This study aimed to develop and validate a fully automated system that quantifies proximal femoral bone mineral density (BMD) from CT images. The study analyzed 978 pairs of hip CT and dual-energy X-ray absorptiometry (DXA) measurements of the proximal femur (DXA-BMD) collected from three institutions. From the CT images, the femur and a calibration phantom were automatically segmented using previously trained deep-learning models. The Hounsfield units of each voxel were converted into density (mg/cm3). Then, a deep-learning model trained by manual landmark selection of 315 cases was developed to select the landmarks at the proximal femur to rotate the CT volume to the neutral position. Finally, the CT volume of the femur was projected onto the coronal plane, and the areal BMD of the proximal femur (CT-aBMD) was quantified. CT-aBMD correlated to DXA-BMD, and a receiver operating characteristic (ROC) analysis quantified the accuracy in diagnosing osteoporosis.Aims
Methods
Aims. The aim of this study was to develop and evaluate machine-learning-based computerized adaptive tests (CATs) for the Oxford Hip Score (OHS), Oxford Knee Score (OKS), Oxford Shoulder Score (OSS), and the Oxford Elbow Score (OES) and its subscales. Methods. We developed CAT algorithms for the OHS, OKS, OSS, overall OES, and each of the OES subscales, using responses to the full-length questionnaires and a machine-learning technique called regression tree learning. The algorithms were evaluated through a series of simulation studies, in which they aimed to predict respondents’ full-length questionnaire scores from only a selection of their item responses. In each case, the total number of items used by the CAT algorithm was recorded and CAT scores were compared to full-length questionnaire scores by mean, SD, score distribution plots, Pearson’s
Aims. Reimers migration percentage (MP) is a key measure to inform decision-making around the management of hip displacement in cerebral palsy (CP). The aim of this study is to assess validity and inter- and intra-rater reliability of a novel method of measuring MP using a smart phone app (HipScreen (HS) app). Methods. A total of 20 pelvis radiographs (40 hips) were used to measure MP by using the HS app. Measurements were performed by five different members of the multidisciplinary team, with varying levels of expertise in MP measurement. The same measurements were repeated two weeks later. A senior orthopaedic surgeon measured the MP on picture archiving and communication system (PACS) as the gold standard and repeated the measurements using HS app. Pearson’s
Aims. The aim of the study was to determine if there was a direct correlation between the pain and disability experienced by patients and size of their disc prolapse, measured by the disc’s cross-sectional area on T2 axial MRI scans. Methods. Patients were asked to prospectively complete visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores on the day of their MRI scan. All patients with primary disc herniation were included. Exclusion criteria included recurrent disc herniation, cauda equina syndrome, or any other associated spinal pathology. T2 weighted MRI scans were reviewed on picture archiving and communications software. The T2 axial image showing the disc protrusion with the largest cross sectional area was used for measurements. The area of the disc and canal were measured at this level. The size of the disc was measured as a percentage of the cross-sectional area of the spinal canal on the chosen image. The VAS leg pain and ODI scores were each correlated with the size of the disc using the Pearson
Aims. The aim of this study was to compare patient-reported outcome measures (PROMs) and the Single Assessment Numerical Evaluation (SANE) score in patients treated with a volar locking plate for a distal radial fracture. Methods. This study was a retrospective review of a prospective database of 155 patients who underwent internal fixation with a volar locking plate for a distal radial fracture between August 2014 and April 2017. Data which were collected included postoperative PROMs (Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) and Patient-Rated Wrist Evaluation (PRWE)), and SANE scores at one month (n = 153), two months (n = 155), three months (n = 144), six months (n = 128), and one year (n = 73) after operation. Patients with incomplete data were excluded from this study. Correlation and agreement between PROMs and SANE scores were evaluated. Subgroup analyses were carried out to identify correlations according to variables such as age, the length of follow-up, and subcategories of the PRWE score. Results. The Pearson
Aims. Assessment of bone mineral density (BMD) with dual-energy X-ray absorptiometry (DXA) is a well-established clinical technique, but it is not available in the acute trauma setting. Thus, it cannot provide a preoperative estimation of BMD to help guide the technique of fracture fixation. Alternative methods that have been suggested for assessing BMD include: 1) cortical measures, such as cortical ratios and combined cortical scores; and 2) aluminium grading systems from preoperative digital radiographs. However, limited research has been performed in this area to validate the different methods. The aim of this study was to investigate the evaluation of BMD from digital radiographs by comparing various methods against DXA scanning. Methods. A total of 54 patients with distal radial fractures were included in the study. Each underwent posteroanterior (PA) and lateral radiographs of the injured wrist with an aluminium step wedge. Overall 27 patients underwent routine DXA scanning of the hip and lumbar spine, with 13 undergoing additional DXA scanning of the uninjured forearm. Analysis of radiographs was performed on ImageJ and Matlab with calculations of cortical measures, cortical indices, combined cortical scores, and aluminium equivalent grading. Results. Cortical measures showed varying correlations with the forearm DXA results (range: Pearson
Aims. This study aims to answer the following questions in patients with hip osteoarthritis (OA) who underwent total hip arthroplasty (THA): are patient-reported outcome measures (PROMs) affected by the location of the maximum severity of pain?; are PROMs affected by the presence of non-groin pain?; are PROMs affected by the severity of pain?; and are PROMs affected by the number of pain locations?. Methods. We reviewed 336 hips (305 patients) treated with THA for hip OA from December 2016 to November 2019 using pain location/severity questionnaires, modified Harris Hip Score (mHHS), Hip Outcome Score (HOS), international Hip Outcome Tool (iHOT-12) score, and radiological analysis. Descriptive statistics, analysis of covariance (ANCOVA), and Spearman partial
Aims. We aimed to assess the reliability and validity of OpenPose, a posture estimation algorithm, for measurement of knee range of motion after total knee arthroplasty (TKA), in comparison to radiography and goniometry. Methods. In this prospective observational study, we analyzed 35 primary TKAs (24 patients) for knee osteoarthritis. We measured the knee angles in flexion and extension using OpenPose, radiography, and goniometry. We assessed the test-retest reliability of each method using intraclass correlation coefficient (1,1). We evaluated the ability to estimate other measurement values from the OpenPose value using linear regression analysis. We used intraclass correlation coefficients (2,1) and Bland–Altman analyses to evaluate the agreement and error between radiography and the other measurements. Results. OpenPose had excellent test-retest reliability (intraclass
Aims. Accurate identification of the ankle joint centre is critical for estimating tibial coronal alignment in total knee arthroplasty (TKA). The purpose of the current study was to leverage artificial intelligence (AI) to determine the accuracy and effect of using different radiological anatomical landmarks to quantify mechanical alignment in relation to a traditionally defined radiological ankle centre. Methods. Patients with full-limb radiographs from the Osteoarthritis Initiative were included. A sub-cohort of 250 radiographs were annotated for landmarks relevant to knee alignment and used to train a deep learning (U-Net) workflow for angle calculation on the entire database. The radiological ankle centre was defined as the midpoint of the superior talus edge/tibial plafond. Knee alignment (hip-knee-ankle angle) was compared against 1) midpoint of the most prominent malleoli points, 2) midpoint of the soft-tissue overlying malleoli, and 3) midpoint of the soft-tissue sulcus above the malleoli. Results. A total of 932 bilateral full-limb radiographs (1,864 knees) were measured at a rate of 20.63 seconds/image. The knee alignment using the radiological ankle centre was accurate against ground truth radiologist measurements (inter-class
Aims. This study investigates the use of the metabolic equivalent of task (MET) score in a young hip arthroplasty population, and its ability to capture additional benefit beyond the ceiling effect of conventional patient-reported outcome measures. Methods. From our electronic database of 751 hip arthroplasty procedures, 221 patients were included. Patients were excluded if they had revision surgery, an alternative hip procedure, or incomplete data either preoperatively or at one-year follow-up. Included patients had a mean age of 59.4 years (SD 11.3) and 54.3% were male, incorporating 117 primary total hip and 104 hip resurfacing arthroplasty operations. Oxford Hip Score (OHS), EuroQol five-dimension questionnaire (EQ-5D), and the MET were recorded preoperatively and at one-year follow-up. The distribution was examined reporting the presence of ceiling and floor effects. Validity was assessed correlating the MET with the other scores using Spearman’s rank
Aims. The distal radius is a major site of osteoporotic bone loss resulting in a high risk of fragility fracture. This study evaluated the capability of a cortical index (CI) at the distal radius to predict the local bone mineral density (BMD). Methods. A total of 54 human cadaver forearms (ten singles, 22 pairs) (19 to 90 years) were systematically assessed by clinical radiograph (XR), dual-energy X-ray absorptiometry (DXA), CT, as well as high-resolution peripheral quantitative CT (HR-pQCT). Cortical bone thickness (CBT) of the distal radius was measured on XR and CT scans, and two cortical indices mean average (CBTavg) and gauge (CBTg) were determined. These cortical indices were compared to the BMD of the distal radius determined by DXA (areal BMD (aBMD)) and HR-pQCT (volumetric BMD (vBMD)). Pearson
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
Aims. The aim of this study was to determine the prevalence and characteristics of C-reactive protein (CRP)-negative prosthetic joint infection (PJI) and evaluate the influence of the type of infecting organism on the CRP level. Patients and Methods. A retrospective analysis of all PJIs affecting the hip or knee that were diagnosed in our institution between March 2013 and December 2016 was performed. A total of 215 patients were included. Their mean age was 71 years (. sd. 11) and there were 118 women (55%). The median serum CRP levels were calculated for various species of organism and for patients with acute postoperative, acute haematogenous, and chronic infections. These were compared using the Kruskal–Wallis test, adjusting for multiple comparisons with Dunn’s test. The correlation between the number of positive cultures and serum CRP levels was estimated using Spearman
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
Aims. To identify a core outcome set of postoperative radiographic measurements to assess technical skill in ankle fracture open reduction internal fixation (ORIF), and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. An e-Delphi exercise was undertaken at a major trauma centre (n = 39) to identify relevant parameters. Feasibility was tested by two authors. Reliability and validity was tested using postoperative radiographs of ankle fracture operations performed by trainees enrolled in an educational trial (IRCTN 20431944). To determine construct validity, trainees were divided into novice (performed < ten cases at baseline) and intermediate groups (performed ≥ ten cases at baseline). To assess concurrent validity, the procedure-based assessment (PBA) was considered the gold standard. The inter-rater and intrarater reliability was tested using a randomly selected subset of 25 cases. Results. Overall, 235 ankle ORIFs were performed by 24 postgraduate year three to five trainees during ten months at nine NHS hospitals in England, UK. Overall, 42 PBAs were completed. The e-Delphi panel identified five ‘final product analysis’ parameters and defined acceptability thresholds: medial clear space (MCS); medial malleolar displacement (MMD); lateral malleolar displacement (LMD); tibiofibular clear space (TFCS) (all in mm); and talocrural angle (TCA) in degrees. Face validity, content validity, and feasibility were excellent. PBA global rating scale scores in this population showed excellent construct validity as continuous (p < 0.001) and categorical (p = 0.001) variables. Concurrent validity of all metrics was poor against PBA score. Intrarater reliability was substantial for all parameters (intraclass
Aims. Patients who sustain neck of femur fractures are at high risk of malnutrition. Our intention was to assess to what extent malnutrition was associated with worse patient outcomes. Methods. A total of 1,199 patients with femoral neck fractures presented to a large UK teaching hospital over a three-year period. All patients had nutritional assessments performed using the Malnutrition Universal Screening Tool (MUST). Malnutrition risk was compared to mortality, length of hospital stay, and discharge destination using logistic regression. Adjustments were made for covariates to identify whether malnutrition risk independently affected these outcomes. Results. Inpatient mortality was 5.2% (35/678) in the group at low risk of malnutrition, 11.3% (46/408) in the medium-risk group, and 17.7% (20/113) in the high-risk group. Multivariate analysis showed each categorical increase in malnutrition risk independently predicted inpatient mortality with an odds ratio (OR) of 1.59 (95% confidence interval (CI) 1.14 to 2.21; p = 0.006). An increased mortality rate persisted at 120 days post-injury (OR 1.64, 95% CI 1.20 to 2.22; p = 0.002). There was a stepwise increase in the proportion of patients discharged to a residence offering a greater level of supported living. Multivariate analysis produced an OR of 1.34 (95% CI 1.03 to 1.75; p = 0.030) for each category of MUST score. Median length of hospital stay increased with a worse MUST score: 13.9 days (interquartile range (IQR) 8.2 to 23.8) in the low-risk group; 16.6 days (IQR 9.0 to 31.5) in the medium-risk group; and 22.8 days (IQR 10.1 to 41.1) in the high-risk group. Adjustment for covariates revealed a partial
Aims. The purpose of this study was to explore the correlation between femoral torsion and morphology of the distal femoral condyle in patients with trochlear dysplasia and lateral patellar instability. Methods. A total of 90 patients (64 female, 26 male; mean age 22.1 years (SD 7.2)) with lateral patellar dislocation and trochlear dysplasia who were awaiting surgical treatment between January 2015 and June 2019 were retrospectively analyzed. All patients underwent CT scans of the lower limb to assess the femoral torsion and morphology of the distal femur. The femoral torsion at various levels was assessed using the a) femoral anteversion angle (FAA), b) proximal and distal anteversion angle, c) angle of the proximal femoral axis-anatomical epicondylar axis (PFA-AEA), and d) angle of the AEA–posterior condylar line (AEA-PCL). Representative measurements of distal condylar length were taken and parameters using the ratios of the bianterior condyle, biposterior condyle, bicondyle, anterolateral condyle, and anteromedial condyle were calculated and correlated with reference to the AEA, using the Pearson
Aims. We quantitatively compared the 3D bone density distributions on CT scans performed on scaphoid waist fractures subacutely that went on to union or nonunion, and assessed whether 2D CT evaluations correlate with 3D bone density evaluations. Methods. We constructed 3D models from 17 scaphoid waist fracture CTs performed between four to 18 weeks after fracture that did not unite (nonunion group), 17 age-matched scaphoid waist fracture CTs that healed (union group), and 17 age-matched control CTs without injury (control group). We measured the 3D bone density for the distal and proximal fragments relative to the triquetrum bone density and compared findings among the three groups. We then performed bone density measurements using 2D CT and evaluated the correlation with 3D bone densities. We identified the optimal cutoff with diagnostic values of the 2D method to predict nonunion with receiver operating characteristic (ROC) curves. Results. In the nonunion group, both the distal (100.2%) and proximal (126.6%) fragments had a significantly higher bone density compared to the union (distal: 85.7%; proximal: 108.3%) or control groups (distal: 91.6%; proximal: 109.1%) using the 3D bone density measurement, which were statistically significant for all comparisons. 2D measurements were highly correlated to 3D bone density measurements (Spearman’s
Aims. To validate the Sydney Hamstring Origin Rupture Evaluation (SHORE), a hamstring-specific clinical assessment tool to evaluate patient outcomes following surgical treatment. Methods. A prospective study of 70 unilateral hamstring surgical repairs, with a mean age of 47.3 years (15 to 73). Patients completed the SHORE preoperatively and at six months post-surgery, and then completed both the SHORE and Perth Hamstring Assessment Tool (PHAT) at three years post-surgery. The SHORE questionnaire was validated through the evaluation of its psychometric properties, including; internal consistency, reproducibility, reliability, sensitivity to change, and ceiling effect. Construct validity was assessed using Pearson’s correlation analysis to examine the strength of association between the SHORE and the PHAT. Results. The SHORE demonstrated an excellent completion rate (100%), high internal consistency (Cronbach’s alpha 0.78), and good reproducibility (intraclass
In this study we evaluated whether pre-operative
Western Ontario and McMaster Universities (WOMAC) osteoarthritis
scores can predict satisfaction following total hip arthroplasty
(THA). Prospective data for a cohort of patients undergoing THA
from two large academic centres were collected, and pre-operative
and one-year post-operative WOMAC scores and a 25-point satisfaction
questionnaire were obtained for 446 patients. Satisfaction scores
were dichotomised into either improvement or deterioration. Scatter
plots and Spearman’s rank
Aims. To assess the correlation between the histological response to preoperative chemotherapy and event-free survival (EFS) or overall survival (OS) in patients with high-grade localized osteosarcoma. Methods. Out of 625 patients aged ≤ 40 years treated for primary high-grade osteosarcoma between 1997 and 2016, 232 patients without clinically detectable metastases at the time of diagnosis and treated with preoperative high-dose methotrexate, adriamycin and cisplatin (MAP) chemotherapy and surgery were included. Associations of chemotherapy-induced necrosis in the resected specimen and EFS or OS were assessed using Cox model and the Pearson’s
Aims. The optimum clearance between the bearing surfaces of hip arthroplasties is unknown. Theoretically, to minimize wear, it is understood that clearances must be low enough to maintain optimal contact pressure and fluid film lubrication, while being large enough to allow lubricant recovery and reduce contact patch size. This study aimed to identify the relationship between diametrical clearance and volumetric wear, through the analysis of retrieved components. Methods. A total of 81 metal-on-metal Pinnacle hips paired with 12/14 stems were included in this study. Geometrical analysis was performed on each component, using coordinate and roundness measuring machines. The relationship between their as-manufactured diametrical clearance and volumetric wear was investigated. The Mann-Whitney U test and unpaired t-test were used, in addition to calculating the non-parametric Spearman's
Aims. Several radiological methods of measuring anteversion of the acetabular component after total hip arthroplasty (THA) have been described. These are limited by low reproducibility, are less accurate than CT 3D reconstruction, and are cumbersome to use. These methods also partly rely on the identification of obscured radiological borders of the component. We propose two novel methods, the Area and Orthogonal methods, which have been designed to maximize use of readily identifiable points while maintaining the same trigonometric principles. Patients and Methods. A retrospective study of plain radiographs was conducted on 160 hips of 141 patients who had undergone primary THA. We compared the reliability and accuracy of the Area and Orthogonal methods with two of the current leading methods: those of Widmer and Lewinnek, respectively. Results. The 160 anteroposterior pelvis films revealed that the proposed Area method was statistically different from those described by Widmer and Lewinnek (p < 0.001 and p = 0.004, respectively). They gave the highest inter- and intraobserver reliability (0.992 and 0.998, respectively), and took less time (27.50 seconds (. sd. 3.19); p < 0.001) to complete. In addition, 21 available CT 3D reconstructions revealed the Area method achieved the highest Pearson’s
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
Aims. The aim of this study was to assess the effect of posterior cruciate ligament (PCL) resection on flexion-extension gaps, mediolateral soft-tissue laxity, fixed flexion deformity (FFD), and limb alignment during posterior-stabilized (PS) total knee arthroplasty (TKA). Patients and Methods. This prospective study included 110 patients with symptomatic osteoarthritis of the knee undergoing primary robot-assisted PS TKA. All operations were performed by a single surgeon using a standard medial parapatellar approach. Optical motion capture technology with fixed femoral and tibial registration pins was used to assess gaps before and after PCL resection in extension and 90° knee flexion. Measurements were made after excision of the anterior cruciate ligament and prior to bone resection. There were 54 men (49.1%) and 56 women (50.9%) with a mean age of 68 years (. sd. 6.2) at the time of surgery. The mean preoperative hip-knee-ankle deformity was 4.1° varus (. sd. 3.4). Results. PCL resection increased the mean flexion gap significantly more than the extension gap in the medial (2.4 mm (. sd. 1.5) vs 1.3 mm (. sd. 1.0); p < 0.001) and lateral (3.3 mm (. sd. 1.6) vs 1.2 mm (. sd. 0.9); p < 0.01) compartments. The mean gap differences after PCL resection created significant mediolateral laxity in flexion (gap difference: 1.1 mm (. sd. 2.5); p < 0.001) but not in extension (gap difference: 0.1 mm (. sd. 2.1); p = 0.51). PCL resection significantly improved the mean FFD (6.3° (. sd. 4.4) preoperatively vs 3.1° (. sd. 1.5) postoperatively; p < 0.001). There was a strong positive correlation between the preoperative FFD and change in FFD following PCL resection (Pearson’s
Aims. The purpose of this investigation was to determine the relationship between height, weight, and sex with implant size in total knee arthroplasty (TKA) using a multivariate linear regression model and a Bayesian model. Methods. A retrospective review of an institutional registry was performed of primary TKAs performed between January 2005 and December 2016. Patient demographics including patient age, sex, height, weight, and body mass index (BMI) were obtained from registry and medical record review. In total, 8,100 primary TKAs were included. The mean age was 67.3 years (SD 9.5) with a mean BMI of 30.4 kg/m. 2. (SD 6.3). The TKAs were randomly split into a training cohort (n = 4,022) and a testing cohort (n = 4,078). A multivariate linear regression model was created on the training cohort and then applied to the testing cohort . A Bayesian model was created based on the frequencies of implant sizes in the training cohort. The model was then applied to the testing cohort to determine the accuracy of the model at 1%, 5%, and 10% tolerance of inaccuracy. Results. Height had a relatively strong correlation with implant size (femoral component anteroposterior (AP) Pearson
Aims. The aim of this study was to determine if the Oxford Knee and Hip Score (OKHS) can accurately predict when a primary knee or hip referral is deemed nonsurgical versus surgical by the surgeon during their first consultation, and to identify nonsurgical OKHS screening thresholds. Patients and Methods. We retrospectively reviewed pre-consultation OKHS for all consecutive primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) consultations of a single surgeon over three years. The 1436 knees (1016 patients) and 478 hips (388 patients) included were categorized based on the surgeon’s decision into those offered surgery during the first consultation versus those not (nonsurgical). Spearman’s rank
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
Aims. The aims of this study were to investigate any possible relationship
between a preoperative sensitivity to pain and the degree of pain
at rest and on exertion with postoperative function in patients
who underwent stemless total shoulder arthroplasty (TSA). Patients and Methods. In this prospective study, we included 63 patients who underwent
stemless TSA and were available for evaluation one year postoperatively.
There were 31 women and 32 men; their mean age was 71 years (53
to 89). The pain threshold, which was measured using a Pain Matcher
(PM) unit, the degree of pain (visual analogue scale at rest and
on exertion, and function using the short version of the Disabilities
of the Arm, Shoulder and Hand questionnaire (QuickDASH), were recorded
preoperatively, as well as three and 12 months postoperatively. Results. We found an inverse relationship between both the preoperative
PM threshold and pain (VAS) at rest and the 12-month postoperative
QuickDASH score (Pearson
Aims. The purpose of this retrospective study was to investigate the
clinical relevance of increased facet joint distraction as a result
of anterior cervical decompression and fusion (ACDF) for trauma. Patients and Methods. A total of 155 patients (130 men, 25 women. Mean age 42.7 years;
16 to 87) who had undergone ACDF between 1 January 2001 and 1 January
2016 were included in the study. Outcome measures included the Neck
Disability Index (NDI) and visual analogue scale (VAS) for pain.
Lateral cervical spine radiographs taken in the immediate postoperative
period were reviewed to compare the interfacet distance of the operated
segment with those of the facet joints above and below. Results. There was a statistically significant relationship between greater
facet distraction and increased NDI and VAS pain scores. This was
further confirmed by Spearman correlation, which showed evidence
of a moderate correlation between both NDI score and facet joint
distraction (Spearman
Aims. The purpose of this study was to evaluate whether an innovative
templating technique could predict the need for acetabular augmentation
during primary total hip arthroplasty for patients with dysplastic
hips. Patients and Methods. We developed a simple templating technique to estimate acetabular
component coverage at total hip arthroplasty, the True Cup: False
Cup (TC:FC) ratio. We reviewed all patients with dysplastic hips
who underwent primary total hip arthroplasty between 2005 and 2012.
Traditional radiological methods of assessing the degree of acetabular dysplasia
(Sharp’s angle, Tönnis angle, centre-edge angle) as well as the
TC:FC ratio were measured from the pre-operative radiographs. A
comparison of augmented and non-augmented hips was undertaken to
determine any difference in pre-operative radiological indices between
the two cohorts. The intra- and inter-observer reliability for all
radiological indices used in the study were also calculated. Results. Of the 128 cases reviewed, 33 (26%) needed acetabular augmentation.
We found no difference in the median Sharp’s angle (p = 0.10), Tönnis
angle (p = 0.28), or centre-edge angle (p = 0.07) between the two
groups. A lower TC:FC ratio was observed in the augmented group
compared with the non-augmented group (median = 0.66 versus 0.88, p <
0.001).
Intra-observer reliability was found to be high for all radiological
indices analysed (interclass
Objectives. The primary objective of this study was to compare accuracy in restoring the native centre of hip rotation in patients undergoing conventional manual total hip arthroplasty (THA) versus robotic-arm assisted THA. Secondary objectives were to determine differences between these treatment techniques for THA in achieving the planned combined offset, component inclination, component version, and leg-length correction. Materials and Methods. This prospective cohort study included 50 patients undergoing conventional manual THA and 25 patients receiving robotic-arm assisted THA. Patients undergoing conventional manual THA and robotic-arm assisted THA were well matched for age (mean age, 69.4 years (. sd. 5.2) vs 67.5 years (. sd. 5.8) (p = 0.25); body mass index (27.4 kg/m. 2. (. sd. 2.1) vs 26.9 kg/m. 2. (. sd. 2.2); p = 0.39); and laterality of surgery (right = 28, left = 22 vs right = 12, left = 13; p = 0.78). All operative procedures were undertaken by a single surgeon using the posterior approach. Two independent blinded observers recorded all radiological outcomes of interest using plain radiographs. Results. The
Objectives. Whilst gait speed is variable between healthy and injured adults, the extent to which speed alone alters the 3D in vivo knee kinematics has not been fully described. The purpose of this prospective study was to understand better the spatiotemporal and 3D knee kinematic changes induced by slow compared with normal self-selected walking speeds within young healthy adults. Methods. A total of 26 men and 25 women (18 to 35 years old) participated in this study. Participants walked on a treadmill with the KneeKG system at a slow imposed speed (2 km/hr) for three trials, then at a self-selected comfortable walking speed for another three trials. Paired t-tests, Wilcoxon signed-rank tests, Mann-Whitney U tests and Spearman’s rank
Objectives. The purpose of this study was to compare the thickness of the hip capsule in patients with surgical hip disease, either with cam-femoroacetabular impingement (FAI) or non-FAI hip pathology, with that of asymptomatic control hips. Methods. A total of 56 hips in 55 patients underwent a 3Tesla MRI of the hip. These included 40 patients with 41 hips with arthroscopically proven hip disease (16 with cam-FAI; nine men, seven women; mean age 39 years, 22 to 58) and 25 with non-FAI chondrolabral pathology (four men, 21 women; mean age 40 years, 18 to 63) as well as 15 asymptomatic volunteers, whose hips served as controls (ten men, five women; mean age 62 years, 33 to 77). The maximal capsule thickness was measured anteriorly and superiorly, and compared within and between the three groups with a gender subanalysis using student’s t-test. The correlation between alpha angle and capsule thickness was determined using Pearson’s
Objectives. The determination of the volumetric polyethylene wear on explanted material requires complicated equipment, which is not available in many research institutions. Our aim in this study was to present and validate a method that only requires a set of polyetheretherketone balls and a laboratory balance to determine wear. Methods. The insert to be measured was placed on a balance, and a ball of the appropriate diameter was inserted. The cavity remaining between the ball and insert caused by wear was filled with contrast medium and the weight of the contrast medium was recorded. The volume was calculated from the known density of the liquid. The precision, inter- and intraobserver reliability, were determined by four investigators on four days using nine inserts with specified wear (0.094 ml to 1.626 ml), and the intra-class
Locognosia, the ability to localise touch, is one aspect of tactile spatial discrimination which relies on the integrity of peripheral end-organs as well as the somatosensory representation of the surface of the body in the brain. The test presented here is a standardised assessment which uses a protocol for testing locognosia in the zones of the hand supplied by the median and/or ulnar nerves. The test-retest reliability and discriminant validity were investigated in 39 patients with injuries to the median or ulnar nerve. Intraclass correlation coefficients were used to calculate the test-retest reliability. Discriminant validity was assessed by comparing the injured with the unaffected hand. Excellent test-retest reliability was demonstrated for the injuries to the median (intraclass
Stereoradiography with a base shift of the source of illumination was used to produce pairs of radiographs to be measured by stereophotogrammetric techniques. The direction of shift was parallel with the longitudinal axis of the body, so that each radiograph in the stereopair could be used for other clinical purposes. A base shift of 10 centimetres with a distance of 100 centimetres between the focus and the film gave acceptable value of stereoscopic parallax. The radiographs were measured using a Hilger and Watts medical stereometer. This method was checked with test specimens, namely an osteotomised pelvis in which one acetabulum could be rotated and an osteotomised femur in which the whole upper portion could be rotated against the shaft. Measurements made on the acetabulum and its radiographs showed a
We have developed a novel method of calculating the radiological magnification of the hip using two separate radio-opaque markers. We recruited 74 patients undergoing radiological assessment following total hip replacement. Both the new double marker and a conventional single marker were used by the radiographer at the time of x-ray. The predicted magnification according to each marker was calculated, as was the true radiological magnification of the components. The correlation between true and predicted magnification was good using the double marker (r = 0.90, n = 74, p <
0.001), but only moderate for the single marker (r = 0.50, n = 63, p <
0.001). The median error was significantly less for the double marker than for the single (1.1% vs 4.8%, p <
0.001). The double marker method demonstrated excellent validity (intraclass
This study validates the short-form WOMAC function scale for assessment of conservative treatment of osteoarthritis of the knee. Data were collected before treatment and six and nine months later, from 100 patients with osteoarthritis of the knee to determine the validity, internal consistency, test-retest reliability, floor and ceiling effects, and responsiveness of the short-form WOMAC function scale. The scale showed high correlation with the traditional WOMAC and other measures. The internal consistency was good (Cronbach α: 0.88 to 0.95) and an excellent test-retest reliability was found (Lin’s concordance
This study examined the role of vitamin D as a factor accounting for fatty degeneration and muscle function in the rotator cuff. There were 366 patients with disorders of the shoulder. A total of 228 patients had a full-thickness tear (group 1) and 138 patients had no tear (group 2). All underwent magnetic resonance arthrography and an isokinetic muscle performance test. The serum concentrations of vitamin D (25(OH)D. 3. ) were measured. In general, a lower serum level of vitamin D was related to higher fatty degeneration in the muscles of the cuff. Spearman’s
We evaluated the construct validity of the Musculoskeletal Tumour Society rating scale (Enneking score) as a functional measure for patients with sarcoma involving the upper limb. We compared the Enneking score by examining the correlation between two patient-derived outcome measures, the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and the Medical Outcomes Study Short Form-36 (SF-36) as indicators of functional status in 40 patients with malignant or aggressive benign bone and soft-tissue tumours of the upper limb who had undergone surgical treatment. The frequency distributions were similar among the three scoring systems. As for the validity, Spearman’s rank
Proximal femoral varus osteotomy improves the
biomechanics of the hip and can stimulate normal acetabular development
in a dysplastic hip. Medial closing wedge osteotomy remains the
most popular technique, but is associated with shortening of the
ipsilateral femur. We produced a trigonometric formula which may be used pre-operatively
to predict the resultant leg length discrepancy (LLD). We retrospectively
examined the influence of the choice of angle in a closing wedge
femoral osteotomy on LLD in 120 patients (135 osteotomies, 53% male,
mean age six years, (3 to 21), 96% caucasian) over a 15-year period
(1998 to 2013). A total of 16 of these patients were excluded due
to under or over varus correction. The patients were divided into
three age groups: paediatric (<
10 years), adolescent (10 to
16 years) and adult (>
16 years). When using the same saw blades
as in this series, the results indicated that for each 10° of angle
of resection the resultant LLD equates approximately to multiples
of 4 mm, 8 mm and 12 mm in the three age groups, respectively. Statistical testing of the 59 patients who had a complete set
of pre- and post-operative standing long leg radiographs, revealed
a Pearson’s
We report the effect of padding on the efficiency of the pneumatic tourniquet for the upper limb. Varying thicknesses of two commercially-available types of orthopaedic padding (Cellona and Velband) were applied to the arms of 20 volunteers, with three pressure transducers placed directly beneath the padding. A tourniquet was positioned over the padding and inflated to 220 mmHg. Significant reductions in the transmitted pressure were recorded from the transducers with both padding materials. With eight layers of padding, reductions in pressure of 13% (1% to 26%) and 18% (7% to 35%) were seen with Cellona and Velband, respectively. The reduction in pressure with Velband padding correlated with increasing arm circumference (Pearson’s
In a prospective study, 232 neonates were examined sonographically using the methods of Graf and Terjesen. In order to determine the reproducibility of the methods, 50 hips were evaluated by two skilled examiners. In an inter-observer study, five physicians and five medical students evaluated 24 images, which were evaluated on ten occasions at two-weekly intervals by one of the authors. Statistical evaluation used the Bland-Altman approach. The neonates (110 females, 122 males) were less than four days old. The mean α angle was 62.4° and mean femoral head cover was 55.4%. According to Graf’s method, 1.3% of hips were pathological, compared with 4.1% according to Terjesen. Spearman’s
Aims. Accurate placement of the acetabular component is essential in
total hip arthroplasty (THA). The purpose of this study was to determine
if the ability to achieve inclination of the acetabular component
within the ‘safe-zone’ of 30° to 50° could be improved with the
use of an inclinometer. Patients and Methods. We reviewed 167 primary THAs performed by a single surgeon over
a period of 14 months. Procedures were performed at two institutions:
an inpatient hospital, where an inclinometer was used (inclinometer
group); and an ambulatory centre, where an inclinometer was not
used as it could not be adequately sterilized (control group). We excluded
47 patients with a body mass index (BMI) of > 40 kg/m. 2. ,
age of > 68 years, or a surgical indication other than osteoarthritis
whose treatment could not be undertaken in the ambulatory centre.
There were thus 120 patients in the study, 68 in the inclinometer
group and 52 in the control group. The inclination angles of the acetabular
component were measured from de-identified plain radiographs by
two blinded investigators who were not involved in the surgery.
The effect of the use of the inclinometer on the inclination angle
was determined using multivariate regression analysis. Results. The mean inclination angle for the THAs in the inclinometer group
was 42.9° (95% confidence interval (CI) 41.7° to 44.0°; range 29.0°
to 63.8°) and 46.5° (95% CI 45.2° to 47.7°; range 32.8° to 63.2°)
in the control group (p < 0.001). Regression analysis identified
a 9.1% difference in inclination due to the use of an inclinometer
(p < 0.001), and THAs performed without the inclinometer were
three times more likely to result in inclination angles of > 50°
(odds ratio (OR) 2.8, p = 0.036). The
Femoral stem version has a major influence on
impingement and early post-operative stability after total hip arthroplasty
(THA). The main objective of this study was to evaluate the validity
of a novel radiological method for measuring stem version. Anteroposterior
(AP) radiographs and three-dimensional CT scans were obtained for
115 patients (female/male 63/72, mean age 62.5 years (50 to 75))
who had undergone minimally invasive, cementless THA. Stem version was
calculated from the AP hip radiograph by rotation-based change in
the projected prosthetic neck–shaft (NSA*) angle using the mathematical
formula ST = arcos [tan (NSA*) / tan (135)]. We used two independent
observers who repeated the analysis after a six-week interval. Radiological
measurements were compared with 3D-CT measurements by an independent,
blinded external institute. We found a mean difference of 1.2° (. sd. 6.2) between
radiological and 3D-CT measurements of stem version. The correlation
between the mean radiological and 3D-CT stem torsion was r = 0.88
(p <
0.001). The intra- (intraclass
Objectives. The purpose of this study was to investigate whether the femoral
head–neck contour, characterised by the alpha angle, varies with
the stage of physeal maturation using MRI evaluation of an asymptomatic
paediatric population. . Methods. Paediatric volunteers with asymptomatic hips were recruited to
undergo MRI of both hips. Femoral head physes were graded from 1
(completely open) to 6 (completely fused). The femoral head–neck
contour was evaluated using the alpha angle, measured at the 3:00
(anterior) and 1:30 (anterosuperior) positions and correlated with
physeal grade, with gender sub-analysis performed. Results. A total of 43 asymptomatic paediatric volunteers (26 male, 17
female) with mean age 13.0 years (eight to 18) were included with
review of bilateral hip MRIs. Correlation between the physeal grade
and alpha angle was moderate in males at both the 3:00 (r = 0.477,
p <
0.001) and 1:30 (r = 0.509, p <
0.001) positions, whereas
there was no significant correlation in females. A significant difference
was found between the alpha angles of all the physeal grades (3:00,
p = 0.030, 1:30, p = 0.005), but only in males, with the angle increasing
with higher grades. For physeal grading, the inter-reader reliability
was substantial (intraclass
We have studied the concept of posterior condylar offset and the importance of its restoration on the maximum range of knee flexion after posterior-cruciate-ligament-retaining total knee replacement (TKR). We measured the difference in the posterior condylar offset before and one year after operation in 69 patients who had undergone a primary cruciate-sacrificing mobile bearing TKR by one surgeon using the same implant and a standardised operating technique. In all the patients true pre- and post-operative lateral radiographs had been taken. The mean pre- and post-operative posterior condylar offset was 25.9 mm (21 to 35) and 26.9 mm (21 to 34), respectively. The mean difference in posterior condylar offset was + 1 mm (−6 to +5). The mean pre-operative knee flexion was 111° (62° to 146°) and at one year postoperatively, it was 107° (51° to 137°). There was no statistical correlation between the change in knee flexion and the difference in the posterior condylar offset after TKR (Pearson
The purpose of this study was to identify factors
that predict implant cut-out after cephalomedullary nailing of intertrochanteric
and subtrochanteric hip fractures, and to test the significance
of calcar referenced tip-apex distance (CalTAD) as a predictor for
cut-out. We retrospectively reviewed 170 consecutive fractures that had
undergone cephalomedullary nailing. Of these, 77 met the inclusion
criteria of a non-pathological fracture with a minimum of 80 days
radiological follow-up (mean 408 days; 81 days to 4.9 years). The
overall cut-out rate was 13% (10/77). The significant parameters in the univariate analysis were tip-apex
distance (TAD) (p <
0.001), CalTAD (p = 0.001), cervical angle
difference (p = 0.004), and lag screw placement in the anteroposterior
(AP) view (Parker’s ratio index) (p = 0.003). Non-significant parameters
were age (p = 0.325), gender (p = 1.000), fracture side (p = 0.507),
fracture type (AO classification) (p = 0.381), Singh Osteoporosis
Index (p = 0.575), lag screw placement in the lateral view (p =
0.123), and reduction quality (modified Baumgaertner’s method) (p = 0.575).
In the multivariate analysis, CalTAD was the only significant measurement
(p = 0.001). CalTAD had almost perfect inter-observer reliability
(interclass
Transtrochanteric curved varus osteotomy was designed to avoid some of the disadvantages of varus wedge osteotomy, such as post-operative leg-length discrepancy. In this retrospective study we investigated the leg-length discrepancy and clinical outcome after transtrochanteric curved varus osteotomy undertaken in patients with osteonecrosis of the femoral head. Between January 1993 and March 2004, this osteotomy was performed in 42 hips of 36 patients with osteonecrosis of the femoral head. There were 15 males and 21 females with a mean age at surgery of 34 years (15 to 68). The mean follow-up was 5.9 years (2.0 to 12.5). The mean pre-operative Harris hip score was 64.0 (43 to 85) points, which improved to a mean of 88.7 (58 to 100) points at final follow-up. The mean varus angulation post-operatively was 25° (12° to 38°) and the post-operative mean leg-length discrepancy was 13 mm (4 to 25). The post-operative leg-length discrepancy showed a strong correlation with varus angulation (Pearson’s