was used to assess the applicability of the CPAK classification. CPAK comprises nine phenotypes based on the arithmetic HKA (aHKA) that estimates constitutional limb alignment and joint line obliquity (JLO). Intraoperative balance was compared within each phenotype in a cohort of 138 computer-assisted TKAs randomized to KA or MA. Primary outcomes included descriptive analyses of healthy and OA groups per CPAK type, and comparison of balance at 10° of flexion within each type. Secondary outcomes assessed balance at 45° and 90° and bone recuts required to achieve final knee balance within each CPAK type. Results. There was similar frequency distribution between healthy and arthritic groups across all CPAK types. The most common categories were Type II (39.2% healthy vs 32.2% OA), Type I (26.4% healthy vs 19.4% OA) and Type V (15.4% healthy vs 14.6% OA). CPAK Types VII, VIII, and IX were rare in both populations. Across all CPAK types, a greater proportion of KA TKAs achieved optimal balance compared to MA. This effect was largest, and statistically significant, in CPAK Types I (100% KA vs 15% MA; p < 0.001), Type II (78% KA vs 46% MA; p = 0.018). and Type IV (89% KA vs 0% MA; p < 0.001). Conclusion. CPAK is a pragmatic, comprehensive classification for coronal knee alignment, based on constitutional alignment and JLO, that can be used in healthy and arthritic knees. CPAK identifies which knee phenotypes may benefit most from KA when optimization of soft tissue balance is prioritized. Further, it will allow for consistency of reporting in future studies. Cite this article: Bone Joint J 2021;103-B(2):329–337

Objective. The aim of the study was to evaluate inter observer reliability and intra observer reproducibility between the three column classification using 3D CT reconstruction models and schatzker classification systems using 2D CT models. Materials and methods. Fifty two consecutive patients with tibial plateau fractures were evaluated by two orthopaedic surgeons. All patients were classified into Schatzker and three column classification systems using CTimages. The Images were evaluated in a randomised and blind fashion. Demographics of the patient were blinded to reduce observer bias. The inter observer reliability was measured for both classfications in round one. In round two the process was repeated after two weeks and the intra observer reproducibility was measured using cohen kappa coefficient and level of agreement based on Landis and Koch. Results. The average inter observer reliability for schatzker classification in round one were (k2D=0.661, 95% CI 0.531–0.697) in round two (k2D = 0.673, 95% CI 0.451–0.774). The three column classification average in round one were (k3D=0.851 95% CI 0.705–0.968), in round two (k3D=0.929 95% CI 0.813–1.00). The average intra observer reproducibility for Schatzker classification in round two for the first obsrever were (k2D=0.689 IQR, 0.6–0.846) for observer two (k2D=0.656 IQR 0.2988–1.0). The average intra observer reproducibility for three column for observer one were (k3D=0.693 IQR, 0.484-.859), for observer two (k3D=0.711 IQR, 0.5185–0.8294). 31 % of patients had a posterior column involvement. Conclusion. Statistically significant inter observer values in both rounds were noted with the three column classification making it, statistically an excellent agreement. The intra observer reproducibility for the three column classification improved as compared to the schatzker classification. The three column classification seems to be effective way to characterise and classify fractures of tibial plateau

Aims. To investigate if preoperative CT improves detection of unstable trochanteric hip fractures. Methods. A single-centre prospective study was conducted. Patients aged 65 years or older with trochanteric hip fractures admitted to Stavanger University Hospital (Stavanger, Norway) were consecutively included from September 2020 to January 2022. Radiographs and CT images of the fractures were obtained, and surgeons made individual assessments of the fractures based on these. The assessment was conducted according to a systematic protocol including three classification systems (AO/Orthopaedic Trauma Association (OTA), Evans Jensen (EVJ), and Nakano) and questions addressing specific fracture patterns. An expert group provided a gold-standard assessment based on the CT images. Sensitivities and specificities of surgeons’ assessments were estimated and compared in regression models with correlations for the same patients. Intra- and inter-rater reliability were presented as Cohen’s kappa and Gwet’s agreement coefficient (AC1). Results. We included 120 fractures in 119 patients. Compared to radiographs, CT increased the sensitivity of detecting unstable trochanteric fractures from 63% to 70% (p = 0.028) and from 70% to 76% (p = 0.004) using AO/OTA and EVJ, respectively. Compared to radiographs alone, CT increased the sensitivity of detecting a large posterolateral trochanter major fragment or a comminuted trochanter major fragment from 63% to 76% (p = 0.002) and from 38% to 55% (p < 0.001), respectively. CT improved intra-rater reliability for stability assessment using EVJ (AC1 0.68 to 0.78; p = 0.049) and for detecting a large posterolateral trochanter major fragment (AC1 0.42 to 0.57; p = 0.031). Conclusion. A preoperative CT of trochanteric fractures increased detection of unstable fractures using the AO/OTA and EVJ classification systems. Compared to radiographs, CT improved intra-rater reliability when assessing fracture stability and detecting large posterolateral trochanter major fragments. Cite this article: Bone Jt Open 2024;5(6):524–531

The Unified Classification System (UCS), or Vancouver system, is a validated and widely used classification system to guide the management of periprosthetic femoral fractures. It suggests that well-fixed stems (type B1) can be treated with fixation but that loose stems (types B2 and B3) should be revised. Determining whether a stem is loose can be difficult and some authors have questioned how to apply this classification system to polished taper slip stems which are, by definition, loose within their cement mantle. Recent evidence has challenged the common perception that revision surgery is preferable to fixation surgery for UCS-B periprosthetic fractures around cemented polished taper slip stems. Indications for fixation include an anatomically reducible fracture and cement mantle, a well-fixed femoral bone-cement interface, and a well-functioning acetabular component. However, not all type B fractures can or should be managed with fixation due to the risk of early failure. This annotation details specific fracture patterns that should not be managed with fixation alone. Cite this article: Bone Joint J 2023;105-B(5):481–486

Aims. The aim of this study was to assess the prognostic value of the modified three-group Stulberg classification, which is based on the sphericity of the femoral head, in patients with Perthes’ disease. Methods. A total of 88 patients were followed from the time of diagnosis until a mean follow-up of 21 years. Anteroposterior pelvic and frog-leg lateral radiographs were obtained at diagnosis and at follow-up of one, five, and 21 years. At the five- and 21-year follow-up, the femoral heads were classified using a modified three-group Stulberg classification (round, ovoid, or flat femoral head). Further radiological endpoints at long-term follow-up were osteoarthritis (OA) of the hip and the requirement for total hip arthroplasty (THA). Results. There were 71 males (81%) and 17 females. A total of 13 patients had bilateral Perthes’ disease; thus 101 hips were analyzed. At five-year follow-up, 37 hips were round, 38 ovoid, and 26 flat. At that time, 66 hips (65%) were healed and 91 (90%) were skeletally immature. At long-term follow-up, when the mean age of the patients was 28 years (24 to 34), 20 hips had an unsatisfactory outcome (seven had OA and 13 had required THA). There was a strongly significant association between the modified Stulberg classification applied atfive-year follow-up and an unsatisfactory outcome at long-term follow-up (p < 0.001). Between the five- and 21-year follow-up, 67 hips (76%) stayed in their respective modified Stulberg group, indicating a strongly significant association between the Stulberg classifications at these follow-ups (p < 0.001). Conclusion. The modified Stulberg classification is a strong predictor of long-term radiological outcome in patients with Perthes’ disease. It can be applied at the healing stage, which is usually reached five years after the diagnosis is made and before skeletal maturity. Cite this article: Bone Joint J 2021;103-B(12):1815–1820

Aims. Patients with spinal pathology who undergo total hip arthroplasty (THA) have an increased risk of dislocation and revision. The aim of this study was to determine if the use of the Hip-Spine Classification system in these patients would result in a decreased rate of postoperative dislocation in patients with spinal pathology. Methods. This prospective, multicentre study evaluated 3,777 consecutive patients undergoing THA by three surgeons, between January 2014 and December 2019. They were categorized using The Hip-Spine Classification system: group 1 with normal spinal alignment; group 2 with a flatback deformity, group 2A with normal spinal mobility, and group 2B with a stiff spine. Flatback deformity was defined by a pelvic incidence minus lumbar lordosis of > 10°, and spinal stiffness was defined by < 10° change in sacral slope from standing to seated. Each category determined a patient-specific component positioning. Survivorship free of dislocation was recorded and spinopelvic measurements were compared for reliability using intraclass correlation coefficient. Results. A total of 2,081 patients met the inclusion criteria. There were 987 group 1A, 232 group 1B, 715 group 2A, and 147 group 2B patients. A total of 70 patients had a lumbar fusion, most had L4-5 (16; 23%) or L4-S1 (12; 17%) fusions; 51 patients (73%) had one or two levels fused, and 19 (27%) had > three levels fused. Dual mobility (DM) components were used in 166 patients (8%), including all of those in group 2B and with > three level fusions. Survivorship free of dislocation at five years was 99.2% with a 0.8% dislocation rate. The correlation coefficient was 0.83 (95% confidence interval 0.89 to 0.91). Conclusion. This is the largest series in the literature evaluating the relationship between hip-spine pathology and dislocation after THA, and guiding appropriate treatment. The Hip-Spine Classification system allows surgeons to make appropriate evaluations preoperatively, and it guides the use of DM components in patients with spinopelvic pathology in order to reduce the risk of dislocation in these high-risk patients. Cite this article: Bone Joint J 2021;103-B(7 Supple B):17–24

Aims. Iliosacral sarcoma resections have been shown to have high rates of local recurrence (LR) and poor overall survival. There is also no universal classification for the resection of pelvic sarcomas invading the sacrum. This study proposes a novel classification system and analyzes the survival and risk of recurrence, when using this system. Methods. This is a retrospective analysis of 151 patients (with median follow-up in survivors of 44 months (interquartile range 12 to 77)) who underwent hemipelvectomy with iliosacral resection at a single centre between 2007 and 2019. The proposed classification differentiates the extent of iliosacral resection and defines types S1 to S6 (S1 resection medial and parallel to the sacroiliac joint, S2 resection through the ipsilateral sacral lateral mass to the neuroforamina, S3 resection through the ipsilateral neuroforamina, S4 resection through ipsilateral the spinal canal, and S5 and S6 contralateral sacral resections). Descriptive statistics and the chi-squared test were used for categorical variables, and the Kaplan-Meier survival analysis were performed. Results. Resections were S1 in 25/151 patients (17%), S2 in 70/151 (46%), S3 in 33/151 (22%), S4 in 77/151 (11%), S5 in 4/151 (3%), and S6 in 2/151 (1%). An internal hemipelvectomy was performed in 113/151 patients (75%), and 38/151 patients (25%) had an external hemipelvectomy. The predominant types of sarcoma were high-grade osteosarcoma in 48/151 patients (32%), chondrosarcoma in 41/151 (27%), Ewing sarcoma in 33/151 (22%), pleomorphic sarcoma in 17/151 (11%), and others in 2/151 (8%). LR was found in 24/151 patients (15%) with S3, S5, with S6 resections showing the highest rate of LR (p = 0.038). Overall, 19/151 patients (16%) had evidence of metastastic disease at the time of surgery and these patients showed poorer survival when compared to patients with no metastasis. Conclusion. The proposed classification can help to report and compare different surgical and reconstructive approaches in these difficult cases who are still have a considerable risk of LR. Cite this article: Bone Joint J 2022;104-B(2):290–296

Aims. The Wrightington classification system of fracture-dislocations of the elbow divides these injuries into six subtypes depending on the involvement of the coronoid and the radial head. The aim of this study was to assess the reliability and reproducibility of this classification system. Methods. This was a blinded study using radiographs and CT scans of 48 consecutive patients managed according to the Wrightington classification system between 2010 and 2018. Four trauma and orthopaedic consultants, two post CCT fellows, and one speciality registrar based in the UK classified the injuries. The seven observers reviewed preoperative radiographs and CT scans twice, with a minimum four-week interval. Radiographs and CT scans were reviewed separately. Inter- and intraobserver reliability were calculated using Fleiss and Cohen kappa coefficients. The Landis and Koch criteria were used to interpret the strength of the kappa values. Validity was assessed by calculating the percentage agreement against intraoperative findings. Results. Of the 48 patients, three (6%) had type A injury, 11 (23%) type B, 16 (33%) type B+, 16 (33%) Type C, two (4%) type D+, and none had a type D injury. All 48 patients had anteroposterior (AP) and lateral radiographs, 44 had 2D CT scans, and 39 had 3D reconstructions. The interobserver reliability kappa value was 0.52 for radiographs, 0.71 for 2D CT scans, and 0.73 for a combination of 2D and 3D reconstruction CT scans. The median intraobserver reliability was 0.75 (interquartile range (IQR) 0.62 to 0.79) for radiographs, 0.77 (IQR 0.73 to 0.94) for 2D CT scans, and 0.89 (IQR 0.77 to 0.93) for the combination of 2D and 3D reconstruction. Validity analysis showed that accuracy significantly improved when using CT scans (p = 0.018 and p = 0.028 respectively). Conclusion. The Wrightington classification system is a reliable and valid method of classifying fracture-dislocations of the elbow. CT scans are significantly more accurate than radiographs when identifying the pattern of injury, with good intra- and interobserver reproducibility. Cite this article: Bone Joint J 2020;102-B(8):1041–1047

There is good scientific rationale to support the use of growth factors to promote musculoskeletal tissue regeneration. However, the clinical effectiveness of platelet-rich plasma (PRP) and other blood-derived products has yet to be proven. Characterization and reporting of PRP preparation protocols utilized in clinical trials for the treatment of musculoskeletal disease is highly inconsistent, and the majority of studies do not provide sufficient information to allow the protocols to be reproduced. Furthermore, the reporting of blood-derived products in orthopaedics is limited by the multiple PRP classification systems available, which makes comparison of results between studies challenging. Several attempts have been made to characterize and classify PRP; however, no consensus has been reached, and there is lack of a comprehensive and validated classification. In this annotation, we outline existing systems used to classify preparations of PRP, highlighting their advantages and limitations. There remains a need for standardized universal nomenclature to describe biological therapies, as well as a comprehensive and reproducible classification system for autologous blood-derived products. Cite this article: Bone Joint J 2019;101-B:891–896

Objectives. Using a simple classification method, we aimed to estimate the collapse rate due to osteonecrosis of the femoral head (ONFH) in order to develop treatment guidelines for joint-preserving surgeries. Methods. We retrospectively analyzed 505 hips from 310 patients (141 men, 169 women; mean age 45.5 years . (sd. 14.9; 15 to 86)) diagnosed with ONFH and classified them using the Japanese Investigation Committee (JIC) classification. The JIC system includes four visualized types based on the location and size of osteonecrotic lesions on weightbearing surfaces (types A, B, C1, and C2) and the stage of ONFH. The collapse rate due to ONFH was calculated using Kaplan–Meier survival analysis, with radiological collapse/arthroplasty as endpoints. Results. Bilateral cases accounted for 390 hips, while unilateral cases accounted for 115. According to the JIC types, 21 hips were type A, 34 were type B, 173 were type C1, and 277 were type C2. At initial diagnosis, 238/505 hips (47.0%) had already collapsed. Further, the cumulative survival rate was analyzed in 212 precollapsed hips, and the two-year and five-year collapse rates were found to be 0% and 0%, 7.9% and 7.9%, 23.2% and 36.6%, and 57.8% and 84.8% for types A, B, C1, and C2, respectively. Conclusion. Type A ONFH needs no further treatment, but precollapse type C2 ONFH warrants immediate treatment with joint-preserving surgery. Considering the high collapse rate, our study results justify the importance of early diagnosis and intervention in asymptomatic patients with type C2 ONFH. Cite this article: Y. Kuroda, T. Tanaka, T. Miyagawa, T. Kawai, K. Goto, S. Tanaka, S. Matsuda, H. Akiyama. Classification of osteonecrosis of the femoral head: Who should have surgery?. Bone Joint Res 2019;8:451–458. DOI: 10.1302/2046-3758.810.BJR-2019-0022.R1

This study aims to implement and assess the inter and intra-reliability of a modernised radiolucency assessment system; the Radiolucency In cemented Stemmed Knee (RISK) arthroplasty classification. Furthermore, we assessed the distribution of regions affected by radiolucency in patients undergoing stemmed cemented knee arthroplasty. Stemmed knee arthroplasty cases over 7-year period at a single institution were retrospectively identified and reviewed. The RISK classification system identifies five zones in the femur and five zones in the tibia in both the anteroposterior (AP) and lateral planes. Post-operative and follow-up radiographs were scored for radiolucency by four blinded reviewers at two distinct time points four weeks apart. Reliability was assessed using the kappa statistic. A heat map was generated to demonstrate the reported regions of radiolucency. 29 cases (63 radiographs) of stemmed knee arthroplasty were examined radiographically using the RISK system. Intra-reliability (0.83) and Inter-reliability (0.80) scores were both consistent with a strong level of agreement using the kappa scoring system. Radiolucency was more commonly associated with the tibial component (76.6%) compared to the femoral component (23.3%), and the tibial anterior-posterior (AP) region 1 (medial plateau) was the most affected (14.9%). The RISK classification system is a reliable assessment tool for evaluating radiolucency around stemmed knee arthroplasty using defined zones on both AP and lateral radiographs. Zones of radiolucency identified in this study may be relevant to implant survival and corresponded well with zones of fixation, which may help inform future research

Muller-Weiss disease is an uncommon condition with unclear etiology and no gold standard treatment. The question arises; which joints to fuse? Although no consensuses prevail, one must postulate fusion should include those affected. Consequently, to establish an algorithm for its surgical management we set out to study clinical and radiographic features with use of SPECT-CT and a literature review. 57 consecutive feet presenting with Muller-Weiss disease analysed; 15 men, 25 women, age 22–84. Condition bilateral in 17, left side 16, right in 7 patients. Specific history and examination by senior author. Radiographic series and SPECT-CT obtained with surgery performed on significantly symptomatic feet. Measurements of Meary-Tomeno angles, anteroposterior thickness of navicular at the midpoint of each naviculo-cuneiform, alongside the medial extrusion distance and percentage of compression in each case performed. Poor correlation between Meary's angle and 1) degree of compression at naviculo-cuneiform joints, 2) degree of extrusion 3) compression vs extrusion using R. 2. coefficient of determination (invalidating Maceira et al. classification). In unilateral cases, extrusion significantly greater on affected side 94.7% (P< 0.001 Fisher exact test). Degree of extrusion significantly greater in bilateral than unilateral cases (p=0.004 unpaired T test). Valgus hindfoot and Meary's negative most common pattern with no correlation between heel alignment and Meary's R. 2. = 0.003. SPECT-CT useful to determine subtalar involvement in ‘stage 2 disease.’. Following review of cases and published literature we propose the following classification for Muller-Weiss disease with treatment algorithm. 3 Stage delineation; Stage 1 (Normal hindfoot alignment); 1A. Talonavicular disease only - Isolated Talonavicular arthrodesis 1B. Talonavicular + Subtalar; double medial or triple arthrodesis. Stage 2. Talonavicular + Naviculocuneiform; 2A. Adequate bone stock - Talo-naviculo-cuneiform arthrodesis, 2B. Inadequate bone stock +- subtalar disease; Talo-naviculo-cuneiform arthrodesis with tricortical bone graft (Mayich). Stage 3; Asymmetric ankle varus. Pantalar arthrodesis Double/triple/TNC/TAR arthrodesis with hindfoot re-alignment

Objectives. Open fracture classification systems are limited in their use. Our objective was to classify open tibia and femur fractures using the OTS classification system in a region with high incidence of gunshot fractures. One hundred and thirty-seven patients with diaphyseal tibia and femur open fractures were identified from a prospectively collected cohort of patients. This database contained all cases (closed and open fractures) of tibial and femoral intramedullary nailed patients older than 18 years old during the period of September 2017 to May 2021. Exclusion criteria included closed fractures, non-viable limbs, open fractures > 48 hours to first surgical debridement and patients unable to follow up over a period of 12 months (a total of 24). Open fractures captured and classified in the HOST study using the Gustilo-Anderson classification, were reviewed and reclassified using the OTS open fracture classification system, analysing gunshot fractures in particular. Ninety percent were males with a mean age of 34. Most common mechanism was civilian gunshot wounds (gsw) in 54.7% of cases. In 52.6% of cases soft tissue management was healing via secondary intention, these not encompassed in the classification. Fracture classification was OTS Simple in 23.4%, Complex B in 24.1% and 52.6% of cases unclassified. The OTS classification system was not comprehensive in the classification of open tibia and femur fractures in a setting of high incidence of gunshot fractures. An amendment has been proposed to alter acute management to appropriate wound care and to subcategorise Simple into A and B subdivisions; no soft tissue intervention and primary closure respectively. This will render the OTS classification system more inclusive to all open fractures of all causes with the potential to better guide patient care and clinical research

Aims. Tibial plateau fractures (TPFs) are complex injuries around the knee caused by high- or low-energy trauma. In the present study, we aimed to define the distribution and frequency of TPF lines using a 3D mapping technique and analyze the rationalization of divisions employed by frequently used classifications. Methods. In total, 759 adult patients with 766 affected knees were retrospectively reviewed. The TPF fragments on CT were multiplanar reconstructed, and virtually reduced to match a 3D model of the proximal tibia. 3D heat mapping was subsequently created by graphically superimposing all fracture lines onto a tibia template. Results. The cohort included 405 (53.4%) cases with left knee injuries, 347 (45.7%) cases with right knee injuries, and seven (0.9%) cases with bilateral injuries. On mapping, the hot zones of the fracture lines were mainly concentrated around the anterior cruciate ligament insertion, posterior cruciate ligament insertion, and the inner part of the lateral condyle that extended to the junctional zone between Gerdy’s tubercle and the tibial tubercle. Moreover, the cold zones were scattered in the posteromedial fragment, superior tibiofibular syndesmosis, Gerdy’s tubercle, and tibial tubercle. TPFs with different Orthopaedic Trauma Association/AO Foundation (OTA/AO) subtypes showed peculiar characteristics. Conclusion. TPFs occurred more frequently in the lateral and intermedial column than in the medial column. Fracture lines of tibial plateau occur frequently in the transition zone with marked changes in cortical thickness. According to 3D mapping, the four-column and nine-segment classification had a high degree of matching as compared to the frequently used classifications. Cite this article: Bone Joint Res 2020;9(6):258–267

Aim. This study assesses the ability of the JS-BACH classification of bone infection to predict clinical and patient-reported outcomes in prosthetic joint infection (PJI). Method. Patients who received surgery for suspected PJI at two specialist bone infection centres within the UK between 2010 and 2015 were classified using the JS-BACH classification into either ‘uncomplicated’, ‘complex’ or ‘limited options’. All patients were classified by two clinicians blinded to outcome, with any discrepancies adjudicated by a third reviewer. At the most recent follow-up, patients were assessed for (i) any episode of recurrence since the index operation and (ii) the status of the joint. A Cox proportional-hazard model assessed significant predictors of recurrence following the index procedure. Patient-reported outcomes included the EuroQol EQ-5D-3L index score and the EQ-visual analogue score (VAS) at 0, 14, 42, 120 and 365 days following the index operation. Results. 220 patients met the inclusion criteria during the study period which included PJI of the knee (n=111), hip (n=102), shoulder (n=4) and elbow (n=3). The median time to final follow-up was 4.7 years (inter-quartile range 2.7 – 6.7 years). Controlling for type of index procedure and site of infection, Cox proportional-hazards ratio of recurrence when being classified as complex versus uncomplicated was 25.2 (95% CI 3.45 – 183.7, p<0.001) and having limited options verses uncomplicated was 59.0 (95% CI 7.93 – 439.1, p<0.001). None of the patients who were classified as ‘uncomplicated’ PJI (0/52) had received either amputation, joint fusion, excision arthroplasty, chronic suppressive anti-biotics, had died from sepsis secondary to PJI or were awaiting treatment for an active infection at final follow-up. This compared to 21.3% (27/127) of patients classified as ‘complex’ PJI and 65.9% (27/41) of patients classified as ‘limited options’. Compared to the age-matched population, patients with ‘uncomplicated’ PJI reported similar EQ-index scores (age-matched population: 0.782, ‘uncomplicated’: 0.730, SD 0.326) and EQ-VAS (age-matched: 77.9, ‘uncomplicated’ PJI: 79.4, SD 20.9). This was significantly higher when compared to patients classified as ‘complex’ (EQ-index: 0.515 SD 0.323, p<0.012; EQ-VAS: 68.4 SD 19.4, p=0.042) and ‘limited options’ (EQ-index: 0.333 SD 0.383, p<0.001; EQ-VAS: 60.2, SD 23.1, p=0.005, ANOVA with Tukey post-hoc comparison). Conclusions. We have demonstrated that the JS-BACH classification for bone and joint infection is a significant predictor of clinical outcome and quality of life following surgery for PJI. This will allow clinicians to offer prognostic information to patients and guide the timing of referral for specialist management in PJI

Introduction. The current treatment for Freiberg's osteochondrosis centres around either: simple debridement or debridement osteotomy. The main principle of the osteotomy is to rotate normal articular cartilage into the affected area. We recommend the use of CT scanning to delineate the amount of available, unaffected cartilage available to rotate into the affected space. Methods. We retrospectively reviewed 32 CT scans of new Freiberg's diagnoses in Sheffield over a 10 year period using the PACS system. We identified the sagittal CT slice that displayed the widest portion of proximal articular margin of the proximal phalanx and measured the diseased segment of the corresponding metatarsal head as an arc (in degrees). This arc segment was divided by 360°. This gave a ratio of the affected arc in the sagittal plane. Results. 28 out of 32 cases involved the 2nd metatarsal with the remaining 4 involving the 3rd metatarsal head. Of 32 cases, 18 had fragmentation. Surgically, 20 had debridement only, 5 also had an osteotomy and 1 had a fusion. 6 of the 32 cases were managed non-operatively. 11 cases out of 32 had an arc ratio of < 0.3. Of these, only 3 had an osteotomy, 3 had no procedure and 5 had a simple debridement. Of those that had osteotomies (5/32), 3 of the 5 cases had an arc ratio of < 0.3 with the other 2 being 0.42 and 0.38. Discussion. We hypothesise that those cases with an arc ratio of less 0.3 would be amenable to a dorsal closing wedge osteotomy and those with a ratio of more than 0.4 would be better suited to a simple debridement. For those cases between 0.3–0.4, we feel either option is viable. Further work to prove or disprove outcomes related to our classification is required

Aims. This study explores data quality in operation type and fracture classification recorded as part of a large research study and a national audit with an independent review. Patients and Methods. At 17 centres, an expert surgeon reviewed a randomly selected subset of cases from their centre with regard to fracture classification using the AO system and type of operation performed. Agreement for these variables was then compared with the data collected during conduct of the World Hip Trauma Evaluation (WHiTE) cohort study. Both types of surgery and fracture classification were collapsed to identify the level of detail of reporting that achieved meaningful agreement. In the National Hip Fracture Database (NHFD), the types of operation and fracture classification were explored to identify the proportion of “highly improbable” combinations. Results. The records were reviewed for 903 cases. Agreement for the subtypes of extracapsular fracture was poor; most centres achieved no better than “fair” agreement. When the classification was collapsed to a single option for “extracapsular” fracture, only four centres failed to have at least “moderate” agreement. There was only “moderate” agreement for the subtypes of intracapsular fracture, which improved to “substantial” when collapsed to “intracapsular”. Subtrochanteric fracture types were well reported with “substantial” agreement. There was near “perfect” agreement for internal fixation procedures. “Perfect” or “substantial” agreement was achieved when the type of arthroplasty surgery was reported at the level of “hemiarthroplasty” and “total hip replacement”. When reviewing data submitted to the NHFD, a minimum of 5.2% of cases contained “highly improbable” procedures for the stated fracture classification. Conclusion. The complexity of collecting fracture classification data at a national scale compromises the accuracy with which detailed classification systems can be reported. Data around type of surgery performed show similar tendencies. Data capture, reporting, and interpretation in future studies must take this into account. Cite this article: Bone Joint J 2019;101-B:1292–1299

Background. The cavovarus foot is a complex 3-dimensional deformity. Although a multitude of techniques are described for its surgical management, few of these are evidence based or guided by classification systems. Surgical management involves realignment of the hindfoot and soft tissue balancing, followed by forefoot balancing. Our aim was to classify the pattern of residual forefoot deformities once the hindfoot is corrected, to guide forefoot correction. Methods. We included 20 cavovarus feet from adult patients with Charcot-Marie-Tooth who underwent weightbearing CT (mean age 43.4 years, 14 males). Patients included had flexible deformities, with no previous surgery. Previous work established majority of rotational deformity in cavovarus feet occurs at the talonavicular joint, which is often reduced during surgery. Using specialised software (Bonelogic 2.1, Disior) a 3-dimensional, virtual model was created. Using data from normal feet as a guide, the talonavicular joint of the cavovarus feet was digitally reduced to a ‘normal’ position. Models of the corrected position were exported and geometrically analysed using Blender 3.6 to identify anatomical trends. Results. We identified 3 types of cavovarus forefoot morphotypes. Type 1 was seen in 13 cases (65%) and was defined as a foot where only the first metatarsal was relatively plantarflexed to the rest of the foot, with no significant residual adduction after talonavicular correction. Type 2 was seen in 4 cases (20%) and was defined as a foot where the second and first metatarsals were progressively plantarflexed, with no significant adduction. Type 3 was seen in 3 cases (15%) and was defined as a foot where the metatarsals were still adducted after talonavicular de-rotation. Conclusion. We classify 3 forefoot morphotypes in cavovarus feet. It is important to recognise and anticipate the residual forefoot deformities after hindfoot correction as different treatment strategies may be required for different morphotypes to achieve balanced correction

Aims. The number of convolutional neural networks (CNN) available for fracture detection and classification is rapidly increasing. External validation of a CNN on a temporally separate (separated by time) or geographically separate (separated by location) dataset is crucial to assess generalizability of the CNN before application to clinical practice in other institutions. We aimed to answer the following questions: are current CNNs for fracture recognition externally valid?; which methods are applied for external validation (EV)?; and, what are reported performances of the EV sets compared to the internal validation (IV) sets of these CNNs?. Methods. The PubMed and Embase databases were systematically searched from January 2010 to October 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The type of EV, characteristics of the external dataset, and diagnostic performance characteristics on the IV and EV datasets were collected and compared. Quality assessment was conducted using a seven-item checklist based on a modified Methodologic Index for NOn-Randomized Studies instrument (MINORS). Results. Out of 1,349 studies, 36 reported development of a CNN for fracture detection and/or classification. Of these, only four (11%) reported a form of EV. One study used temporal EV, one conducted both temporal and geographical EV, and two used geographical EV. When comparing the CNN’s performance on the IV set versus the EV set, the following were found: AUCs of 0.967 (IV) versus 0.975 (EV), 0.976 (IV) versus 0.985 to 0.992 (EV), 0.93 to 0.96 (IV) versus 0.80 to 0.89 (EV), and F1-scores of 0.856 to 0.863 (IV) versus 0.757 to 0.840 (EV). Conclusion. The number of externally validated CNNs in orthopaedic trauma for fracture recognition is still scarce. This greatly limits the potential for transfer of these CNNs from the developing institute to another hospital to achieve similar diagnostic performance. We recommend the use of geographical EV and statements such as the Consolidated Standards of Reporting Trials–Artificial Intelligence (CONSORT-AI), the Standard Protocol Items: Recommendations for Interventional Trials–Artificial Intelligence (SPIRIT-AI) and the Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis–Machine Learning (TRIPOD-ML) to critically appraise performance of CNNs and improve methodological rigor, quality of future models, and facilitate eventual implementation in clinical practice. Cite this article: Bone Jt Open 2021;2(10):879–885

The Gartland extension-type supracondylar humerus fracture is the most common elbow fracture in the paediatric population. Depending on fracture classification, treatment options range from nonoperative treatment such as taping, splinting or casting to operative treatments such as closed reduction and percutaneous pinning or open reduction. Classification variability between surgeons is a potential contributing factor to existing controversy over nonoperative versus operative treatment for Type II supracondylar fractures. The purpose of this study was to investigate levels of agreement in classification of extension-type supracondylar humerus fractures using the Gartland classification system. A retrospective chart review was conducted on patients aged 2–12 years who had sustained an extension-type supracondylar fracture and received either operative or nonoperative treatment at a tertiary children's hospital. De-identified baseline anteroposterior (AP) and lateral plain elbow radiographs were provided along with a brief summary of the modified Gartland classification system to surgeons across Canada, United States, Australia, United Kingdom and India. Each surgeon was blinded to patient treatment and asked to classify the fractures as Type I, IIA, IIB or III according to the classification system provided. A total of 21 paediatric orthopaedic surgeons completed one round of classification, of these, 15 completed a second round using the same radiographs in a reshuffled order. Kappa values using pre-determined weighted kappa coefficients were calculated to assess interobserver and intraobserver levels of agreement. In total, 60 sets of baseline elbow radiographs were provided to survey respondents. Interobserver agreement for classification based on the Gartland criteria between surgeons was a mean of 0.68, 95% CI [0.67, 0.69] (0.61–0.80 considered substantial agreement). Intraobserver agreement was a mean of 0.80 [0.75, 0.84]. (0.61–0.80 substantial agreement, 0.81–1 almost perfect agreement). Radiographic classification of extension-type supracondylar humerus fractures at baseline demonstrated substantial agreement both between and within surgeon raters. Levels of agreement are substantial enough to suggest that classification variability is not a major contributing factor to variability in treatment between surgeons for Type II supracondylar fractures. Further research is needed to compare patient outcomes between nonoperative and operative treatment for these fractures, so as to establish consensus and a standardized treatment protocol for optimal patient care across centres

Introduction and Objective. The Cartilage Oligomeric Matrix Protein (COMP) is a glycoprotein that is elevated in patients with osteoarthritis. The elevation increases linearly with the radiological grade of osteoarthritis. The objective of this study was to study the levels of COMP in knee osteoarthritis in the Indian population and to correlate (establish ranges) with the specific radiological grade of osteoarthritis (Kellgreen and Lawrence grading). Since the radiological classification is subjective, the COMP levels would serve as a more objective way of classifying osteoarthritic joints. Materials and Methods. We analysed the COMP levels by the Enzyme Linked Immunosorbent Assay (ELISA) method in 100 patients presenting to the outpatient clinic of our hospital, after obtaining due approvals. The radiographs of these patients were classified according to the Kellgreen-Lawrence grading by a senior orthopaedic surgeon. Results. We found a linear correlation with the COMP levels and the radiological classification as established in the previous studies. We were also able to establish a range of COMP levels for each classification stage. Conclusions. This study would provide means to classify osteoarthritis without the need for radiographs thus minimising radiation to the patient. It would also help us to predict the radiological findings thus serving as a guide for further treatment planning

Aims. Hip arthroscopy (HA) has become the treatment of choice for femoroacetabular impingement (FAI). However, less favourable outcomes following arthroscopic surgery are expected in patients with severe chondral lesions. The aim of this study was to assess the outcomes of HA in patients with FAI and associated chondral lesions, classified according to the Outerbridge system. Methods. A systematic search was performed on four databases. Studies which involved HA as the primary management of FAI and reported on chondral lesions as classified according to the Outerbridge classification were included. The study was registered on PROSPERO. Demographic data, patient-reported outcome measures (PROMs), complications, and rates of conversion to total hip arthroplasty (THA) were collected. Results. A total of 24 studies were included with a total of 3,198 patients (3,233 hips). Patients had significantly less improvement in PROMs if they had Outerbridge grade III and IV lesions (p = 0.012). Compared with microfracture, autologous matrix-induced chondrogenesis (AMIC) resulted in significantly reduced rates of conversion to THA (p = 0.042) and of revision arthroscopy (p = 0.038). Chondral repair procedures in these patients also did not significantly reduce the rates of conversion to THA (p = 0.931), or of revision arthroscopy (p = 0.218). However, compared with microfracture, AMIC significantly reduced the rates of conversion to THA (p = 0.001) and of revision arthroscopy (p = 0.011) in these patients. Those with Outerbridge grade III and IV lesions also had significantly increased rates of conversion to THA (p = 0.029) and of revision arthroscopy (p = 0.023) if they had associated lesions of the acetabulum and femoral head. Those who underwent labral debridement had a significantly increased rate of conversion to THA compared with those who underwent labral repair (p = 0.015). Conclusion. There is universal improvement in PROMs following HA in patients with FAI and associated chondral lesions. However, those with Outerbridge grade III and IV lesions had significantly less improvement in PROMs and a significantly increased rate of conversion to THA than those with Outerbridge grade I and II. This suggests that the outcome of HA in patients with FAI and severe articular cartilage damage may not be favourable. Cite this article: Bone Joint J 2023;105-B(7):751–759

INTRODUCTION. The Dorr Bone Classification, devised in 1993 is commonly used to categorize bone types prior to hip reconstruction. The purpose of the present study is to quantify the Dorr classification system using 4 morphologic parameters – morphologic cortical index (MCI), canal-flare index (CFI), canal-bone ratio (CBR), and canal-calcar ratio (CCR). METHODS. 816 hips were reviewed. Demographic data reviewed includes age, sex, and laterality. Each hip was reviewed by 2 separate evaluators for Dorr classification. The MCI, CCR, CBR, and CFI were calculated for each hip on anteroposterior radiographs (Fig 1). One-way ANOVA statistical analysis was used to examine if there are mean differences for each measurement. IRB approval was obtained before collection of data. RESULTS. The average age of patients was 61 (range 20–96). There were 367 left hips and 449 right hips. The prevalence of Dorr A was 45.8%. The prevalence of Dorr B bone was 38.9% and of Dorr C bone was 15.3%. One-way ANOVA analysis confirmed the mean differences for each measurement. Measurements of the MCI, CCR, CBR, and CFI were statistically significantly different between the three types of bone. The MCI and CFI were significantly higher in Type A than Type B and higher in Type B than Type C. The CBR and CCR were significantly lower in Type A than Type B and lower in Type B than Type C. DISCUSSION. To our knowledge, the present study is the first to attempt to quantify the Dorr Bone classification system using MCI, CCR, CBR, and CFI using a large series of patients. Classification of the proximal femur geometry is important as it may play a role in implant fixation for patients undergoing total hip arthroplasty (THA). Furthermore, this information can be used to guide future implant choices

Aims. Besides conventional radiographs, the use of MRI, CT, and bone scintigraphy is frequent in the diagnosis of a fracture of the scaphoid. However, which techniques give the best results remain unknown. The investigation of a new imaging technique initially requires an analysis of its precision. The primary aim of this study was to investigate the interobserver agreement of high-resolution peripheral quantitative CT (HR-pQCT) in the diagnosis of a scaphoid fracture. A secondary aim was to investigate the interobserver agreement for the presence of other fractures and for the classification of scaphoid fracture. Methods. Two radiologists and two orthopaedic trauma surgeons evaluated HR-pQCT scans of 31 patients with a clinically-suspected scaphoid fracture. The observers were asked to determine the presence of a scaphoid or other fracture and to classify the scaphoid fracture based on the Herbert classification system. Fleiss kappa statistics were used to calculate the interobserver agreement for the diagnosis of a fracture. Intraclass correlation coefficients (ICCs) were used to assess the agreement for the classification of scaphoid fracture. Results. A total of nine (29%) scaphoid fractures and 12 (39%) other fractures were diagnosed in 20 patients (65%) using HR-pQCT across the four observers. The interobserver agreement was 91% for the identification of a scaphoid fracture (95% confidence interval (CI) 0.76 to 1.00) and 80% for other fractures (95% CI 0.72 to 0.87). The mean ICC for the classification of a scaphoid fracture in the seven patients diagnosed with scaphoid fracture by all four observers was 73% (95% CI 0.42 to 0.94). Conclusion. We conclude that the diagnosis of scaphoid and other fractures is reliable when using HR-pQCT in patients with a clinically-suspected fracture. Cite this article: Bone Joint J 2020;102-B(4):478–484

Aims. This aim of this study was to assess the reliability and validity of the Unified Classification System (UCS) for postoperative periprosthetic femoral fractures (PFFs) around cemented polished taper-slip (PTS) stems. Methods. Radiographs of 71 patients with a PFF admitted consecutively at two centres between 25 February 2012 and 19 May 2020 were collated by an independent investigator. Six observers (three hip consultants and three trainees) were familiarized with the UCS. Each PFF was classified on two separate occasions, with a mean time between assessments of 22.7 days (16 to 29). Interobserver reliability for more than two observers was assessed using percentage agreement and Fleiss’ kappa statistic. Intraobserver reliability between two observers was calculated with Cohen kappa statistic. Validity was tested on surgically managed UCS type B PFFs where stem stability was documented in operation notes (n = 50). Validity was assessed using percentage agreement and Cohen kappa statistic between radiological assessment and intraoperative findings. Kappa statistics were interpreted using Landis and Koch criteria. All six observers were blinded to operation notes and postoperative radiographs. Results. Interobserver reliability percentage agreement was 58.5% and the overall kappa value was 0.442 (moderate agreement). Lowest kappa values were seen for type B fractures (0.095 to 0.360). The mean intraobserver reliability kappa value was 0.672 (0.447 to 0.867), indicating substantial agreement. Validity percentage agreement was 65.7% and the mean kappa value was 0.300 (0.160 to 0.4400) indicating only fair agreement. Conclusion. This study demonstrates that the UCS is unsatisfactory for the classification of PFFs around PTS stems, and that it has considerably lower reliability and validity than previously described for other stem types. Radiological PTS stem loosening in the presence of PFF is poorly defined and formal intraoperative testing of stem stability is recommended. Cite this article: Bone Joint J 2021;103-B(8):1339–1344

In a clinical setting, there is a need for simple gait kinematic measurements to facilitate objective unobtrusive patient monitoring. The objective of this study is to determine if a learned classification model's output can be used to monitor a person's recovery status post-TKA. The gait kinematics of 20 asymptomatic and 17 people with TKA were measured using a full-body Xsens model. 1. The experimental group was measured at 6 weeks, 3, 6, and 12 months post-surgery. Joint angles of the ankle, knee, hip, and spine per stride (10 strides) were extracted from the Xsens software (MVN Awinda studio 4.4). 1. . Statistical features for each subject at each evaluation moment were derived from the kinematic time-series data. We normalised the features using standard scaling. 2. We trained a logistic regression (LR) model using L1-regularisation on the 6 weeks post-surgery data2–4. After training, we applied the trained LR- model to the normalised features computed for the subsequent timepoints. The model returns a score between 0 (100% confident the person is an asymptomatic control) and 1 (100% confident this person is a patient). The decision boundary is set at 0.5. The classification accuracy of our LR-model was 94.58%. Our population's probability of belonging to the patient class decreases over time. At 12 months post-TKA, 38% of our patients were classified as asymptomatic

Hip dysplasia has traditionally been classified based on the lateral centre edge angle (LCEA). A recent meta-analysis demonstrated no definite consensus and a significant heterogeneity in LCEA values used in various studies to define hip dysplasia and borderline dysplasia. To overcome the shortcomings of classifying hip dysplasia based on just LCEA, a comprehensive classification for adult acetabular dysplasia (CCAD) was proposed to classify symptomatic hips into three discrete prototypical patterns of hip instability, lateral/global, anterior, or posterior. The purpose of this study was to assess the reliability of this recently published CCAD. One thirty four consecutive hips that underwent a PAO were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior or psosterior. Based on the prevalence of individual dysplasia and using KappaSize R package version 1.1, seventy four cases were necessary for reliability analysis: 44 dysplastic and 30 normal hips were randomly selected. Six blinded fellowship trained raters were then provided with the classification system and they looked at the x-rays (74 images) at two separate time points (minimum two weeks apart) to classify the hips using standard PACS measurements. Thereafter, a consensus meeting was held where a simplified flow diagram was devised before a third reading by four raters using a separate set of 74 radiographs took place. Intra-rater results per surgeon between Time 1 and Time 2 showed substantial to almost perfect agreement amongst the raters. With respect to inter-rater reliability, at time 1 and time 2, there was substantial agreement overall between all surgeons (kappa of 0.619 for time 1 and 0,623 for time 2). Posterior and anterior rating categories had moderate and fair agreement at time 1 and time 2, respectively. At time 3, overall reliability (kappa of 0.687) and posterior and anterior rating improved from Time 1 and Time 2. The comprehensive classification system provides a reliable way to identify three categories of acetabular dysplasia that are well-aligned with surgical management. The term borderline dysplasia should no longer be used

Acute spinal cord injury (SCI) is most often secondary to trauma, and frequently presents with associated injuries. A neurological examination is routinely performed during trauma assessment, including through Advanced Trauma Life Support (ATLS). However, there is no standard neurological assessment tool specifically used for trauma patients to detect and characterize SCI during the initial evaluation. The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) is the most comprehensive and popular tool for assessing SCI, but it is not adapted to the acute trauma patients such that it is not routinely used in that setting. Therefore, the objective is to develop a new tool that can be used routinely in the initial evaluation of trauma patients to detect and characterize acute SCI, while preserving basic principles of the ISNCSCI. The completion rate of the ISCNSCI during the initial evaluation after an acute traumatic SCI was first estimated. Using a modified Delphi technique, we designed the Montreal Acute Classification of Spinal Cord Injuries (MAC-SCI), a new tool to detect and characterize the completeness (grade) and level of SCI in the polytrauma patient. The ability of the MAC-SCI to detect and characterize SCI was validated in a cohort of 35 individuals who have sustained an acute traumatic SCI. The completeness and neurological level of injury (NLI) were assessed by two independent assessors using the MAC-SCI, and compared to those obtained with the ISNCSCI. Only 33% of patients admitted after an acute traumatic SCI had a complete ISNCSCI performed at initial presentation. The MAC-SCI includes 53 of the 134 original elements of the ISNCSCI which is 60% less. There was a 100% concordance between the severity grade derived from the MAC-SCI and from the ISNCSCI. Concordance of the NLI within two levels of that obtained from the ISNCSCI was observed in 100% of patients with the MAC-SCI and within one level in 91% of patients. The ability of the MAC-SCI to discriminate between cervical (C0 to C7) vs. thoracic (T1 to T9) vs. thoraco-lumbar (T10 to L2) vs. lumbosacral (L3 to S5) injuries was 100% with respect to the ISNCSCI. The rate of completion of the ISNCSCI is low at initial presentation after an acute traumatic SCI. The MAC-SCI is a streamlined tool proposed to detect and characterize acute SCI in polytrauma patients, that is specifically adapted to the acute trauma setting. It is accurate for determining the completeness of the SCI and localize the NLI (cervical vs. thoracic vs. lumbar). It could be implemented in the initial trauma assessment protocol to guide the acute management of SCI patients

Acute spinal cord injury (SCI) is most often secondary to trauma, and frequently presents with associated injuries. A neurological examination is routinely performed during trauma assessment, including through Advanced Trauma Life Support (ATLS). However, there is no standard neurological assessment tool specifically used for trauma patients to detect and characterize SCI during the initial evaluation. The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) is the most comprehensive and popular tool for assessing SCI, but it is not adapted to the acute trauma patients such that it is not routinely used in that setting. Therefore, the objective is to develop a new tool that can be used routinely in the initial evaluation of trauma patients to detect and characterize acute SCI, while preserving basic principles of the ISNCSCI. The completion rate of the ISCNSCI during the initial evaluation after an acute traumatic SCI was first estimated. Using a modified Delphi technique, we designed the Montreal Acute Classification of Spinal Cord Injuries (MAC-SCI), a new tool to detect and characterize the completeness (grade) and level of SCI in the polytrauma patient. The ability of the MAC-SCI to detect and characterize SCI was validated in a cohort of 35 individuals who have sustained an acute traumatic SCI. The completeness and neurological level of injury (NLI) were assessed by two independent assessors using the MAC-SCI, and compared to those obtained with the ISNCSCI. Only 33% of patients admitted after an acute traumatic SCI had a complete ISNCSCI performed at initial presentation. The MAC-SCI includes 53 of the 134 original elements of the ISNCSCI which is 60% less. There was a 100% concordance between the severity grade derived from the MAC-SCI and from the ISNCSCI. Concordance of the NLI within two levels of that obtained from the ISNCSCI was observed in 100% of patients with the MAC-SCI and within one level in 91% of patients. The ability of the MAC-SCI to discriminate between cervical (C0 to C7) vs. thoracic (T1 to T9) vs. thoraco-lumbar (T10 to L2) vs. lumbosacral (L3 to S5) injuries was 100% with respect to the ISNCSCI. The rate of completion of the ISNCSCI is low at initial presentation after an acute traumatic SCI. The MAC-SCI is a streamlined tool proposed to detect and characterize acute SCI in polytrauma patients, that is specifically adapted to the acute trauma setting. It is accurate for determining the completeness of the SCI and localize the NLI (cervical vs. thoracic vs. lumbar). It could be implemented in the initial trauma assessment protocol to guide the acute management of SCI patients

Acute spinal cord injury (SCI) is most often secondary to trauma, and frequently presents with associated injuries. A neurological examination is routinely performed during trauma assessment, including through Advanced Trauma Life Support (ATLS). However, there is no standard neurological assessment tool specifically used for trauma patients to detect and characterize SCI during the initial evaluation. The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) is the most comprehensive and popular tool for assessing SCI, but it is not adapted to the acute trauma patients such that it is not routinely used in that setting. Therefore, the objective is to develop a new tool that can be used routinely in the initial evaluation of trauma patients to detect and characterize acute SCI, while preserving basic principles of the ISNCSCI. The completion rate of the ISCNSCI during the initial evaluation after an acute traumatic SCI was first estimated. Using a modified Delphi technique, we designed the Montreal Acute Classification of Spinal Cord Injuries (MAC-SCI), a new tool to detect and characterize the completeness (grade) and level of SCI in the polytrauma patient. The ability of the MAC-SCI to detect and characterize SCI was validated in a cohort of 35 individuals who have sustained an acute traumatic SCI. The completeness and neurological level of injury (NLI) were assessed by two independent assessors using the MAC-SCI, and compared to those obtained with the ISNCSCI. Only 33% of patients admitted after an acute traumatic SCI had a complete ISNCSCI performed at initial presentation. The MAC-SCI includes 53 of the 134 original elements of the ISNCSCI which is 60% less. There was a 100% concordance between the severity grade derived from the MAC-SCI and from the ISNCSCI. Concordance of the NLI within two levels of that obtained from the ISNCSCI was observed in 100% of patients with the MAC-SCI and within one level in 91% of patients. The ability of the MAC-SCI to discriminate between cervical (C0 to C7) vs. thoracic (T1 to T9) vs. thoraco-lumbar (T10 to L2) vs. lumbosacral (L3 to S5) injuries was 100% with respect to the ISNCSCI. The rate of completion of the ISNCSCI is low at initial presentation after an acute traumatic SCI. The MAC-SCI is a streamlined tool proposed to detect and characterize acute SCI in polytrauma patients, that is specifically adapted to the acute trauma setting. It is accurate for determining the completeness of the SCI and localize the NLI (cervical vs. thoracic vs. lumbar). It could be implemented in the initial trauma assessment protocol to guide the acute management of SCI patients

The most common classification of periprosthetic femoral fractures is the Vancouver classification. The classification has been validated by multiple centers. Fractures are distinguished by location, stability of the femoral component, and bone quality. Although postoperative and intraoperative fractures are classified using the same three regions, the treatment algorithm is slightly different. Type A fractures involve the greater and lesser trochanter. Fractures around the stem or just distal to the stem are Type B and subcategorised depending on stem stability and bone quality. Type C fractures are well distal to the stem and are treated independent of the stem with standard fixation techniques. The majority of fractures are either B1 (stable stem) or B2 (unstable stem). The stem is retained and ORIF of the fracture performed for B1 fractures. B2 and B3 fractures require stem revision with primary stem fixation distal to the fracture. Intraoperative fractures use the same A, B, C regions but are subtyped 1–3 as cortical perforations, nondisplaced, and displaced unstable fractures, respectively. With the exception of A1 intraoperative fractures all other intraoperative fractures require surgical treatment. A recent publication utilizing a New York state registry highlighted the patient risk of mortality associated with periprosthetic hip fractures. One month, 6 month and 1 year mortality was 3.2%, 3.8% and 9.7%, respectively. The mortality risk was lower for periprosthetic fractures treated with ORIF at 1 and 6 months compared to fractures requiring revision total hip

Aims. The Oswestry-Bristol Classification (OBC) is an MRI-specific assessment tool to grade trochlear dysplasia. The aim of this study is to validate clinically the OBC by demonstrating its use in selecting treatments that are safe and effective. Methods. The OBC and the patellotrochlear index were used as part of the Oswestry Patellotrochlear Algorithm (OPTA) to guide the surgical treatment of patients with patellar instability. Patients were assigned to one of four treatment groups: medial patellofemoral ligament reconstruction (MPFLr); MPFLr + tibial tubercle distalization (TTD); trochleoplasty; or trochleoplasty + TTD. A prospective analysis of a longitudinal patellofemoral database was performed. Between 2012 and 2018, 202 patients (233 knees) with a mean age of 24.2 years (SD 8.1), with recurrent patellar instability were treated by two fellowship-trained consultant sports/knee surgeons at The Robert Jones and Agnes Hunt Orthopaedic Hospital. Clinical efficacy of each treatment group was assessed by Kujala, International Knee Documentation Committee (IKDC), and EuroQol five-dimension questionnaire (EQ-5D) scores at baseline, and up to 60 months postoperatively. Their safety was assessed by complication rate and requirement for further surgery. The pattern of clinical outcome over time was analyzed using mixed regression modelling. Results. In all, 135 knees (mean age 24.9 years (SD 9.4)) were treated using a MPFLr. Ten knees (7.4%) required additional surgery. A total of 50 knees (mean age 24.4 years (SD 6.3)) were treated using MPFLr + TTD. Ten (20%) required additional surgery. A total of 20 knees (mean age 19.5 years (SD 3.0)) were treated using trochleoplasty + TTD. Three patients (15%) required additional surgery. In each treatment group, there was a significant improvement in Kujala, IKDC, and EQ-5D at one year postoperatively (p < 0.001) with a recognized level of overall complication rate. Conclusion. The OBC is a valid assessment tool to grade patients with trochlear dysplasia and, when used as part of the OPTA, helps to determine treatments that are safe and effective. This fulfils the requirements for its application in mainstream clinical practice. Cite this article: Bone Joint J 2021;103-B(10):1586–1594

Though knee osteoarthritis (OA) is diagnosed and monitored radiographically, full thickness cartilage loss (FTCL) has rarely been correlated with radiographic classification. This study aims to analyse which classification system correlates best with FTCL and assessing their reliability. Prospective study of 300 consecutive patients undergoing total knee arthroplasty (TKA) for OA. Two blinded examiners independently graded preoperative radiographs using 5 systems: Kellgren-Lawrence (KL); International Knee Documentation Committee (IKDC); Fairbank; Brandt; and Ahlback. Interobserver agreement was assessed using the intraclass correlation coefficient. Intraoperatively, anterior cruciate ligament (ACL) status and FTCL in 16 regions of interest were recorded. Radiographic classification and FTCL were correlated using the Spearman correlation coefficient. On average, each knee had 6.8±3.1 regions of FTCL, most common medially. The commonest patterns of FTCL were medial with patellofemoral (48%) and tricompartmental (30%). ACL status was associated with pattern of FTCL (p=0.02). All classification systems demonstrated moderate ICC, but this was highest for IKDC: whole knee 0.68 (95%CI 0.60–0.74); medial compartment 0.84 (0.80–0.87); and lateral compartment 0.79 (0.73–0.83). Correlation with FTCL was strongest for Ahlback (Spearman rho 0.27–0.39) and KL (0.30–0.33), though all systems demonstrated medium correlation. The Ahlback was the most discriminating in severe OA. Osteophyte presence in the medial compartment had high positive predictive value for FTCL, but not in the lateral compartment. The Ahlback and KL systems had the highest correlation with confirmed cartilage loss. However, the IKDC system displayed best interobserver reliability, with favourable correlation with FTCL in medial and lateral compartments, though less discriminating in severe disease

Aims. The burden of revision total hip arthroplasty (rTHA) continues to grow. The surgery is complex and associated with significant costs. Regional rTHA networks have been proposed to improve outcomes and to reduce re-revisions, and therefore costs. The aim of this study was to accurately quantify the cost and reimbursement for a rTHA service, and to assess the financial impact of case complexity at a tertiary referral centre within the NHS. Methods. A retrospective analysis of all revision hip procedures was performed at this centre over two consecutive financial years (2018 to 2020). Cases were classified according to the Revision Hip Complexity Classification (RHCC) and whether they were infected or non-infected. Patients with an American Society of Anesthesiologists (ASA) grade ≥ III or BMI ≥ 40 kg/m. 2. are considered “high risk” by the RHCC. Costs were calculated using the Patient Level Information and Costing System (PLICS), and remuneration based on Healthcare Resource Groups (HRG) data. The primary outcome was the financial difference between tariff and cost per patient episode. Results. In all, 199 revision episodes were identified in 168 patients: 25 (13%) least complex revisions (H1); 110 (55%) complex revisions (H2); and 64 (32%) most complex revisions (H3). Of the 199, 76 cases (38%) were due to infection, and 78 patients (39%) were “high risk”. Median length of stay increased significantly with case complexity from four days to six to eight days (p = 0.006) and for revisions performed for infection (9 days vs 5 days; p < 0.001). Cost per episode increased significantly between complexity groups (p < 0.001) and for infected revisions (p < 0.001). All groups demonstrated a mean deficit but this significantly increased with revision complexity (£97, £1,050, and £2,887 per case; p = 0.006) and for infected failure (£2,629 vs £635; p = 0.032). The total deficit to the NHS Trust over two years was £512,202. Conclusion. Current NHS reimbursement for rTHA is inadequate and should be more closely aligned to complexity. An increase in the most complex rTHAs at major revision centres will likely place a greater financial burden on these units. Cite this article: Bone Jt Open 2023;4(8):559–566

Aims. We have reviewed the published classifications of long-bone osteomyelitis. This review demonstrated the limitations and poor recognition of existing classifications. We have designed a new system which includes four easily identifiable variables which are Bone involvement, Antimicrobial availability, Soft tissue coverage and Host status. This is called the B.A.C.H. classification system. In this study, we aim to retrospectively validate this classification in a cohort of osteomyelitis cases. Methods. We identified 100 patients who had received surgery for osteomyelitis between 2013–2015 in a single specialist centre. Each patient was classified retrospectively by two assessors who were not involved in the initial patient care. Osteomyelitis was confirmed in each patient by a validated composite protocol. Results. All patients in this series could be classified using each of the B.A.C.H. variables. Seventy-four patients were categorised as B1, 13 as B2 and 13 as B3. Thirty-four patients revealed no growth of microorganisms (Ax). Fifty-four were A1, 11 A2 and one patient was classified as A3. For rare organisms (e.g. Corynebacterium spp.), classification required specialised infectious disease knowledge. Twenty-four patients needed soft tissue procedures (C2) and 76 had their wound closed primarily (C1). Twenty patients did not need optimisation prior to surgery and were deemed as H1. The remaining 80 patients needed optimisation prior to surgery and were deemed as H2. Conclusions. All patients were classifiable when using the B.A.C.H. system. This system offers a simple method of stratifying long-bone osteomyelitis and may give an indication of severity and the need for specialist intervention. However, there were difficulties in classification of rare causative organisms. This validation has been performed in a single specialist centre for osteomyelitis and requires both internal prospective and external validation to evaluate its reproducibility

Aim. The B.A.C.H. system is a new classification for long bone osteomyelitis. It uses the four key inter-disciplinary components of osteomyelitis, namely, bone involvement, anti-microbial options, soft tissue status and host status. This study aims to assess the inter-user reliability of using the B.A.C.H. classification system. Method. We identified 20 patients who had a diagnosis of long bone osteomyelitis using a previously validated composite protocol. For each patient, osteomyelitis history, past-medical history, clinical imaging (including radiology report), photographs of the affected limb and microbiology were presented to clinical observers on an online form. Thirty observers, varying in clinical experience (training grades and consultants, with a variety of exposure to osteomyelitis) and specialty (orthopaedic surgery, infectious diseases and plastic surgery) were asked to rate the twenty cases of osteomyelitis. Before rating, an explanation of how to use the classification system was given to the observers, in a structured ‘user key’. The responses were assessed by accuracy against a reference value and Fleiss' kappa value (Fκ). Results. The 30 users individually classified all 20 cases. The observers comprised 14 orthopaedic surgeons, 13 physicians (either microbiology, infectious diseases or anesthetists) and 3 plastic surgeons. The users had a variety of exposure to osteomyelitis ranging from less than one case per month to greater than one case per week. The accuracy across all variables was 86.2% (95% CI 83.9% – 88.6%, SD 6.2%), with the ‘C’ variable scoring the highest at 92.5% (95% CI 88.5% – 95.6%, SD 8.2%) and the ‘B’ variable scoring the lowest at 77.0% (95% CI 71.2% – 82.8%, SD 15.5%). The variable with the highest agreement between users was the anti-microbial options with a Fκ of 0.815 (95% CI 0.811 – 0.819) which correlated to an ‘almost perfect agreement’. Despite this, the classification of the more complex isolates proved problematic. The most variability was seen in the bone involvement variable with an Fκ of 0.479 (95% CI 0.475 – 0.483) which correlated to a ‘fair agreement’. Conclusions. The B.A.C.H. classification system for long bone osteomyelitis demonstrated a substantial agreement between observers according to the Fκ value. This was supported by a high level of accuracy of classification within each of the variables. The bone involvement category had a moderate agreement amongst users. This could be due to the nature of the 2-D presentation of cases within the online form. The Fκ was not influenced by clinical experience or clinical specialty, suggesting that B.A.C.H. is applicable by all levels. Further work is required to assess and optimise the descriptions of the bone involvement and anti-microbial options variables

Degenerative lumbar spondylolisthesis (DLS) is a common condition with many available treatment options. The Degenerative Spondylolisthesis Instability Classification (DSIC) scheme, based on a systematic review of best available evidence, was proposed by Simmonds et al. in 2015. This classification scheme proposes that the stability of the patient's pathology be determined by a surgeon based on quantitative and qualitative clinical and radiographic parameters. The purpose of the study is to utilise machine learning to classify DLS patients according to the DSIC scheme, offering a novel approach in which an objectively consistent system is employed. The patient data was collected by CSORN between 2015 and 2018 and included 224 DLS surgery cases. The data was cleaned by two methods, firstly, by deleting all patient entries with missing data, and secondly, by imputing the missing data using a maximum likelihood function. Five machine learning algorithms were used: logistic regression, boosted trees, random forests, support vector machines, and decision trees. The models were built using Python-based libraries and trained and tested using sklearn and pandas librairies. The algorithms were trained and tested using the two data sets (deletion and imputation cleaning methods). The matplotlib library was used to graph the ROC curves, including the area under the curve. The machine learning models were all able to predict the DSIC grade. Of all the models, the support vector machine model performed best, achieving an area under the curve score of 0.82. This model achieved an accuracy of 63% and an F1 score of 0.58. Between the two data cleaning methods, the imputation method was better, achieving higher areas under the curve than the deletion method. The accuracy, recall, precision, and F1 scores were similar for both data cleaning methods. The machine learning models were able to effectively predict physician decision making and score patients based on the DSIC scheme. The support vector machine model was able to achieve an area under the curve of 0.82 in comparison to physician classification. Since the data set was relatively small, the results could be improved with training on a larger data set. The use of machine learning models in DLS classification could prove to be an efficient approach to reduce human bias and error. Further efforts are necessary to test the inter- and intra-observer reliability of the DSIC scheme, as well as to determine if the surgeons using the scheme are following DLS treatment recommendations

Aims. The purpose of this study was to assess the reliability and responsiveness to hip surgery of a four-point modified Care and Comfort Hypertonicity Questionnaire (mCCHQ) scoring tool in children with cerebral palsy (CP) in Gross Motor Function Classification System (GMFCS) levels IV and V. Methods. This was a population-based cohort study in children with CP from a national surveillance programme. Reliability was assessed from 20 caregivers who completed the mCCHQ questionnaire on two occasions three weeks apart. Test-retest reliability of the mCCHQ was calculated, and responsiveness before and after surgery for a displaced hip was evaluated in a cohort of children. Results. Test-retest reliability for the overall mCCHQ score was good (intraclass correlation coefficient 0.78), and no dimension demonstrated poor reliability. The surgical intervention cohort comprised ten children who had preoperative and postoperative mCCHQ scores at a minimum of six months postoperatively. The mCCHQ tool demonstrated a significant improvement in overall score from preoperative assessment to six-month postoperative follow-up assessment (p < 0.001). Conclusion. The mCCHQ demonstrated responsiveness to intervention and good test-retest reliability. The mCCHQ is proposed as an outcome tool for use within a national surveillance programme for children with CP. Cite this article: Bone Jt Open 2023;4(8):580–583

Background. Total hip arthroplasty (THA) in patients with congenital dysplasia of the hip (CDH) is complex and challenging. The Crowe and Hartofilakidis classification systems are the most commonly used. However, neither encompasses the whole spectrum of disease and deformity and therefore does not guide modern surgical options. We present a new classification system which aims to guide surgical strategy by focusing on the three main areas of disease and deformity: Cup defect; De-rotation of femoral neck ante-version; Height of femoral subluxation. Each component is graded from 1–3 based on the severity of deformity and the potential surgical strategy required (with 3 being the most severe). A total numerical score will reflect the overall degree of difficulty which may be used when assessing surgical outcomes. The aim of this study is to assess the reliability of this new adult CDH classification system in the setting of THA. Study design and Methods. A sample size calculation showed 28 evaluations were required to reach a power of 85% (based on a kappa value of 0.4). The anterior-posterior pelvis and lateral hip radiographs of 30 hips, in 26 patients were evaluated by three Consultant Orthopaedic Surgeons using the classification detailed in table 1. A second evaluation, with the case order randomised, was performed after a minimum period of 1month. Randolph's free multi-rater Kappa co-efficient was used to assess for inter and intra- observer reliability and 95% confidence intervals were calculated. Results. The results of the Inter and intra–observer reliability for each classification component and for each rater respectively are shown in table 2 and 3. Conclusions. In comparison with other studies our reliability results were poorer when compared to the Hartofilakidis and Crowe classification systems. It was reported by the participants that our system enabled a more logical breakdown of the component deformities to address when performing THA in these hips. As with the Paprosky system for revision hip arthroplasty, this X-ray classification is intended as a practical pre-op guide to planning for all eventualities. Limitations due to level of observer experience and finer intra-operative judgements may alter the final result, but the essence is to understand the anatomical pitfalls enabling appropriate surgical planning and a total score against which to judge outcomes. For any figures or tables, please contact the authors directly

Purpose of study and background. Clinical researchers use Pfirrmann classification for grading intervertebral disc degeneration radiologically. Basic researchers have access to morphology and instead use the Thompson score. The aim of this study was to assess the inter-observer reliability of both classifications, along with their correlation. Methods and Results. We obtained T2-weighted MR images of 80 human lumbar intervertebral discs with various stages of degeneration to assess the Pfirrmann-score. Then the discs were dissected midsagittally to obtain the Thompson-score. The observers were typical users of both grading systems: a spine surgeon, radiology resident, orthopaedic resident, and a basic scientist, all experts on intervertebral disc degeneration. Cohen's kappa (CK) was used to determine inter-observer reliability, and intra-class correlation (ICC) as a measure for the variation between the outcomes. For the Thompson score, the average CK was 0.366 and ICC score 0.873. The average inter-observer reliability for the Pfirrmann score was 0.214 (CK) and 0.790 (ICC). Comparing the grading systems, the intra-observer agreement was 0.240 (CK) and 0.685 (ICC). Conclusion. With substantial variation between observers, the inter-observer agreements for the Pfirrmann and Thompson grading systems were moderate. This may explain the poor relationship between radiological and clinical observations in patients and raises questions about the validity of the Pfirrmann score. The mediocre intra-observer agreement between the Pfirrmann and Thompson score shows that there is no clear definition of intervertebral disc degeneration. The field is in need for a new, objective and quantitative classification system to better define and evaluate disc degeneration. There are no conflicts of interest. Funded in part by Annafonds Netherlands and Dutch Spine Society

Arthroscopic management of femoroacetabular impingement (FAI) has become the mainstay of treatment. However, chondral lesions are frequently encountered and have become a determinant of less favourable outcomes following arthroscopic intervention. The aim of this systematic review and meta-analysis was to assess the outcomes of hip arthroscopy (HA) in patients with FAI and concomitant chondral lesions classified as per Outerbridge. A systematic search was performed using the PRISMA guidelines on four databases including MEDLINE, EMBASE, Cochrane Library and Web of Science. Studies which included HA as the primary intervention for management of FAI and classified chondral lesions according to the Outerbridge classification were included. Patients treated with open procedures, for osteonecrosis, Legg-Calve-Perthes disease, and previous ipsilateral hip fractures were excluded. From a total of 863 articles, twenty-four were included for final analysis. Demographic data, PROMs, and radiological outcomes and rates of conversion to total hip arthroplasty (THA) were collected. Risk of bias was assessed using ROBINS-I. Improved post-operative PROMs included mHHS (mean difference:-2.42; 95%CI:-2.99 to −1.85; p<0.001), NAHS (mean difference:-1.73; 95%CI: −2.23 to −1.23; p<0.001), VAS (mean difference: 2.03; 95%CI: 0.93-3.13; p<0.001). Pooled rate of revision surgery was 10% (95%CI: 7%-14%). Most of this included conversion to THA, with a 7% pooled rate (95%CI: 4%-11%). Patients had worse PROMs if they underwent HA with labral debridement (p=0.015), had Outerbridge 3 and 4 lesions (p=0.012), concomitant lesions of the femoral head and acetabulum lesions (p=0.029). Reconstructive cartilage techniques were superior to microfracture (p=0.042). Even in concomitant lesions of the femoral head and acetabulum, employing either microfracture or cartilage repair/reconstruction provided a benefit in PROMs (p=0.027). Acceptable post-operative outcomes following HA with labral repair/reconstruction and cartilage repair in patients with FAI and concomitant moderate-to-severe chondral lesions, can be achieved. Patients suffering from Outerbridge 3 and 4 lesions, concomitant acetabular rim and femoral head chondral lesions that underwent HA with labral debridement, had worse PROMs. Reconstructive cartilage techniques were superior to microfracture. Even in concomitant acetabular and femoral head chondral lesions, employing either microfracture or cartilage repair/reconstruction was deemed to provide a benefit in PROMs

Introduction. Treatment of prosthetic joint infection (PJI) following total knee arthroplasty (TKA) may guided by PJI classification, taking into account infection duration and potential for biofilm formation. Debridement, antibiotics and implant retention (DAIR) is recommended for ‘post-operative’ and ‘acute’ haematogenous PJI. However, the time cut-off for ‘post-operative’ PJI varies across classification systems. Furthermore, poor DAIR success rates have been reported in acute haematogenous PJIs. This study aimed to determine the success of DAIR in a large cohort of PJIs, and assess the utility of current classification systems for predicting DAIR outcomes. Method. In this multicentre retrospective, cohort study, we identified 230 patients undergoing DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors were identified, and PJI subtype, post-operative antibiotic regime and treatment outcomes were recorded. Statistical analysis was performed to identify factors associated with failed DAIR, and success rates were analysed by multiple classification systems using receiver operating characteristic (ROC) curves. Results. At average follow-up of 6.9 years, DAIR failed in 46% of cases. ROC analysis found 3 month and 1 year cut-offs for ‘post-operative’ PJIs were equally predictive of outcomes (AUC=0.63). On multivariate survival analysis, DAIR failed in 63% of late haematogenous PJIs (implant age>1 year) compared to 36% of early (<1year) PJIs (OR=1.78, p=0.01). Staphylococcus aureus (OR=4.70, p<0.001) and gram negative infections (OR=2.56, p=0.031) were risk factors for DAIR failure in late PJIs. Conclusions. We found a high failure rate in late infections following TKA, irrespective of their classification as ‘acute haematogenous’ or ‘chronic’. Higher DAIR success rates were seen with implant age <1year. These findings call into question the utility of current classification systems based on duration of bacterial presence. For late infections (>1year), PJI caused by S. aureus or gram negative bacteria have a higher failure rate when treated with DAIR

Aim. Chronic osteomyelitis of long bones is one of the most severe complications in orthopedics. Different options exist for treatment of this disease, however there is still no generally accepted comprehensive protocol that could potentially guide us in each particular step. There are many classifications that were designed to help us to make clinical decision, however even the most widely used Cierny-Mader classification does not count more a half of factors, assessment of which is essential for choosing the best treatment plan. This fact may be explained by the complexity of the disease process, diversity of treatment options and multistage approach to the management of these patients. Therefore, the purpose of this study was to work out a treatment protocol and clinical classification system, which will improve final outcomes in patients with chronic osteomyelitis of long bones. Method. Three orthopedic surgeons and one general surgeon who specialize on bone and joint infection independently of each other made a review of literature dedicated to the topic of chronic osteomyelitis. Each surgeon created a list of factors that are essential to assess for successful treatment of chronic osteomyelitis. After four lists were thoroughly matched and discussed, 10 most important factors were defined. Each surgeon proposed his own protocol of treatment, based on existent data and own experience. All four protocols were discussed and analyzed to come up with new the most comprehensive one. Therefore, the new protocol was created. After the list of factors and protocol were created, surgeons independently of each other defined the most important factors for every stage in the new protocol. Thus new multi-stage classification of chronic osteomyelitis (MSC-CO) was proposed. Results. We have defined the most important factors influencing on the decision making process in treatment of chronic osteomyelitis of long bones. The new comprehensive protocol and multi-stage clinical classification were developed. Conclusions. We assume, that the proposed tools may improve the results of chronic osteomyelitis treatment. However, the clinical trials should be conducted to assess the utility of new treatment protocol and MSC-CO in daily practice

Introduction. Classification systems are used throughout Trauma and Orthopaedic (T&O) surgery, designed to be used for communication, planning treatment options, predicting outcomes and research purposes. As a result the majority of T&O knowledge is based upon such systems with most of the published literature using classifications. Therefore we wanted to investigate the basis for the classification culture in our specialty by reviewing Orthopaedic classifications and the literature to assess whether the classifications had been independently validated. Methods. 185 published classification systems within T&O were selected. The original publication for each classification system was reviewed to assess whether any validation process had been performed. Each paper was reviewed to see if any intra-observer or inter-observer error was reported. A PubMed search was then conducted for each classification system to assess whether any independent validation had been performed. Any measurement of validation and error was recorded. Results. Four of the 185 classifications (2.1%) had a validation process described in the initial paper that introduced that classification to the literature. 54 (29.1%) of the classifications had a related study that independently assessed the classification for validity. Of these 54, only 10 (18.5%) demonstrated either an intra-observer or inter-observer error that is described as excellent (kappa score >0.8). Only 2 classification systems of the 54 (3.7%) were shown to have both intra-observer and inter-observer errors as excellent, meaning only 2 of the 185 classification systems reviewed (1.1%) have been shown to be highly reproducible. Conclusion. Over 70% of classification systems in T&O have never been independently validated and assessed for intra-observer and inter-observer error. Of those that have, only 2 are excellent. Such a finding raises questions about the use of classification systems within T&O and queries the use of classification systems in the literature as part of evidence based medicine

Introduction. During revision total hip arthroplasty, successful treatment of acetabular bone loss with an associated chronic pelvic discontinuity is dependent upon the remaining bone stock, stability of the construct, potential for biologic fixation, and healing of the discontinuity. Several techniques have been described for the treatment of this clinical entity; the authors recommend the use of acetabular distraction technique in conjunction with a jumbo cup with or without augments. The authors recently evaluated the minimum two-year follow-up of acetabular distraction technique for the treatment of chronic pelvic discontinuity. In the process, a chronic pelvic discontinuity classification was created based on the type of reconstruction required. The purpose of this study is to introduce the initial observations of this novel classification system. Methods. Patients from two academic institutions undergoing acetabular distraction for chronic pelvic discontinuity were identified between January 2002 and December 2013 with minimum 2-year follow-up. Radiographs at latest follow-up were compared to serial radiographs from the index surgery. Data was collected by chart review in accordance with institutional IRB protocol from both institutions. Results. A cohort of 32 patients had minimum 2-year (range, 2.1–13.3 years) follow-up. Mean patient age was 67 years (range, 44–86) and 87% were female. All patients had a chronic pelvic discontinuity with the following bone loss patterns: 7 (22%) type IIC, 5 (15%) type IIIA and 20 (63%) type IIIB. At time of final follow-up, radiographs demonstrated 22 of 32 patients (69%) had evidence of a healed discontinuity. Chronic Pelvic Discontinuity Classification. The classification mirrors the Paprosky classification and requires a more complex reconstruction with each progressive type. For the 20 patients with a type IIIB acetabular bone loss pattern, the new classification was applied. The distribution of classification types was as follows: type I 6 (30%); type II 5 (25%); type IIIA 4 (20%); type IIIB 5 (25%); and type IV 0. Overall, 70% (14) patients required the use of an augment for acetabular reconstruction. Conclusions. Acetabular distraction has been established as an effective method by which to treat chronic pelvic discontinuity. The new classification helps to determine the complexity of reconstruction required for each discontinuity, especially when assessing the most severe acetabular defects (Paprosky IIIB). The authors advocate acetabular distraction with a jumbo cup and modular porous metal augments as the preferred treatment for acetabular bone loss with associated chronic pelvic discontinuity. According to the new classification, the likelihood of utilizing augment(s) increases with severity of bone loss. Future studies are required to validate this new chronic pelvic discontinuity classification

Introduction. Gait laboratory measurement of whole-body kinematics and ground reaction forces during a wide range of activities is frequently performed in joint replacement patient diagnosis, monitoring, and rehabilitation programs. These data are commonly processed in musculoskeletal modeling platforms such as OpenSim and Anybody to estimate muscle and joint reaction forces during activity. However, the processing required to obtain musculoskeletal estimates can be time consuming, requires significant expertise, and thus seriously limits the patient populations studied. Accordingly, the purpose of this study was to evaluate the potential of deep learning methods for estimating muscle and joint reaction forces over time given kinematic data, height, weight, and ground reaction forces for total knee replacement (TKR) patients performing activities of daily living (ADLs). Methods. 70 TKR patients were fitted with 32 reflective markers used to define anatomical landmarks for 3D motion capture. Patients were instructed to perform a range of tasks including gait, step-down and sit-to-stand. Gait was performed at a self-selected pace, step down from an 8” step height, and sit-to-stand using a chair height of 17”. Tasks were performed over a force platform while force data was collected at 2000 Hz and a 14 camera motion capture system collected at 100 Hz. The resulting data was processed in OpenSim to estimate joint reaction and muscle forces in the hip and knee using static optimization. The full set of data consisted of 135 instances from 70 patients with 63 sit-to-stands, 15 right-sided step downs, 14 left-sided step downs, and 43 gait sequences. Two classes of neural networks (NNs), a recurrent neural network (RNN) and temporal convolutional neural network (TCN), were trained to predict activity classification from joint angle, ground reaction force, and anthropometrics. The NNs were trained to predict muscle and joint reaction forces over time from the same input metrics. The 135 instances were split into 100 instances for training, 15 for validation, and 20 for testing. Results. The RNN and TCN yielded classification accuracies of 90% and 100% on the test set. Correlation coefficients between ground truth and predictions from the test set ranged from 0.81–0.95 for the RNN, depending on the activity. Predictions from both NNs were qualitatively assessed. Both NNs were able to effectively learn relationships between the input and output variables. Discussion. The objective of the study was to develop and evaluate deep learning methods for predicting patient mechanics from standard gait lab data. The resulting models classified activities with excellent performance, and showed promise for predicting exact values for loading metrics for a range of different activities. These results indicate potential for real-time prediction of musculoskeletal metrics with application in patient diagnostics and rehabilitation. For any figures or tables, please contact authors directly

Previous classification systems of failure of limb salvage focused primarily on endoprosthetic failures and lacked sufficient depth for the effective study of the causes of failure. In order to address these inadequacies, the International Society of Limb Salvage (ISOLS) formed a committee to recommend revisions of the previous systems. The purpose of this study was to report on their recommendations. The modifications were prepared using an earlier, evidence-based model with subclassification based on the existing medical literature. Subclassification for all five primary types of failure of limb salvage following endoprosthetic reconstruction were formulated and a complementary system was derived for the failure of biological reconstruction. An additional classification of failure in paediatric patients was also described. . Limb salvage surgery presents a complex array of potential mechanisms of failure, and a complete and precise classification of types of failure is required. Earlier classification systems lacked specificity, and the evidence-based system outlined here is designed to correct these weaknesses and to provide a means of reporting failures of limb salvage in order to allow the interpretation of outcome following reconstructive surgery. Cite this article: Bone Joint J 2014;96-B:1436–40

We have tested the reliability of a recently reported classification system of hip morphology in adolescents with cerebral palsy in whom the triradiate cartilage was closed. The classification is a six-grade ordinal scale, based on the measurement of the migration percentage and an assessment of Shenton’s arch, deformity of the femoral head, acetabular deformity and pelvic obliquity. Four paediatric orthopaedic surgeons and four physiotherapists received training in the use of the classification which they applied to the assessment of 42 hip radiographs, read on two separate occasions. The inter- and intra-observer reliability was assessed using the intraclass correlation coefficient and found to be excellent, with it ranging from 0.88 to 0.94. The classification in our study was shown to be valid (based on migration percentage), and reliable. As a result we believe that it can now be used in studies describing the natural history of hip displacement in cerebral palsy, in outcome studies and in communication between clinicians

Abstract. Objectives. Exploring the relationship of gait function pre and post total knee replacement (TKR) in two groups of patients. Methods. Three-dimensional gait analysis was performed at Cardiff University, UK, and Karolinska University Hospital, Sweden, on 29 and 25 non-pathological (NP) volunteers, and 39 and 28 patients with end-stage knee osteoarthritis (OA), respectively. Patients were assessed pre and one-year post-TKR. Data reduction was performed via Principal Component (PC) analysis on twenty-four kinematic and kinetic waveforms in both NP and pre/post-TKR. Cardiff's and Karolinska's cohorts were analysed separately. The Cardiff Classifier, a classification system based on the Dempster-Shafer theory, was trained with the first 3 PCs of each variable for each cohort. The Classifier classifies each participant by assigning them a belief in NP, belief in OA (BOA) and belief in uncertainty, based on their biomechanical features. The correlation between patient's BOA values (range: 0–1, 0 indicates null BOA and 1 high BOA) pre and post-TKR was tested through Spearman's correlation coefficient in each cohort. The related-samples Wilcoxon signed-rank test (α=0.05) determined the significant changes in BOA in each cohort of patients. The Mann-Whitney U test (α=0.05) was run to explore differences between the patients’ cohorts. Results. There were no significant differences between patients’ cohorts in median age (p=0.096), height (p=0.673), weight (p=0.064) or KOOS sub-scores pre or post-TKR (p-value ranged 0.069 to 0.955) but Cardiff's patients had a significantly higher BMI (p=0.047). There was a significant, median decrease of 0.12 and 0.19 in the BOA pre to post TKR (p<0.001) in Cardiff's and Karolinska's patients, respectively. There was a statistically significant, strong positive correlation between the BOA pre and post-TKR (Cardiff:r. s. =0.706, p<0.001; Karolinska:r. s. =0.669, p<0.001). Conclusions. In two distinct cohorts of patients, having a more compromised gait function in end-stage knee OA was correlated with poorer gait function post-TKR

Background. Hip dysplasia has traditionally been classified based on the lateral center edge angle (LCEA). A recent meta-analysis demonstrated no definite consensus and a significant heterogeneity in LCEA values used in various studies to define hip dysplasia and borderline dysplasia. To overcome the shortcomings of classifying hip dysplasia based on just LCEA, a comprehensive classification for adult acetabular dysplasia (CCAD) was proposed to classify symptomatic hips into three discrete prototypical patterns of hip instability; lateral/global, anterior, or posterior. The purpose of this study was to assess the reliability of this recently published CCAD. Methods. One hundred thirty-four consecutive hips that underwent a PAO were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior or posterior. Based on the prevalence of individual dysplasia and using KappaSize R package version 1.1, seventy-four cases were necessary for reliability analysis: 44 dysplastic and 30 normal hips were randomly selected. Five surgeons (3 fellowship trained in hip preservation) did a first reading (Time 1) to classify the hips, followed by four raters for a second reading (Time 2) minimum two weeks apart. Thereafter, a consensus meeting was held where a simplified flow diagram was devised before a third reading by four raters using a separate set of 74 radiographs took place. Results. There was substantial and almost perfect intra-rater agreement for 4 surgeons between Time 1 and Time 2. At time 1 and time 2, there was substantial agreement overall between all surgeons; however, posterior and anterior rating categories had moderate and fair agreement at time 1 and time 2, respectively. At time 3, overall reliability and posterior and anterior rating improved from Time 1 and Time 2. Conclusion. This comprehensive classification system provides a reliable way to identify three categories of acetabular dysplasia that are well-aligned with surgical management. The term borderline dysplasia should no longer be used

Our study was undertaken to assess the inter- and intra-observer variability of the classification system of Sanders for calcaneal fractures. Five consultant orthopaedic surgeons with different subspecialty interests classified CT scans of 28 calcaneal fractures using this classification system. After six months, they reclassified the scans. Kappa statistics were used to analyse the two groups. The interobserver variability of the classification system was 0.32 (95% confidence interval (CI) 0.26 to 0.38). The subclasses were then combined and assessment of agreement between the general classes as a whole gave a kappa value of 0.33 (95% CI 0.25 to 0.41). The mean kappa value for intra-observer variability of the classification system was 0.42 (95% CI 0.22 to 0.62). When the subclasses were combined, it was 0.45 (95% CI 0.21 to 0.65). Our results show that, despite its popularity, the classification system of Sanders has only fair agreement among users

Aim. Bone and joint infections are a serious complication of trauma, surgery and soft tissue infections. However, there are few data presenting patient reported outcome measures for osteomyelitis. A recently proposed method for classification of osteomyelitis, BACH, stratifies patients into ‘uncomplicated’ and ‘complex’, based on four key inter-disciplinary components: . B. one involvement, . A. nti-microbial options, soft-tissue . C. overage and . H. ost status. We aim to correlate the classification severity with patient reported outcomes following osteomyelitis surgery. Method. Seventy-one patients with long-bone osteomyelitis, confirmed using a validated composite protocol, were included. Patients received a single-stage procedure at a specialist bone infection unit. Euro-Qol EQ-5D-3L questionnaires and Visual Analogue Scores (VAS) (0–100) were collected prospectively at baseline, 14 days, 6 weeks, 4 months and 1 year post-operatively. The EQ-5D-3L index score, a composite measure of performance of daily activities, was calculated from the 5 domains of the EQ-5D-3L. BACH was applied retrospectively by two independent clinicians blinded to all patient outcomes. Results. There was significant improvement in VAS (58.2 vs. 78.9, p<0.01) and EQ-5D-3L index (0.284 vs. 0.740, p<0.01) scores from baseline to 1 year. ‘Uncomplicated’ osteomyelitis was associated with significantly higher EQ-5D-3L and VAS at 1 year follow-up when compared to ‘complex’ osteomyelitis (EQ-5D-3L: 0.900 vs. 0.685, p<0.01; VAS: 87.1 vs. 73.6, p<0.05). Patients with cavitary bone involvement (BACH type B1) reported higher outcome scores at all time points when compared to segmental involvement (B2) or infection involving the joint (B3). Good antimicrobial options gave higher outcome scores compared to patients with multi-drug resistant isolates (A2). Patients who had received microvascular tissue transfer (C2) initially reported lower outcome measures but returned to a similar level to patients who had their wounds closed directly (C1) from 6 weeks. Patients with severe co-morbidity (H2) reported lower outcome scores at all time points compared to those who were fit or with well controlled disease (H1). Conclusions. Complex cases of osteomyelitis as defined by BACH classification, had poorer patient reported outcomes compared to uncomplicated cases. This was despite being managed in a centre that specialises in bone and joint infection. This study demonstrates that BACH is helpful for assessing case complexity and prognosis in osteomyelitis

Reoperations may be a better way of tracking adverse outcomes than complications. Repeat surgery causes cost to the system, and often indicate failure of the primary procedure resulting in the patient not achieving the expected improvement in pain and function. Understanding the cause of repeat surgery at the primary site may result in design improvements to implants or improvements to fusion techniques resulting in better outcomes in the future. The COFAS group have designed a reoperation classification system. The purpose of this study was to outline the inter and intra observer reliability of this classification scheme. To verify the inter- and intra-observer reliability of this new coding system, six fellow ship trained practicing foot and ankle Orthopaedic surgeons were asked to classify 62 repeat surgeries from a single surgeons practice. The six surgeons read the operation reports in random order, and reread the reports 2 weeks later in a different order. Reliability was determined using intraclass correlation coefficients (ICC) and proportions of agreement. The agreement between pairs of readings (915 for inter observer for the first and second read – 61 readings with 15 comparisons, observer 1 with observer 2, observer 1 with observer 3, etc) was determined by seeing how often each observer agreed. This was repeated for the 366 ratings for intra observer readings (61 times 6). The inter-observer reliability on the first read had a mean intra-class correlation coefficient (ICC) of 0.89. The range for the 15 comparisons was 0.81 to 1.0. Amongst all 1830 paired codings between two observers, 1605 (88%) were in agreement. Across the 61 cases, 45 (74%) were given the same code by all six observers. However, the difference when present was larger with more observers not agreeing. The inter-observer reliability test on the second read had a mean ICC of 0.94, with a range of 0.90. There were 43 (72%) observations that were the same across all six observers. Of all pairs (915 in total) there was agreement in 804 pairs for the first reading (88%) and disagreement in 111 (12%). For the second reading there was agreement in 801 pairs (86%) and disagreement in 114 (14%). The intra-observer reliability averaged an ICC value of 0.92, with a range of 0.86 to 0.98. The observers agreed with their own previous observations 324 times out of 366 paired readings (89% agreement of pairs). The COFAS classification of reoperations for end stage ankle arthritis was reliable. This scheme potentially could be applied to other areas of Orthopaedic surgery and should replace the Claiden Dindo modifications that do not accurately reflect Orthopaedic outcomes. As complications are hard to define and lack consistent terminology reoperations and resource utilisation (extra clinic visits, extra days in hospital and extra hours of surgery) may be more reliable measures of the negative effects of surgery

Introduction. Undersizing of an uncemented femoral stem is a post-operative description of a radiograph with unclear clinical importance. It may not always translate into a suboptimal clinical outcome. Aim. To describe a novel classification system of undersizing in a fully hydroxyapatite coated femoral implant, assess if it could be reliably reported between observers, and describe a simple way to assess the degree of undersizing on an AP radiograph. Methods. A retrospective review of 1000 consecutive total hip arthroplasties was conducted. Two investigators reviewed post-operative radiographs independently for stem undersizing. The data was tested for inter and intra-observer agreement using the Kappa method. Results. Undersizing was classified as:. Varus - Stem in contact proximally with medial calcar, and distally with lateral cortex. Valgus - Stem in contact proximally with lateral cortex, and distally with medial cortex. Uniform - Continuous margin around the stem of at least one-half tip width of the stem throughout. Champagne flute - Distal stem fills the narrow diaphysis with insufficient bony contact at the wide metaphysis. If varus or valgus undersizing was present we described the formation of two triangles of excess cancellous space around the implant, each having overlapping apices signifying undersizing by at least two sizes. 32% of the stems were undersized with Kappa demonstrating very good (89%) to good (86%) inter and intra observer agreement respectively. 50% of undersized stems were uniformly undersized, 36% were varus, 6% valgus, and 8% were in a champagne fluted shaped femur. A higher percentage of the lateralised (KLA) stems were undersized compared to other neck configurations (40%). 54% of these were varus undersized and this increased the offset up to 2cm. Conclusion. We describe a classification system for undersizing in hip arthroplasty. KLA stems have an increased tendency to be undersized in varus, thereby increasing the overall offset

There is currently no standardised complication grading classification routinely used for paediatric orthopaedic surgical procedures. The Clavien-Dindo classification used in general surgery was modified and validated in 2011 by Sink et al. and has been used regularly to classify complications following hip preservation surgery. The aim of this study was to adapt and validate Sink et al.'s modification of the Clavien-Dindo classification system for grading complications following surgical interventions of the upper and lower extremities and spine in paediatric orthopaedic patients. Sink et al.'s modification of the Clavien-Dindo classification system was further modified for paediatric orthopaedic procedures. The modified grading scheme was based on the treatment required to treat the complication and the long term morbidity of the complication. Grade I complications do not require deviation from standard treatment. Grade II complications deviate from the normal post-operative course and require outpatient treatment. Grade III complications require investigations, re-admission or re-operation. Grade IV complications are limb or life threatening or have a potential for permanent disability (IVa: with no long term disability and IVb: with long-term disability). Grade V complications result in death. Forty-five complication scenarios were developed. Seven paediatric orthopaedic surgeons were trained to use the modified system and they each graded the scenarios on two occasions. The scenarios were presented in a different random order each time they were graded. Fleiss' and Cohen's k statistics were performed to test for inter-rater and intra-rater reliabilities, respectively. The overall Fleiss' k value for inter-rater reliability was 0.772 (95% CI, 0.744–0.799). The weighted k was 0.765 (95% CI, 0.703–0.826) for Grade I, 0.692 (95% CI, 0.630–0.753) for Grade II, 0.733 (95% CI, 0.671–0.795) for Grade III, 0.657(95% CI, 0.595–0.719) for Grade IVa, 0.769 (95% CI, 0.707–0.83) for Grade IVb and 1.000 for Grade V (p value <0.001). The Cohen's k value for intra-rater reliability was 0.918 (95% CI, 0.887–0.947). These tests show that the adapted classification system has high inter- and intra-rater reliabilities for grading complications following paediatric orthopaedic surgery. Given the high intra- and inter-rater reliability and simplicity of this system, adoption of this grading scheme as a standard of reporting complications in paediatric orthopaedic surgery could be considered. Since the evaluation of surgical outcomes should include the ability to reliably grade surgical complications, this reproducible, reliable system to assess paediatric surgical complications will be a valuable tool for improving surgical practices and patient outcomes

Aims. To evaluate interobserver reliability of the Orthopaedic Trauma Association’s open fracture classification system (OTA-OFC). Patients and Methods. Patients of any age with a first presentation of an open long bone fracture were included. Standard radiographs, wound photographs, and a short clinical description were given to eight orthopaedic surgeons, who independently evaluated the injury using both the Gustilo and Anderson (GA) and OTA-OFC classifications. The responses were compared for variability using Cohen’s kappa. Results. The overall interobserver agreement was ĸ = 0.44 for the GA classification and ĸ = 0.49 for OTA-OFC, which reflects moderate agreement (0.41 to 0.60) for both classifications. The agreement in the five categories of OTA-OFC was: for skin, ĸ = 0.55 (moderate); for muscle, ĸ = 0.44 (moderate); for arterial injury, ĸ = 0.74 (substantial); for contamination, ĸ = 0.35 (fair); and for bone loss, ĸ = 0.41 (moderate). Conclusion. Although the OTA-OFC, with similar interobserver agreement to GA, offers a more detailed description of open fractures, further development may be needed to make it a reliable and robust tool. Cite this article: Bone Joint J 2018;100-B:242–6

Introduction. Automated identification of arthroplasty implants could aid in pre-operative planning and is a task which could be facilitated through artificial intelligence (AI) and deep learning. The purpose of this study was to develop and test the performance of a deep learning system (DLS) for automated identification and classification of knee arthroplasty (KA) on radiographs. Methods. We collected 237 AP knee radiographs with equal proportions of native knees, total KA (TKA), and unicompartmental KA (UKA), as well as 274 radiographs with equal proportions of Smith & Nephew Journey and Zimmer NexGen TKAs. Data augmentation was used to increase the number of images available for DLS development. These images were used to train, validate, and test deep convolutional neural networks (DCNN) to 1) detect the presence of TKA; 2) differentiate between TKA and UKA; and 3) differentiate between the 2 TKA models. Receiver operating characteristic (ROC) curves were generated with area under the curve (AUC) calculated to assess test performance. Results. The DCNNs trained to detect KA and to distinguish between TKA and UKA both achieved AUC of 1. In both cases, heatmap analysis demonstrated appropriate emphasis of the KA components in decision-making. The DCNN trained to distinguish between the 2 TKA models also achieved AUC of 1. Heatmap analysis of this DCNN showed emphasis of specific unique features of the TKA model designs for decision making, such as the anterior flange shape of the Zimmer NexGen TKA (Figure 1) and the tibial baseplate/stem shape of the Smith & Nephew Journey TKA (Figure 2). Conclusion. DCNNs can accurately identify presence of TKA and distinguish between specific designs. The proof-of-concept of these DCNNs may set the foundation for DCNNs to identify other prosthesis models and prosthesis-related complications. For any figures or tables, please contact the authors directly

Aim. Our aim was to compare the Wilkins'-modified Gartland classification and AO classifications of supracondylar humeral fracture with respect to: -Inter-observer reliability; Association of fracture-grade with radiological quality of reduction; Association of fracture-grade with complications. Methods. The unit database was interrogated to identify all operated supracondylar fractures between 2007–2011. Radiographs from each case were evaluated by four observers (three consultants, one trainee) and classified according to Gartland and the AO system. Inter-observer reliability was calculated using Cohen's Kappa coefficient. Radiological quality of reduction was evaluated using a new scoring system, combining the anterior humeral line, the lateral capitello-humeral angle (LCHA) and Baumann's angle, (compared to reference values). Analysis of variance (ANOVA) was performed to determine whether there was a statistically significant difference in scores between the fracture grades. Case notes were reviewed for pre- and post-operative complication, and chi-squared test performed to compare the incidence between different fracture grades. Results. 83 cases were identified for fracture classification and 66 for assessment of reduction and complications. Inter-observer reliability was 0.58 for Gartland (moderate agreement), and 0.70 for the AO classification (good agreement). ANOVA demonstrated no significant difference in the overall reduction scores between the different grades of either classification. Mean scores for LCHA were lower for Gartland-2b (p=0.02) and AO-3 (p=0.007) groups (compared to Gartland-3 and AO-4). Complications were more frequent with the higher grades of fracture in both classifications (p<0.05). Conclusion. The AO classification has greater reliability and should be considered as an alternative to the Gartland classification. A higher grade of fracture is not associated with inferior radiographic outcomes. Surgeons should be aware that restoration of the LCHA is more difficult with the Gartland-2b and AO-3 fractures, probably because of the intact posterior cortex. A greater rate of complications should be expected with higher grades of fracture

Introduction. The use of short stems has been growing in THA for the past five years. As a result, a large number of short stem designs are available in the market place. However, fixation points differ for many of the designs resulting in different radiographic modeling creating confusion when trying to collate to clinical findings. We have created a classification system in an attempted to provide clarity in analyzing radiographic and clinical findings. Method. Femoral implants described as “short stems” were evaluated. The range of lengths for stem type and the method of achieving initial implant stability was determined. The optimal radiographic position of each of these implants and type of bone remodeling associated with this placement was evaluated. Stems were defined as “short” if the tip reached or was proximal to the metaphyseal-diaphyseal junction. This location on the proximal femur was defined as the place at which the medial-lateral metaphyseal flare became parallel. Stems were then classified as: 1.) Metaphyseal Stabilized; 2.) Neck Stabilized; 3.) Head Stabilized. An analysis of radiographic with a minimum of one year follow up were reviewed and posted as to the classification system. Results. The range of stem lengths for stem type and the method of achieving initial implant stability was determined. A classification of short-stemmed components has been defined, making it possible to evaluate and differentiate both radiographic and clinical findings. Not all so-called short stems exhibit the same radiographic and clinical findings. It also became apparent that the different stabilization points require specific surgical techniques to ensure reproducible good results. Findings for neck stabilized present with different findings as compared to metaphyseal stabilized and head stabilized. We are optimistic that this classification system will help to compare short-stemmed implants and how they performed to the more traditional convention cementless stems

Purpose of the study. We propose a simple classification for adolescent idiopathic scoliosis (AIS) based on two components which include the curve type and shoulder level and suggest a treatment algorithm for AIS. Introduction. Few Classification systems for adolescent idiopathic scoliosis (AIS) have helped in communicating, understanding and selecting a treatment for this condition; however, most of these classifications are complex and include many subtypes, making it difficult for the orthopaedic surgeon to use them in clinical practice. The variable reliability and reproducibility of these studies make recommendations and comparisons between various operative treatments a difficult task. Furthermore, none of these classifications has taken the shoulder imbalance into account, despite its importance as a clinical parameter and outcome measure. Methods. We developed a classification system with two components: curve type (I through III) and shoulder level (A or B). The curve types are divided into type I: Primary lumbar-thoracolumbar +/− secondary dorsal; type II: Primary dorsal secondary lumbar and type III: Dorsal. Each curve pattern is subdivided into type A or B depending on the shoulder level. In type A, the lower shoulder is ipsilateral to the concavity of the primary curve. In type B, the shoulders are level or the lower shoulder is on the convexity of the primary curve. This classification was tested for interobserver reliability and intraobserver reproducibility by six surgeons using radiographs of 28 patients. We performed a retrospective analysis of the radiographs of 232 consecutive AIS cases to assess the prevalence of curve types and tested the surgical treatment against the proposed treatment algorithm. Results. Three major types and six subtypes were identified, of which type I accounted for 30%, type II 28% and type III 42%. The kappa coefficient for interobserver reliability was 0.943, while the kappa value for intraobserver reproducibility was 0.964. There was a complete concordance with the shoulder level component. Of the 232 cases reviewed, with a minimum two-year follow-up, only three patients developed a decompensation distal to the instrumentation requiring fusion extension. Conclusion. This classification is the first of its kind to specifically address shoulder imbalance in the surgical decision-making process. The high interobserver reliability and intraobserver reproducibility is due in part to the simplicity of this classification, which makes it an invaluable tool to describe scoliosis curves and offers a potential treatment algorithm in correcting scoliosis

Introduction. The Vancouver Classification System presents a systematic approach to classification of periprosthetic fractures of the proximal femur (PFPFs) that has been validated in previous studies. However, with the introduction of tapered fluted stems and cable plates since the introduction of the Vancouver System, the connection between fracture class and the preferred method of treatment is often unclear. The present study was undertaken to identify fracture patterns surrounding contemporary femoral stems and the relationship between the current method of treatment and the Vancouver Class of the periprosthetic fracture. Methods. Three experienced joint surgeons collected plain radiographs (AP and lateral) and CT/MR scans (n=40) from 72 cases of Vancouver A or B periprosthetic fractures performed over the period 2016–2018. We identified the mode of primary stem fixation and the Vancouver grade of the fracture (A, B1, B2 or B3). Two independent investigators examined all imaging studies and the intraoperative records and recorded: (i) and the location and distribution of the fracture surfaces, and (ii) the presence of incomplete cortical fractures that had initiated within the femoral cortex without completing propagation and (iii) the method of operative treatment. These data were analyzed to examine the incidence of fractures within more than one femoral zone and differences in the fracture patterns corresponding to each Vancouver class. Results. One fifth (21%) of fractures were Type A with the remainder consisting predominantly of Type B2 (39%), with approximately equal proportions of Type B1 (22%) and B3 (18%) fractures. In almost half of Type B2 fractures (a loose femoral stem and a fracture adjacent to the prosthesis), fractures were also present within the metaphysis (ie. Type A+B). In the presence of a cementless femoral stem, fractures often occurred adjacent to the uncoated surface of the stem distal to the proximal ingrowth surface. Type B2 and B3 femurs had similar fracture patterns and degrees of comminution, though their method of treatment differed significantly. Incomplete fractures were identified in every Vancouver class (entire sample: 22%), especially in association with loose stems in poor quality bone (Type B3; 38% of cases). Conclusions. Approximately two-thirds of periprosthetic femoral fractures involve a loose femoral component (ie Types B2 and B3), though bone quality impacts operative treatment. In cementless stems, Vancouver Type B fractures often occur in the unbonded diaphysis between the distal edge of the ingrowth surface and immediately below the stem tip. Incomplete fractures are present in a surprising proportion of cases, suggesting that careful examination of imaging studies is needed to prevent fracture propagation due to inadequate fixation. CT scans are a useful adjunct to supplement plain radiographs. For any tables or figures, please contact the authors directly

The Vancouver classification has been shown by its developers to be a valid and reliable method for categorising the configuration of periprosthetic proximal femoral fractures and for planning their management. We have re-validated this classification system independently using the radiographs of 30 patients with periprosthetic fractures. These were reviewed by six experienced consultant orthopaedic surgeons, six trainee surgeons and six medical students in order to assess intra- and interobserver reliability and reproducibility. Each observer read the radiographs on two separate occasions. The results were subjected to weighted kappa statistical analysis. The respective kappa values for interobserver agreement were 0.72 and 0.74 for consultants, 0.68 and 0.70 for trainees on the first and second readings of the radiographs and 0.61 for medical students. The intra-observer agreement for the consultants was 0.64 and 0.67, for the trainees 0.61 and 0.64, and for the medical students 0.59 and 0.60 for the first and second readings, respectively. The validity of the classification was studied by comparing the pre-operative radiological findings within B subgroups with the operative findings. This revealed agreement for 77% of these type-B fractures, with a kappa value of 0.67. Our data confirm the reliability and reproducibility of this classification system in a European setting and for inexperienced staff. This is a reliable system which can be used by non-experts, between centres and across continents

The authors added a classification of posterior pillars to Herring’s classification of lateral pillars in a retrospective study of 33 patients with Perthes disease. Anteroposterior and frog position lateral radiographs taken approximately two months later from first visit, were evaluated. All patients were treated by a non-weight-bearing method (continuous traction and wheel chair activity). The outcome was evaluated by the Stulberg method. The mean age at follow-up was 18 years (range,14.2 to 26.9 years). Thirteen hips were in Catterall group II, 18 were in group III, and two were in group IV. Twenty-five of the 33 hips were in Stulberg class I or II (with good results), and eight hips were class III. Nine hips were in Herring group A, 20 hips were in group B, and four were in group C. Eleven hips were in our group A with the posterior pillar classification, 16 were in group B, and six were in group C. Group A, with a lateral or posterior pillar had good results without exception. Concerning Herring’s classification, all four heads had become aspherical in group C, however, 16 hips were good results and four hips were poor in group B. The outcome was poorly related to the classification in 20 patients with 20 affected hips in Herring group B when only lateral pillars were used in classification. When both lateral and posterior pillars are considered in classification, results can be predicted more accurately than when only lateral pillars are considered. This more accurate prognosis at an early stage of Perthes disease can facilitate effective treatment selection