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The Bone & Joint Journal
Vol. 102-B, Issue 3 | Pages 388 - 393
1 Mar 2020
French SR Kaila R Munir S Wood DG

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.


The Bone & Joint Journal
Vol. 98-B, Issue 3 | Pages 320 - 325
1 Mar 2016
Gundtoft PH Pedersen AB Schønheyder HC Overgaard S

Aims

The purpose of this study was to validate the diagnosis of periprosthetic joint infection (PJI) in the Danish Hip Arthroplasty Register (DHR).

Patients and Methods

We identified a cohort of patients from the DHR who had undergone primary total hip arthroplasty (THA) since 1 January 2005 and followed them until first-time revision, death, emigration or until 31 December 2012.

Revision for PJI, as registered in the DHR, was validated against a benchmark which included information from microbiology databases, prescription registers, clinical biochemistry registers and clinical records.

We estimated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for PJI in the DHR alone and in the DHR when combined with microbiology databases.


The Bone & Joint Journal
Vol. 99-B, Issue 2 | Pages 218 - 224
1 Feb 2017
Hamilton DF Loth FL Giesinger JM Giesinger K MacDonald DJ Patton JT Simpson AHRW Howie CR

Aims

To validate the English language Forgotten Joint Score-12 (FJS-12) as a tool to evaluate the outcome of hip and knee arthroplasty in a United Kingdom population.

Patients and Methods

All patients undergoing surgery between January and August 2014 were eligible for inclusion. Prospective data were collected from 205 patients undergoing total hip arthroplasty (THA) and 231 patients undergoing total knee arthroplasty (TKA). Outcomes were assessed with the FJS-12 and the Oxford Hip and Knee Scores (OHS, OKS) pre-operatively, then at six and 12 months post-operatively. Internal consistency, convergent validity, effect size, relative validity and ceiling effects were determined.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_5 | Pages 24 - 24
1 Apr 2019
Hettich G Schierjott RA Schilling C Maas A Ramm H Bindernagel M Lamecker H Grupp TM
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Introduction. Acetabular bone defects are still challenging to quantify. Numerous classification schemes have been proposed to categorize the diverse kinds of defects. However, these classification schemes are mainly descriptive and hence it remains difficult to apply them in pre-clinical testing, implant development and pre-operative planning. By reconstructing the native situation of a defect pelvis using a Statistical Shape Model (SSM), a more quantitative analysis of the bone defects could be performed. The aim of this study is to develop such a SSM and to validate its accuracy using relevant clinical scenarios and parameters. Methods. An SSM was built on the basis of segmented 66 CT dataset of the pelvis showing no orthopedic pathology. By adjusting the SSM's so called modes of shape variation it is possible to synthetize new 3D pelvis shapes. By fitting the SSM to intact normal parts of an anatomical structure, missing or pathological regions can be extrapolated plausibly. The validity of the SSM was tested by a Leave-one-out study, whereby one pelvis at a time was removed from the 66 pelvises and was reconstructed using a SSM of the remaining 65 pelvises. The reconstruction accuracy was assessed by comparing each original pelvis with its reconstruction based on the root-mean-square (RMS) surface error and five clinical parameters (center of rotation, acetabulum diameter, inclination, anteversion, and volume). The influence of six different numbers of shape variation modes (reflecting the degrees of freedom of the SSM) and four different mask sizes (reflecting different clinical scenarios) was analyzed. Results. The Leave-one-out study showed that the reconstruction errors decreased when the number of shape variation modes included in the SSM increased from 0 to 20, but remained almost constant for higher numbers of shape variation modes. For the SSM with 20 shape variation modes, the RMS of the reconstruction error increased with increasing mask size, whereas the other parameters only increased from Mask_0 to Mask_1, but remained almost constant for Mask_1, Mask_2 and Mask_3. Median reconstruction errors for Mask_1, Mask_2, and Mask_3 were approximately 3 mm in Center of Rotation (CoR) position, 2 mm in Diameter, 3° in inclination and anteversion, as well as 5 ml in volume. Discussion. This is the first study analyzing and showing the feasibility of a quantitative analysis of acetabular bone defects using a SSM-based reconstruction method in the clinical scenario of a defect or implant in both acetabuli and incomplete CT-scans. Validation results showed acceptable reconstruction accuracy, also for clinical scenarios in which less healthy bone remains. Further studies could apply this method on a larger number of defect pelvises to obtain quantitative measures of acetabular bone defects


Bone & Joint Research
Vol. 6, Issue 6 | Pages 376 - 384
1 Jun 2017
Stentz-Olesen K Nielsen ET De Raedt S Jørgensen PB Sørensen OG Kaptein BL Andersen MS Stilling M

Objectives. Static radiostereometric analysis (RSA) using implanted markers is considered the most accurate system for the evaluation of prosthesis migration. By using CT bone models instead of markers, combined with a dynamic RSA system, a non-invasive measurement of joint movement is enabled. This method is more accurate than current 3D skin marker-based tracking systems. The purpose of this study was to evaluate the accuracy of the CT model method for measuring knee joint kinematics in static and dynamic RSA using the marker method as the benchmark. Methods. Bone models were created from CT scans, and tantalum beads were implanted into the tibia and femur of eight human cadaver knees. Each specimen was secured in a fixture, static and dynamic stereoradiographs were recorded, and the bone models and marker models were fitted to the stereoradiographs. Results. Results showed a mean difference between the two methods in all six degrees of freedom for static RSA to be within -0.10 mm/° and 0.08 mm/° with a 95% limit of agreement (LoA) ranging from ± 0.49 to 1.26. Dynamic RSA had a slightly larger range in mean difference of -0.23 mm/° to 0.16 mm/° with LoA ranging from ± 0.75 to 1.50. Conclusions. In a laboratory-controlled setting, the CT model method combined with dynamic RSA may be an alternative to previous marker-based methods for kinematic analyses. Cite this article: K. Stentz-Olesen, E. T. Nielsen, S. De Raedt, P. B. Jørgensen, O. G. Sørensen, B. L. Kaptein, M. S. Andersen, M. Stilling. Validation of static and dynamic radiostereometric analysis of the knee joint using bone models from CT data. Bone Joint Res 2017;6:376–384. DOI: 10.1302/2046-3758.66.BJR-2016-0113.R3


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 163 - 164
1 Mar 2009
Richter M Zech S Hildebrand F Schulz-Wildelau C Gaulke R Goering K
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PURPOSE: A new device for intraoperative pedography was developed. The purpose of this study was to validate the introduced method with standard dynamic pedography, and to analyze the clinical benefit. Methods: For an intraoperative introduction of standardized forces to the footsole, a device named Kraftsimulator Intraoperative Pedographie was developed. The validation was performed in two steps: Step 1. Comparison of standard dynamic pedography (three trials, walking, third step, three trials, mid stance force pattern), static pedography in standing position (three trials) and pedography with KIOP in healthy volunteers (three trials, total force 400 N).. Step 2. Comparison between pedography in standing position, pedography with KIOP in awake and anaesthesized patients (three trials, total force 400 N). A randomized prospective controlled study comparing treatment with and without intraoperative pedography has started on November 1, 2005. The subjects are randomized into two groups,. a) use of intraoperative pedography, versus. b) no use of intraoperative pedography. One-year-follow-up including standard dynamic pedography is planned. The following scores are used: American Orthopaedic Foot and Ankle Society (AOFAS), Visual-Analogue-Scale Foot and Ankle (VAS FA), Short-Form 36 (SF36, standardized to 100-point-maximum). Intraoperative consequences after the use of intraoperative pedography were recorded. Results: Validation Step 1: 30 individuals were included (age, 26.1±8.6 years; gender, male: female = 24: 6). Step 2: 30 individuals were included (age, 55.3±30.3 years; gender, male: female = 24: 6). No significant differences between all measurements of step 1 and 2 were found for step 1 and 2 without the dynamic platform measurements of step 1. Clinical use: 16 patients were included until January 31, 2006 (ankle correction arthrodesis, n=2; subtalar joint correction arthrodesis, n=4; arthrodesis midfoot, n=4, correction forefoot, 4; Lisfrcan-fracture-dislocation, n=2). 9 patients were randomized for the use of intraoperative pedography. The mean preoperative scores were: AOFAS: 49.6±23.7; VAS FA: 42.2±13.1; SF36: 48.1±23.2. The mean interruption of operative procedure for the intraoperative pedography was 359±34 seconds. In 4/9 cases changes were made after intraoperative pedography during the same operative procedure (correction modified, n=3; screw tightened, n=1). The follow-up has not been completed so far. Conclusion: Since no statistical significant differences were found between the measurements of intraoperative pedography in anaesthesized individuals and the standard static pedography, the introduced method can be considered to be valid for intraoperative static pedography. During the clinical use, in 44% of the cases a modification of the surgical correction were made after intraoperative pedography in the same surgical procedure


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_12 | Pages 15 - 15
10 Jun 2024
Goodall R Borsky K Harrison C Welck M Malhotra K Rodrigues J
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Background

The Manchester-Oxford Foot Questionnaire (MOxFQ) is a condition specific patient reported outcome measure (PROM) for foot and ankle surgery. It consists of 16 items across three subscales measuring distinct, but related traits: walking/standing ability, pain, and social interaction. Although it is the most used foot and ankle PROM in the UK, initial MOxFQ validation involved analysis of only 100 individuals undergoing hallux valgus surgery. This project aimed to establish whether an individual's response to the MOxFQ varies with anatomical region of disease (measurement invariance), and to explore structural validity of the factor structure (subscale items) of the MOxFQ.

Methods

This was a single-centre, prospective cohort study involving 6640 patients (mean age 52, range 10–90 years) presenting with a wide range of foot and ankle pathologies between 2013 and 2021. Firstly, to assess whether the MOxFQ responses vary by anatomical region of foot and ankle disease, we performed multi-group confirmatory factor analysis. Secondly, to assess the structural validity of the subscale items, exploratory and confirmatory factor analyses were performed.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_14 | Pages 3 - 3
1 Dec 2022
Leardini A Caravaggi P Ortolani M Durante S Belvedere C
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Among the advanced technology developed and tested for orthopaedic surgery, the Rizzoli (IOR) has a long experience on custom-made design and implant of devices for joint and bone replacements. This follows the recent advancements in additive manufacturing, which now allows to obtain products also in metal alloy by deposition of material layer-by-layer according to a digital model. The process starts from medical image, goes through anatomical modelling, prosthesis design, prototyping, and final production in 3D printers and in case post-production. These devices have demonstrated already to be accurate enough to address properly the specific needs and conditions of the patient and of his/her physician. These guarantee also minimum removal of the tissues, partial replacements, no size related issues, minimal invasiveness, limited instrumentation. The thorough preparation of the treatment results also in a considerable shortening of the surgical and of recovery time. The necessary additional efforts and costs of custom-made implants seem to be well balanced by these advantages and savings, which shall include the lower failures and revision surgery rates. This also allows thoughtful optimization of the component-to-bone interfaces, by advanced lattice structures, with topologies mimicking the trabecular bone, possibly to promote osteointegration and to prevent infection. IOR's experience comprises all sub-disciplines and anatomical areas, here mentioned in historical order. Originally, several systems of Patient-Specific instrumentation have been exploited in total knee and total ankle replacements. A few massive osteoarticular reconstructions in the shank and foot for severe bone fractures were performed, starting from mirroring the contralateral area. Something very similar was performed also for pelvic surgery in the Oncology department, where massive skeletal reconstructions for bone tumours are necessary. To this aim, in addition to the standard anatomical modelling, prosthesis design, technical/technological refinements, and manufacturing, surgical guides for the correct execution of the osteotomies are also designed and 3D printed. Another original experience is about en-block replacement of vertebral bodies for severe bone loss, in particular for tumours. In this project, technological and biological aspects have also been addressed, to enhance osteointegration and to diminish the risk of infection. In our series there is also a case of successful custom reconstruction of the anterior chest wall. Initial experiences are in progress also for shoulder and elbow surgery, in particular for pre-op planning and surgical guide design in complex re-alignment osteotomies for severe bone deformities. Also in complex flat-foot deformities, in preparation of surgical corrections, 3D digital reconstruction and 3D printing in cheap ABS filaments have been valuable, for indication, planning of surgery and patient communication; with special materials mimicking bone strength, these 3D physical models are precious also for training and preparation of the surgery. In Paediatric surgery severe multi planar & multifocal deformities in children are addressed with personalized pre-op planning and custom cutting-guides for the necessary osteotomies, most of which require custom allografts. A number of complex hip revision surgeries have been performed, where 3D reconstruction for possible final solutions with exact implants on the remaining bone were developed. Elective surgery has been addressed as well, in particular the customization of an original total ankle replacement designed at IOR. Also a novel system with a high-tibial-osteotomy, including a custom cutting jig and the fixation plate was tested. An initial experience for the design and test of custom ankle & foot orthotics is also in progress, starting with 3D surface scanning of the shank and foot including the plantar aspect. Clearly, for achieving these results, multi-disciplinary teams have been formed, including physicians, radiologists, bioengineers and technologists, working together for the same goal.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_II | Pages 218 - 219
1 Jul 2008
Bell JA Stigant M
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Background: Researchers have measured exposure to sitting using self-reported questionnaires and observational analysis. Such methods are not a reliable measure of daily exposure or sensitive enough to take into account lumbar posture when seated. Recent innovations have produced a fibre-optic goniometer (FOG) that can continuously measure sagittal lumbar posture, although this single sensor is unable to identify if the user is sitting, standing or walking. Methods: A new system was developed utilising a second FOG attached to the hip. Movement characteristics of the hip and lumbar spine were described and used to develop software to predict activity (sitting, standing, walking). Subsequently 10 participants were asked to wear the FOGs for 8 minutes whilst their behaviour was recorded using a video camera. MPEG video sequences were produced and each activity was coded at a point in time and compared against the 2 FOG software model. Results: All Participants found the system comfortable to wear. Validation of the software against the MPEG files showed high sensitivity for sitting (90%), standing (98%), and walking (95%). Positive predictive value was high for sitting (93%), standing (89%) and walking (94%). The overall agreement between video analysis and the FOG software was 92%. Conclusions: Developing the FOG has produced a practical system capable of continuously measuring sedentary workers basic activity in terms of sitting standing and walking. This novel tool will now be used in a prospective study of sedentary workers to determine the influence of seated lumbar posture on the development of LBP


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_10 | Pages 37 - 37
1 Oct 2022
Lutro O Mo S Leta TH Fenstad AM Tjørhom MB Bruun T Hallan G Furnes O Dale H
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Aim

In recent years, many studies on revision for infection after arthroplasty have been published. In national arthroplasty registers, revision for infection is defined as surgical debridement, with or without removal or exchange of the entire or parts of the prosthesis due to deep infection, and should be reported to the register immediately after surgery. The diagnosis of infection is made at the surgeon's discretion, based on pre- and perioperative assessment and evaluation, and is not to be corrected to the register based on peroperative bacterial cultures. Due to this lack of validation, the rate of revision for infection will only be an approximation of the true rate of periprosthetic joint infection (PJI). Our aim was to validate the reporting of infection after total hip arthroplasty, and to assess if revisions for infection actually represented true PJI.

Methods

We investigated the reported revisions for infection and aseptic loosening after total hip arthroplasty from 12 hospitals, representing one region of the country, reported during the period 2010–2020. The electronic patient charts were investigated for information on surgical treatment, use of antibiotics, biochemistry and microbiology findings. PJI was defined as growth of at least two phenotypically identical microbes in perioperative tissue samples. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 22
1 Mar 2002
Zanoli G Padua R Romanini E
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There is no consensus regarding the best method of assessing outcomes after total knee arthroplasty. There are now many questionnaires in the literature, well constructed and validated in the original language. Dawson’s questionnaire (1998) is designed as a 12-item self-administered instrument, and has undergone a complete validation procedure in its original English version. Aim of this paper is to present the procedure of cultural adaptation and some data from the validation process of the Italian version of the questionnaire. Two independent translations into Italian and back-translations into English were obtained, from specialised and general translators. The material was then evaluated in a multidisciplinary panel including elderly patients. A provisional version was obtained and tested in a pilot study. Results and comments were reviewed within the panel again which came up with the final version. The questionnaire was administered to 100 patients scheduled for knee replacement. Other outcomes collected included a general health questionnaire, in its validated Italian version (SF-36), and several objective and radiographic parameters. The burden on the patient and comprehension’s difficulties were registered. Validation included the assessment of internal consistency, construct and content validity. Correlation between different parameters were investigated. Test-retest reliability was assessed on 20 patients. Comparisons with the data presented in the original paper were performed. The questionnaires were accepted favourably by the patients, even though the combination with the SF-36 increased the amount of time required for completion. Some difficulties were registered with the comprehension of the answering method, as well as of the meaning of single items. Results of the validation process were substantially equivalent to those of the original paper


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_1 | Pages 140 - 140
2 Jan 2024
van der Weegen W Warren T Agricola R Das D Siebelt M
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Artificial Intelligence (AI) is becoming more powerful but is barely used to counter the growth in health care burden. AI applications to increase efficiency in orthopedics are rare. We questioned if (1) we could train machine learning (ML) algorithms, based on answers from digitalized history taking questionnaires, to predict treatment of hip osteoartritis (either conservative or surgical); (2) such an algorithm could streamline clinical consultation.

Multiple ML models were trained on 600 annotated (80% training, 20% test) digital history taking questionnaires, acquired before consultation. Best performing models, based on balanced accuracy and optimized automated hyperparameter tuning, were build into our daily clinical orthopedic practice. Fifty patients with hip complaints (>45 years) were prospectively predicted and planned (partly blinded, partly unblinded) for consultation with the physician assistant (conservative) or orthopedic surgeon (operative). Tailored patient information based on the prediction was automatically sent to a smartphone app. Level of evidence: IV.

Random Forest and BernoulliNB were the most accurate ML models (0.75 balanced accuracy). Treatment prediction was correct in 45 out of 50 consultations (90%), p<0.0001 (sign and binomial test). Specialized consultations where conservatively predicted patients were seen by the physician assistant and surgical patients by the orthopedic surgeon were highly appreciated and effective.

Treatment strategy of hip osteoartritis based on answers from digital history taking questionnaires was accurately predicted before patients entered the hospital. This can make outpatient consultation scheduling more efficient and tailor pre-consultation patient education.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_II | Pages 332 - 332
1 Jul 2008
Yousef A Hargin E Hill R Wilson D Walsh D
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Aim: The Système Française D’Arthroscopie (SFA) is a validated method of arthroscopic grading and scoring the knee OA. We have validated a modification of the SFA system for use with digital photographs of pathological samples. Material and Method: After Ethics Committee approval, both tibial plateaux and femoral condyles were collected from 84 patients undergoing total knee replacement or at post mortem. Extent and grading of cartilage changes were documented for the 4 compartments of each sample on a diagram using photographs at standard magnification and illumination, archived, (Photographic Scores). Validation obtained by direct visualisation and probing (Pathological Scores). Radiographic and Histological scoring In addition, each sample was digitally. A second observer (AY) also graded and scored photographic images for 72 compartments of the first 18 cases. Results: For each of the 4 compartments studied, scores ranged from -2.2 to +717.8, representing the full range of possible scores. A statistically significant correlation observed in the study between radiological variables and the severity of chondropathy assessed by our (SFA-path) [ P < 0.005] suggests satisfactory extrinsic validity of this scoring system. And statistically significant correlation [p> 0.0001] between the SFA Path scores of the medial compartment tibial plateau OA and Histologi-cal grade [Minkin] of the same samples. Allocation of scores to diagrams was highly repeatable (Repeatability Coefficient = 50). There was good agreement between Pathological and Photographic Scores (Repeatability Coefficient = 88). There was moderate agreement between Photographic Scores allocated by the 2 observers, with greatest agreement for low (< 200) and high (> 500) scores. Scores for each compartment correlated with scores for each of the other 3 compartments (R values 0.7 to 0.9, all P < 0.005). Conclusion: We validated our modified SFA system which permits scoring of OA severity using digital photographs of pathological samples. SFApath is reliable and repeatable scoring system Our data support the view that OA affects the entire joint, and that a single compartment (e.g. medial tibial plateau) can be taken as broadly representative of the tibiofemoral joint as a whole


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_13 | Pages 142 - 142
1 Nov 2021
Negri S Wang Y Lee S Qin Q Cherief M Hsu GC Xu J Tower RJ Levi B Levin A James A
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Introduction and Objective

Heterotopic ossification is the formation of extraskeletal mineralized tissue commonly associated with either trauma or surgery. While several mouse models have been developed to better characterize the pathologic progression of HO, no model currently exists to study HO of the hip, the most common location of acquired HO in patients. Owing to the unique biological mechanisms underpinning the formation of HO in different tissues, we sought to develop a model to study the post-surgical HO of the hip.

Materials and Methods

Wild-type mice C57BL/6J mice were used to study the procedure outcomes, while Pdgfra-CreERT2;mT/mG and Scx-GFP reporter animals were used for the lineage tracing experiments (total n=16 animals, male, 12 weeks old). An anterolateral approach to the hip was performed. Briefly, a 2 cm incision was made centered on the great trochanter and directed proximal to the iliac crest and distally over the lateral shaft of the femur. The joint was then reached following the intermuscular plane between the rectus femoris and gluteus medius muscles. After the joint was exposed, the articular cartilage was removed using a micropower drill with a 1.2 mm reamer. The medius gluteus and superficial fascia were then re-approximated with Vicryl 5-0 suture (Ethicon Inc, Somerville, NJ) and skin was then closed with Ethilon 5-0 suture (Ethicon Inc). Live high resolution XR imaging was performed every 2 wks to assess the skeletal tissues (Faxitron Bioptics, Tucson, AZ). The images were then scored using the Brooker classification. Ex-vivo microCT was conducted using a Skyscan 1275 scanner (Bruker-MicroCT, Kontich, Belgium). 3D reconstruction and analysis was performed using Dragonfly (ORS Inc., Montreal, Canada). For the histological analysis of specimens, Hematoxylin and Eosin (H&E), modified Goldner's Trichrome (GMT) stainings were performed. Reporter activity was assessed using fluorescent imaging.


Bone & Joint Open
Vol. 4, Issue 10 | Pages 750 - 757
10 Oct 2023
Brenneis M Thewes N Holder J Stief F Braun S

Aims

Accurate skeletal age and final adult height prediction methods in paediatric orthopaedics are crucial for determining optimal timing of growth-guiding interventions and minimizing complications in treatments of various conditions. This study aimed to evaluate the accuracy of final adult height predictions using the central peak height (CPH) method with long leg X-rays and four different multiplier tables.

Methods

This study included 31 patients who underwent temporary hemiepiphysiodesis for varus or valgus deformity of the leg between 2014 and 2020. The skeletal age at surgical intervention was evaluated using the CPH method with long leg radiographs. The true final adult height (FHTRUE) was determined when the growth plates were closed. The final height prediction accuracy of four different multiplier tables (1. Bayley and Pinneau; 2. Paley et al; 3. Sanders – Greulich and Pyle (SGP); and 4. Sanders – peak height velocity (PHV)) was then compared using either skeletal age or chronological age.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_13 | Pages 62 - 62
7 Aug 2023
Khatri C Harrison C Scott C Clement N MacDonald D Metcalfe A Rodrigues J
Full Access

Abstract

Background

The Forgotten Joint Score (FJS) is a 12-item patient reported outcome measurement instrument. It was developed with classical test theory, without testing assumptions such as unidimensionality (all items reflect one underlying factor), appropriate weighting of each item, no differential item function (DIF, different groups answer the same way), and monotonicity (people with higher function have higher score). We applied item response theory (IRT) to improve the validity of FJS to contemporary standards to optimise it for ongoing use.

Research Questions

Does the FJS reflect one latent trait? Can an IRT model be fitted to the FJS to provide interval-scaled measurement?


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_8 | Pages 132 - 132
11 Apr 2023
van Hoogstraten S Arts J
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Malalignment is often postulated as the main reason for the high failure rate of total ankle replacements (TARs). Only a few studies have been performed to correlate radiographic TAR malalignment to the clinical outcome, but no consistent trends between TAR alignment parameters and the clinical outcome were found. No standard TAR alignment measurement method is present, so reliable comparison between studies is difficult. Standardizing TAR alignment measurements and increasing measurable parameters on radiographs in the clinic might lead to a better insight into the correlation between malalignment and the clinical outcome. This study aims to develop and validate a tool to semi-automatic measure TAR alignment, and to improve alignment measurement on radiographs in the clinic.

A tool to semi-automatically measure TAR alignment on anteroposterior and lateral radiographs was developed and used by two observers to measure TAR alignment parameters of ten patients. The Intraclass Coefficient (ICC) was calculated and accuracy was compared to the manual measurement method commonly used in the clinic.

The tool showed an accuracy of 76% compared to 71% for the method used during follow-up in the clinic. ICC values were 0.94 (p<0.01) and higher for both inter-and intra-observer reliability.

The tool presents an accurate, consistent, and reliable method to measure TAR alignment parameters. Three-dimensional alignment parameters are obtained from two-dimensional radiographs, and as the tool can be applied to any TAR design, it offers a valuable addition in the clinic and for research purposes.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIII | Pages 37 - 37
1 May 2012
Osborne R Bucknill A De Steiger R Brand C Graves S
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As there is currently no evidenced-based and systematic way of prioritising people requiring JRS we aimed to develop a clinically relevant system to improve prioritisation of people who may require JRS. An important challenge in this area is to accurately assign a queue position and improve list management. To identify priority criteria areas eight workshops were held with surgeons and patients. Domains derived were pain, activity limitations, psychosocial wellbeing, economic impact and deterioration. Draft questions were developed and refined through structured interviews with patients and consultation with consultants. 38 items survived critical appraisal and were mailed to 600 patients. Eleven items survived clinimetric and statistical item reduction. Validation then included co-administration with standardised questionnaires (960 patients), verification of patient MAPT scores through clinical interview, examination of concordance with surgeon global ratings and test-retest. Ninety-six Victorian surgeons weighted items using Discrete Choice Experiments (DCEs). The DCE scaling generated a scale, which clearly ranked patients across the disease continuum. The MAPT differentiated people on or not on waiting lists (p<0.001), and was highly correlated with other questionnaires, e.g., unweighted-MAPT vs WOMAC (r=0.78), Oxford Hip/Knee (r=0.86/0.75), Quality of Life (r=0.78), Depression (r=0.64), Anxiety (r=0.60), p<0.001 for all. Test-retest was excellent (ICC=0.89, n=90). Cronbachs reliability was also high 0.85. The MAPT is now routinely administered across all Victorian hospitals undertaking arthroplasty where the response rate is generally above 90%. In the hands of clinicians the MAPT has been used to facilitate fast-tracking of patients with the greatest need, monitoring for deterioration in those waiting for surgery or having a trial of non-operative treatment and deferment of surgery for those that may benefit from further non-operative treatments. The MAPT is short, easy to complete and clinically relevant. It is a specific measure of severity of hip/knee arthritis and assigns priority for surgery. It has excellent psychometric and clinimetric properties evidenced by concordance with standard disease-specific and generic scales and widespread use and endorsement across health services


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_8 | Pages 5 - 5
1 Aug 2022
Wardell D Jayasuriya R Totton N Mills A Breakwell L Cole A
Full Access

Thermal sensors have been used in bracing research as self-reported diaries are inaccurate. Little is known about new low-profile sensors, optimal location within a brace, locational thermal micro-climate and effect of brace lining. Our objective is to Determine an optimal temperature threshold for sensor-measured and true wear time agreement. Identify optimal sensor location. Assess all factors to determine the best sensor option for the Bracing AdoleScent Idiopathic Scoliosis (BASIS) multicentre RCT.

Seven Orthotimer and five iButton (DS1925L) sensors were synchronised to record temperature at five-minute intervals. Three healthy participants donned a rigid spinal brace, embedded with both sensors across four anatomical locations (abdomen/axilla/lateral-gluteal/sacral). Universal-coordinated-time wear protocols were performed in/out-doors. Intraclass correlation coefficient (ICC) assessed sensor-measured and true wear time agreement at thresholds 15–36oC.

Optimal thresholds, determined by largest ICC estimate: Orthotimer: Abdomen=26oC, axilla=27oC, lateral-gluteal=24.5oC, sacral=22.5oC. iButton: Abdomen=26oC, axilla=27oC, lateral-gluteal=23.5oC, sacral=23.5oC. Warm-up time and error at optimal thresholds increased for moulded sensors covered with 6mm lining.

Location: anterior abdominal wall. Excellent reliability and higher optimal thresholds, less likely to be exceeded by ambient temperature; not a pressure area. Sensor: iButton, longer battery life and larger memory than Orthotimer; allows recording at 10 min intervals for life of brace. Orthotimer only able to record every 30 mins, increasing error between true and measured wear time; Orthotimer needs 6-monthly data download. Threshold: 26oC is optimal threshold to balance warm-up and cool-down times for accurately measuring wear time. Sensor should not be covered by lining foam as this significantly prolongs warm-up time.


Bone & Joint Research
Vol. 12, Issue 8 | Pages 494 - 496
9 Aug 2023
Clement ND Simpson AHRW

Cite this article: Bone Joint Res 2023;12(8):494–496.


Bone & Joint Research
Vol. 13, Issue 1 | Pages 19 - 27
5 Jan 2024
Baertl S Rupp M Kerschbaum M Morgenstern M Baumann F Pfeifer C Worlicek M Popp D Amanatullah DF Alt V

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.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_II | Pages 260 - 260
1 Jul 2008
NOGIER A SAILLANT G SARI-ALI H MARCOVSHI S TEMPLIER A SKALLI W
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Purpose of the study: The mean rotation center (MRC) characterizes the movement of two solids in relation to each other. This parameter has been proposed for the cervical spine to describe the motion of vertebral segments. Two lateral views (flexion and extension) are required to draw the necessary lines and establish the centers of rotation. The process is rigorous but time-consuming. We validated a computerized analysis system for automatic determination of the cervical MRC and study the localizations observed in healthy subjects. Material and methods: Validation of the computerized system. Accurate angle measurements: nine cervical spines were harvested from anatomic specimens. A K-wire was inserted sagittally into each vertebra. Lateral images were obtain in flexion and extension. The measurements of mobility made by the software were compared with manual measurements. Reproducibility tests (intra- and interobserver): six pairs of flexion and extension views in healthy subjects. Two different observers made fifteen successive measurements of each MRC for each spinal segment. Frequently encountered positions of the MRC in healthy subjects: stress films were obtained in 51 healthy subjects aged 18–40 years. For each spinal segment, the MCR was determined with the computerized system. Results: Accuracy of the angle measurements: the precision was 1.4° for a 95% interval of confidence. Reproducibility: variability of the position in X and Y for the MRC (expressed in percent of the size of the vertebral body) was: 19.6 and 24.5 for C2–C3; 112 and 15.3 for C3–C4; 7.7 and 9.4 for C4–C5; 9.1 and 9.4 for C5–C6; 13.1 and 11.8 for C6–C7. Positions frequently encountered in healthy subjects: the most frequent position of the MRC varied from one segment to another. There was a frequent position for each segment. These frequent positions were situated in the posterosuperior quadrant of the subjacent vertebra for C2–C3, C3–C4, C4–C5, and C5–C6. For C6–C7, the frequent positions for MRC were at the level of the intervertebral space, behind the center of the disc. Discussion: The software tested here appeared to provide good measurements for cervical spine from C3 to C7. At these levels, the measures were accurate and reproducible, as were the coordinates for the MCR of each segment. The frequent positions of the MRC found in this study are the same as reported by other authors. This method is easy to apply in routine practice


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_17 | Pages 87 - 87
24 Nov 2023
De Bleeckere A Vandendriessche S Messiaen A Crabbé A Boelens J Coenye T
Full Access

Aim

There is growing evidence that bacteria encountered in periprosthetic joint infections (PJI) form surface-attached biofilms on prostheses, as well as biofilm aggregates embedded in synovial fluid and tissues. However, models allowing the investigation of these biofilms and the assessment of their antimicrobial susceptibility in physiologically relevant conditions are currently lacking. To address this, we developed a synthetic synovial fluid (SSF) model and we validated this model in terms of growth, aggregate formation and antimicrobial susceptibility testing, using multiple PJI isolates.

Methods

17 PJI isolates were included, belonging to Staphylococcus aureus, coagulase negative staphylococci, Cutibacterium acnes, Pseudomonas aeruginosa, enterococci, streptococci, Candida species and Enterobacterales. Growth and aggregate formation in SSF, under microaerophilic or anaerobic conditions, were evaluated using light microscopy. The biofilm preventing concentration (BPC) and minimum biofilm inhibitory concentration (MBIC) of relevant antibiotics (doxycyclin, rifampicin and oxacillin) were determined for the staphylococcal strains (n=8). To this end, a high throughput approach was developed, using a fluorescent viability resazurin staining. BPC and MBIC values were compared to the minimum inhibitory concentration (MIC) obtained with conventional methods.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 37 - 37
2 May 2024
Green J Malviya A Reed M
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OpenPredictor, a machine learning-enabled clinical decision aid, has been developed to manage backlogs in elective surgeries. It aims to optimise the use of high volume, low complexity surgical pathways by accurately stratifying patient risk, thereby facilitating the allocation of patients to the most suitable surgical sites. The tool augments elective surgical pathways by providing automated secondary opinions for perioperative risk assessments, enhancing decision-making. Its primary application is in elective sites utilising lighter pre-assessment methods, identifying patients with minimal complication risks and those high-risk individuals who may benefit from early pre-assessment.

The Phase 1 clinical evaluation of OpenPredictor entailed a prospective analysis of 156 patient records from elective hip and knee joint replacement surgeries. Using a polynomial logistic regression model, patients were categorised into high, moderate, and low-risk groups. This categorisation incorporated data from various sources, including patient demographics, co-morbidities, blood tests, and overall health status.

In identifying patients at risk of postoperative complications, OpenPredictor demonstrated parity with consultant-led preoperative assessments. It accurately flagged 70% of patients who later experienced complications as moderate or high risk. The tool's efficiency in risk prediction was evidenced by its balanced accuracy (75.6%), sensitivity (70% with a 95% confidence interval of 62.05% to 76.91%), and a high negative predictive value (96.7%).

OpenPredictor presents a scalable and consistent solution for managing elective surgery pathways, comparable in performance to secondary consultant opinions. Its integration into pre-assessment workflows assists in efficient patient categorisation, reduces late surgery cancellations, and optimises resource allocation. The Phase 1 evaluation of OpenPredictor underscores its potential for broader clinical application and highlights the need for ongoing data refinement and system integration to enhance its performance.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_8 | Pages 4 - 4
10 May 2024
Hoffman T Knudsen J Jesani S Clark H
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Introduction

Debridement, antibiotics irrigation and implant retention (DAIR) is a common management strategy for hip and knee prosthetic joint infections (PJI). However, failure rates remain high, which has led to the development of predictive tools to help determine success. These tools include KLIC and CRIME80 for acute-postoperative (AP) and acute haematogenous (AH) PJI respectively. We investigated whether these tools were applicable to a Waikato cohort.

Method

We performed a retrospective cohort study that evaluated patients who underwent DAIR between January 2010 and June 2020 at Waikato Hospital. Pre-operative KLIC and CRIME80 scores were calculated and compared to success of operation. Failure was defined as: (i) need for further surgery, (ii) need for suppressive antibiotics, (iii) death due to the infection. Logistic regression models were used to calculate the area under the curve (AUC).


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_8 | Pages 63 - 63
11 Apr 2023
Pastor T Knobe M Kastner P Souleiman F Pastor T Gueorguiev B Windolf M Buschbaum J
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Freehand distal interlocking of intramedullary nails is technical demanding and prone to handling issues. It requires the surgeon to precisely place a screw through the nail under x-ray. If not performed accurately it can be a time consuming and radiation expensive procedure. The aims of this study were to assess construct and face validity of a new training device for distal interlocking of intramedullary nails.

53 participants (29 novices and 24 experts) were included. Construct validity was evaluated by comparing simulator metrics (number of x-rays, nail hole roundness, drill tip position and accuracy of the drilled hole) between experts and novices. Face validity was evaluated by means of a questionnaire concerning training potential and quality of simulated reality using a 7-point Likert scale (range 1-7).

Mean realism of the training device was rated 6.3 (range 4-7) and mean training potential as well as need for distal interlocking training was rated 6.5 (range 5-7) with no significant differences between experts and novices, p≥0.236. All participants stated that the simulator is useful for procedural training of distal nail interlocking, 96% would like to have it at their institution and 98% would recommend it to their colleagues. Total number of x-rays were significantly higher for novices (20.9±6.4 vs. 15.5±5.3), p=0.003. Successful task completion (hit the virtual nail hole with the drill) was significantly higher in experts (p=0.04; novices hit: n=12; 44,4%; experts hit: n=19; 83%).

The evaluated training device for distal interlocking of intramedullary nails yielded high scores in terms of training capability and realism. Furthermore, construct validity was established as it reliably discriminates between experts and novices. Participants see a high further training potential as the system may be easily adapted to other surgical task requiring screw or pin position with the help of x-rays.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 49 - 49
1 Mar 2006
Scheerlinck T de Mey J Deklerck R
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Software to segment and to analyse connective CT-scan images of the bone-cement-stem complex was developed and validated. Parameters assessed included: volumes (cortical bone, cancelous bone, cement, stem, air in bone and air in cement), cement mantle thickness, cortical & cancelous bone thickness, contact surface area between cement and bone, degree of centralisation (stem in cement, stem and cement in cancelous and in cortical bone). To validate and assess intra- and interob-server reliability two models were implanted in two dried macerated cadaver femurs using a third generation cementing technique. In the first a polished tapered stem (CPT, Zimmer) was cemented and removed after cement curing. The air filled cavity within the cement mantle could be identified as implant, avoiding metallic scatter artefacts. The second model (SLA) used a plastic stem prototype produced by computer design and a rapid prototyping stereolithographic technique. This model does not need to be removed before CT-scanning and allows assessment of whatever femoral implant. Validation occurred by comparing 41 manually segmented femoral cross-sections (25 CPT, 16 SLA) with data of corresponding CT-scan slices. Inter-observer reliability was assessed by having the same person performing the CT-scan and the analysis of both models four times. To assess intra-observer reliability, four different observers segmented 97 representative CT-images (46 CPT, 51 SLA). The average accuracy for surfaces areas (bone, cement, stem) within CT-images was 7.47 mm2 (1.80%), bone & cement mantle thickness: 0.51 mm (9.39%), distances between centroids (stem-cement, stem-bone, cement-bone): 0.38 mm (18.5%) and contours (bone, cement): 0.27 mm (2.57%). The intra- and interobserver reliability of air content in bone and cement was suboptimal (intraclass-correlation coefficient (ICC) as low as 0.54, average ICC: 0.85). All other variables assessed were reliable (ICC > 0.81, average ICC: 0.96). Validity and reliability were comparable when assessed separately for the proximal, middle and distal third of both models. This in vitro technique can assess characteristics of cement mantles produced by different cementing techniques, centralizers and existing femoral implants or stem prototypes


Bone & Joint Open
Vol. 3, Issue 3 | Pages 211 - 217
1 Mar 2022
Hsu C Chen C Wang S Huang J Tong K Huang K

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.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_13 | Pages 97 - 97
1 Dec 2022
Burke Z Lazarides A Gundavda M Griffin A Tsoi K Ferguson P Wunder JS
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Traditional staging systems for high grade osteosarcoma (Enneking, MSTS) are based largely on gross surgical margins and were developed before the widespread use of neoadjuvant chemotherapy. It is now well known that both microscopic margins and chemotherapy are predictors of local recurrence. However, neither of these variables are used in the traditional surgical staging and the precise safe margin distance is debated. Recently, a novel staging system utilizing a 2mm margin cutoff and incorporating precent necrosis was proposed and demonstrated improved prognostic value for local recurrence free survival (LRFS) when compared to the MSTS staging system. This staging system has not been validated beyond the original patient cohort. We propose to analyze this staging system in a cohort of patients with high-grade osteosarcoma, as well as evaluate the ability of additional variables to predict the risk of local recurrence and overall survival.

A retrospective review of a prospectively collected database of all sarcoma patients between 1985 and 2020 at a tertiary sarcoma care center was performed. All patients with high-grade osteosarcoma receiving neo-adjuvant chemotherapy and with no evidence of metastatic disease on presentation were isolated and analyzed. A minimum of two year follow up was used for surviving patients. A total of 225 patients were identified meeting these criteria. Univariate analysis was performed to evaluate variable that were associated with LRFS. Multivariate analysis is used to further analyze factors associated with LRFS on univariate analysis.

There were 20 patients (8.9%) who had locally recurrent disease. Five-year LRFS was significantly different for patients with surgical margins 2mm or less (77.6% v. 93.3%; p=0.006) and those with a central tumor location (67.9 v. 94.4; <0.001). A four-tiered staging system using 2mm surgical margins and a percent necrosis of 90% of greater was also a significant predictor of 5-year LRFS (p=0.019) in this cohort. Notably, percent necrosis in isolation was not a predictor of LRFS in this cohort (p=0.875). Tumor size, gender, and type of surgery (amputation v. limb salvage) were also analyzed and not associated with LRFS. The MSTS surgical margin staging system did not significantly stratify groups (0.066).

A 2mm surgical margin cutoff was predictive of 5-year LRFS in this cohort of patients with localized high-grade osteosarcoma and a combination of a 2mm margin and percent necrosis outperformed the prognostic value of the traditional MSTS staging system. Utilization of this system may improve the ability of surgeons to stage thier patients. Additional variables may increase the value of this system and further validation is required.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_7 | Pages 90 - 90
4 Apr 2023
Sharma M Khanal P Patel N Patel A
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To investigate the utility of virtual reality (VR) simulators in improving surgical proficiency in Orthopaedic trainees for complex procedures and techniques.

Fifteen specialty surgeons attending a London Orthopaedic training course were randomised to either the VR (n = 7) or control group (n = 8). All participants were provided a study pack comprising an application manual and instructional video for the Trochanteric Femoral Nail Advanced (TFNA) procedure. The VR group underwent additional training for TFNA using the DePuy Synthes (Johnson and Johnson) VR simulator. All surgeons were then observed applying the TFNA in a Sawbones model and assessed by a blinded senior consultant using three metrics: time to completion, 22-item procedure checklist and 5-point global assessment scale.

Participant demographics for the VR and control groups were similar in context of age (mean [SD]: VR group, 31.0 [2.38] years; control group, 30.6 [2.39] years), gender (VR group, 5 [71%] men; control group, 8 [100%] men) and prior experience with TFNA (had applied TFNA as primary surgeon: VR group, 6 [86%]; control group, 7 [88%]). Although statistical significance was not reached, the VR group, on average, outperformed the control group on all three metrics. They completed the TFNA procedure faster (mean [SD]: 18.2 [2.16] minutes versus 19.78 [1.32] minutes; p<0.189), performed a greater percentage of steps correctly (79% versus 66%; p<0.189) and scored a higher percentage on the global assessment scale (75% versus 65%; p<0.232).

VR simulators offer a safe and accessible means for Orthopaedic trainees to prepare for and supplement their theatre-based experience. It is vital, therefore, to review and validate novel simulation-based systems and in turn facilitate their improvement. We intend to increase our sample size and expand this preliminary study through a second upcoming surgical course for Orthopaedic trainees in London.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_16 | Pages 62 - 62
1 Dec 2021
Carregosa A Dewitt S Aeschlimann D
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Abstract

Objectives

Despite overwhelming need, with about 9 million osteoarthritis (OA) sufferers in UK alone, little progress has been made towards pathogenesis-based categorising of patients and subsequent intervention. Experimental studies relied heavily on animal models, which is inefficient and expensive, and has often produced drugs failing in phase I/II clinical trials due to off-target side effects or failure to predict human disease in animal models. This project aims to address this challenge by developing a scalable in vitro human organotypic tissue model. The model can be used to simulate OA processes and ultimately, exploited to seek biomarkers for early diagnosis or screen potential drugs for efficacy.

Methods

We have previously shown that a stratified 3D-tissue akin of articular cartilage can be generated over a 35-day period using a tissue engineering approach with primary human chondrocyte progenitor cells. The engineered tissue mimics native cartilage both in structural organization and biochemical composition. Here, we explore the influence of the nature and homogeneity of initial cell population on cartilage development and maturation.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_15 | Pages 68 - 68
7 Nov 2023
Hohmann E Paschos N Keough N Molepo M Oberholster A Erbulut D Tetsworth K Glat V Gueorguiev B
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The purpose of this study was to develop a quality appraisal tool for the assessment of laboratory basic science biomechanical studies.

Materials andScore development comprised of the following phases: item identification/development, item reduction, content/face/criterion validity, weighting, test-retest reliability and internal consistency. For item identification/development, the panel was asked to independently list criteria and factors they considered important for cadaver study and generate items that should be used to appraise cadaver study quality. For content validity, the content validity ratio (CVR) was calculated. The minimum accepted content validity index (CVI) was set to 0.85. For weighting, equal weight for each item was 6.7% [15 items]. Based on these figures the panel was asked to either upscale or downscale the weight for each item ensuring that the final sum for all items was 100%. Face validity was assessed by each panel member using a Likert scale from 1–7. Strong face validity was defined as a mean score of >5. Test-retest reliability was assessed using 10 randomly selected studies. Criterion validity was assessed using the QUACS scale as standard. Internal consistency was assessed using Cronbach's alpha.

Five items reached a CVI of 1 and 10 items a CVI of 0.875. For weighting five items reached a final weight of 10% and ten items 5%. The mean score for face validity was 5.6. Test-retest reliability ranged from 0.78–1.00 with 9 items reaching a perfect score. Criterion validity was 0.76 and considered to be strong. Cronbach's alpha was calculated to be 0.71 indicating acceptable internal consistency.

The new proposed quality score for basic science studies consists of 15 items and has been shown to be reliable, valid and of acceptable internal consistency. It is suggested that this score should be utilised when assessing basic science studies.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_2 | Pages 134 - 134
2 Jan 2024
Ghezzi D Sartori M Boi M Montesissa M Sassoni E Fini M Baldini N Cappelletti M Graziani G
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Prosthetic joint infections represent complications connected to the implantation of biomedical devices, they have high incidence, interfere with osseointegration, and lead to a high societal burden. The microbial biofilm, which is a complex structure of microbial cells firmly attached to a surface, is one of the main issues causing infections. Biofilm- forming bacteria are acquiring more and more resistances to common clinical treatments due to the abuse of antibiotics administration. Therefore, there is increasing need to develop alternative methods exerting antibacterial activities against multidrug-resistant biofilm-forming bacteria. In this context, metal-based coatings with antimicrobial activities have been investigated and are currently used in the clinical practice. However, traditional coatings exhibit some drawbacks related to the insufficient adhesion to the substrate, scarce uniformity and scarce control over the toxic metal release reducing their efficacy. Here, we propose the use of antimicrobial silver-based nanostructured thin films to discourage bacterial infections. Coatings are obtained by Ionized Jet Deposition, a plasma-assisted technique that permits to manufacture films of submicrometric thickness having a nanostructured surface texture, allow tuning silver release, and avoid delamination. To mitigate interference with osseointegration, here silver composites with bone apatite and hydroxyapatite were explored. The antibacterial efficacy of silver films was tested in vitro against gram- positive and gram-negative species to determine the optimal coatings characteristics by assessing reduction of bacterial viability, adhesion to substrate, and biofilm formation. Efficacy was tested in an in vivo rabbit model, using a multidrug-resistant strain of Staphylococcus aureus showing significant reduction of the bacterial load on the silver prosthesis both when coated with the metal only (>99% reduction) and when in combination with bone apatite (>86% reduction). These studies indicate that IJD films are highly tunable and can be a promising route to overcome the main challenges in orthopedic prostheses.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 110 - 110
23 Feb 2023
Francis S Murphy B Elsiwy Y Babazadeh S Clement N Stoney J Stevens J
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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.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_9 | Pages 4 - 4
1 Jun 2021
Jenny J Banks S Baldairon F
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INTRODUCTION

The restoration of physiological kinematics is one of the goals of a total knee arthroplasty (TKA). Navigation systems have been developed to allow an accurate and precise placement of the implants. But its application to the intraoperative measurement of knee kinematics has not been validated. The hypothesis of this study was that the measurement of the knee axis, femoral rotation, femoral translation with respect to the tibia, and medial and lateral femorotibial gaps during continuous passive knee flexion by the navigation system would be different from that by fluoroscopy taken as reference.

MATERIAL – METHODS

Five pairs of knees of preserved specimens were used. The e.Motion FP ® TKA (B-Braun Aesculap, Tuttlingen, Germany) was implanted using the OrthoPilot TKA 4.3 version and Kobe version navigation system (B-Braun Aesculap, Tuttlingen, Germany). Kinematic recording by the navigation system was performed simultaneously with fluoroscopic recording during a continuous passive flexion-extension movement of the prosthetic knee. Kinematic parameters were extracted from the fluoroscopic recordings by image processing using JointTrack Auto ® software (University of Florida, Gainesville, USA). The main criteria were the axis of the knee measured by the angle between the center of the femoral head, the center of the knee and the center of the ankle (HKA), femoral rotation, femoral translation with respect to the tibia, and medial and lateral femorotibial gaps. The data analysis was performed by a Kappa correlation test. The agreement of the measurements was assessed using the intraclass correlation coefficient (ICC) and its 95% confidence interval.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_2 | Pages 39 - 39
10 Feb 2023
Lutter C Grupp T Mittelmeier W Selig M Grover P Dreischarf M Rose G Bien T
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Polyethylene wear represents a significant risk factor for the long-term success of knee arthroplasty [1]. This work aimed to develop and in vivo validate an automated algorithm for accurate and precise AI based wear measurement in knee arthroplasty using clinical AP radiographs for scientifically meaningful multi-centre studies.

Twenty postoperative radiographs (knee joint AP in standing position) after knee arthroplasty were analysed using the novel algorithm. A convolutional neural network-based segmentation is used to localize the implant components on the X-Ray, and a 2D-3D registration of the CAD implant models precisely calculates the three-dimensional position and orientation of the implants in the joint at the time of acquisition. From this, the minimal distance between the involved implant components is determined, and its postoperative change over time enables the determination of wear in the radiographs.

The measured minimum inlay height of 335 unloaded inlays excluding the weight-induced deformation, served as ground truth for validation and was compared to the algorithmically calculated component distances from 20 radiographs.

With an average weight of 94 kg in the studied TKA patient cohort, it was determined that an average inlay height of 6.160 mm is expected in the patient. Based on the radiographs, the algorithm calculated a minimum component distance of 6.158 mm (SD = 81 µm), which deviated by 2 µm in comparison to the expected inlay height.

An automated method was presented that allows accurate and precise determination of the inlay height and subsequently the wear in knee arthroplasty based on a clinical radiograph and the CAD models. Precision and accuracy are comparable to the current gold standard RSA [2], but without relying on special radiographic setups. The developed method can therefore be used to objectively investigate novel implant materials with meaningful clinical cohorts, thus improving the quality of patient care.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_13 | Pages 59 - 59
1 Dec 2022
Hiemstra LA Bentrim A Kerslake S Lafave M
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The Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0) is a patient-reported disease-specific quality of life (QOL) outcome measure used to assess patients with recurrent lateral patellofemoral instability (LPI) both pre- and post-operatively. The purpose of this study was to compare the BPII 2.0 to four other relevant patient reported outcome measures (PROMs): the Tampa Scale-11 for kinesiophobia (TSK-11), the pain catastrophizing scale (PCS), a general QOL (EQ-5D-5L), and a return to sport index (ACL-RSI). This concurrent validation sought to compare and correlate the BPII 2.0 with these other measures of physical, psychological, and emotional health. The psychological and emotional status of patients can impact recovery and rehabilitation, and therefore a disease-specific PROM may be unable to consistently identify patients who would benefit from interventions encompassing a holistic and person-focused approach in addition to disease-specific treatment.

One hundred and ten patients with recurrent lateral patellofemoral instability (LPI) were assessed at a tertiary orthopaedic practice between January and October 2021. Patients were consented into the study and asked to complete five questionnaires: the BPII 2.0, TSK-11, PCS, EQ-5D-5L, and the ACL-RSI at their initial orthopaedic consultation. Descriptive demographic statistics were collected for all patients. A Pearson's r correlation coefficient was employed to examine the relationships between the five PROMs. These analyses were computed using SPSS 28.0 © (IBM Corporation, 2021).

One hundred and ten patients with a mean age of 25.7 (SD = 9.8) completed the five PROMs. There were 29 males (26.3%) and 81 females (73.6%) involving 50% symptomatic left knees and 50% symptomatic right knees. The mean age of the first dislocation was 15.4 years (SD = 7.3; 1-6) and the mean BMI was 26.5 (SD = 7.3; range = 12.5-52.6) The results of the Pearson's r correlation coefficient demonstrated that the BPII 2.0 was statistically significantly related to all of the assessed PROM's (p

There was significant correlation evident between the BPII 2.0 and the four other PROMs assessed in this study. The BPII 2.0 does not explicitly measure kinesiophobia or pain catastrophizing, however, the significant statistical relationship of the TSK-11 and PCS to the BPII 2.0 suggests that this information is being captured and reflected. The preliminary results of this concurrent validation suggest that the pre-operative data may offer predictive validity. Future research will explore the ability of the BPII 2.0 to predict patient quality of life following surgery.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_15 | Pages 76 - 76
1 Dec 2021
Mannala G Rupp M Alagboso F Docheva D Alt V
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Aim

In vivo biofilm models play major role to study biofilm development, morphology, and regulatory molecules involve in biofilm. Due to ethical restrictions, the use mammalian models are replaced with other alternative models in basic research. Recently, we have developed insect infection model G. mellonella larvae to study implant associated biofilm infections. This model organism is easy to handle, cheap and ethical restriction free and could be used for the high through put screening of antimicrobial compounds to treat biofilm. To promote the use of this model in basic research we aimed to validate this based on the typical biofilm features such as less susceptible to the antibiotics, complexity of the biofilm structure and gene expression profile of biofilms.

Method

G. mellonella larvae are maintained at 30oC on artificial diet in an incubator. Titanium and Stainless steel K-wires were cut into small pieces with size of 4mm. After sterilization with 100% alcohol, these K-wires were pre-incubated in S. aureus bacterial suspension (5×106 CFU/ml) for 30 min, washed in PBS and implanted inside the larva after with help of scalpel. The larvae were incubated at 37oC for two day for the survival analysis. To analyze the less susceptibility of the biofilms towards antibiotics, the larvae were treated with gentamicin and compared survival with planktonic infection in G. mellonella. To reveal the complex structure of biofilm, the implants were removed and processed for the MALDI analysis. Whole genome-based transcriptome of biofilm was performed to explore the changes in transcriptional landscapes.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_4 | Pages 74 - 74
1 Mar 2021
Meynen A Verhaegen F Debeer P Scheys L
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During shoulder arthroplasty the native functionality of the diseased shoulder joint is restored, this functionality is strongly dependent upon the native anatomy of the pre-diseased shoulder joint. Therefore, surgeons often use the healthy contralateral scapula to plan the surgery, however in bilateral diseases such as osteoarthritis this is not always feasible. Virtual reconstructions are then used to reconstruct the pre-diseased anatomy and plan surgery or subject-specific implants. In this project, we develop and validate a statistical shape modeling method to reconstruct the pre-diseased anatomy of eroded scapulae with the aim to investigate the existence of predisposing anatomy for certain shoulder conditions.

The training dataset for the statistical shape model consisted of 110 CT images from patients without observable scapulae pathologies as judged by an experienced shoulder surgeon. 3D scapulae models were constructed from the segmented images. An open-source non-rigid B-spline-based registration algorithm was used to obtain point-to-point correspondences between the models. The statistical shape model was then constructed from the dataset using principle component analysis. The cross-validation was performed similarly to the procedure described by Plessers et al. Virtual defects were created on each of the training set models, which closely resemble the morphology of glenoid defects according to the Wallace classification method. The statistical shape model was reconstructed using the leave-one-out method, so the corresponding training set model is no longer incorporated in the shape model. Scapula reconstruction was performed using a Monte Carlo Markov chain algorithm, random walk proposals included both shape and pose parameters, the closest fitting proposal was selected for the virtual reconstruction. Automatic 3D measurements were performed on both the training and reconstructed 3D models, including glenoid version, critical shoulder angle, glenoid offset and glenoid center position.

The root-mean-square error between the measurements of the training data and reconstructed models was calculated for the different severities of glenoid defects. For the least severe defect, the mean error on the inclination, version and critical shoulder angle (°) was 2.22 (± 1.60 SD), 2.59 (± 1.86 SD) and 1.92 (± 1.44 SD) respectively. The reconstructed models predicted the native glenoid offset and centre position (mm) an accuracy of 0.87 (± 0.96 SD) and 0.88 (± 0.57 SD) respectively. The overall reconstruction error was 0.71 mm for the reconstructed part. For larger defects each error measurement increased significantly.

A virtual reconstruction methodology was developed which can predict glenoid parameters with high accuracy. This tool will be used in the planning of shoulder surgeries and investigation of predisposing scapular morphologies.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_12 | Pages 71 - 71
1 Dec 2022
Pelletier-Roy R Dionne A Richard-Denis A Briand M Bourassa-Moreau E Mac-Thiong J
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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.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_12 | Pages 8 - 8
1 Dec 2022
Pelletier-Roy R Dionne A Richard-Denis A Briand M Bourassa-Moreau E Mac-Thiong J
Full Access

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.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_13 | Pages 43 - 43
1 Dec 2022
Pelletier-Roy R Dionne A Richard-Denis A Briand M Bourassa-Moreau E Mac-Thiong J
Full Access

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.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_5 | Pages 9 - 9
1 Mar 2021
Trebše N Pokorn M
Full Access

Aim

Kingella kingae seems to be the most common cause of osteoarticular infections (OAI) in children under 48 months of age (1). Recent studies had shown that K. kingae is poorly susceptible to anti-staphylococcal penicillin and some isolates produce beta-lactamase (2). This led to the need for new treatment guidelines for OAI in populations in which K. kingae is frequent. Our study aimed to design a model which could predict K. kingae OAI in order to initiate appropriate empirical treatment on hospital admission.

Method

We performed a retrospective cohort study in children from 1 month to 15 years old diagnosed with OAI, hospitalized between 2006 and 2018. Mann-Whitney test and Fisher's exact test were used for data analysis. The model predicting K. kingae OAI was designed using logistic regression.


Bone & Joint Research
Vol. 10, Issue 3 | Pages 173 - 187
1 Mar 2021
Khury F Fuchs M Awan Malik H Leiprecht J Reichel H Faschingbauer M

Aims

To explore the clinical relevance of joint space width (JSW) narrowing on standardized-flexion (SF) radiographs in the assessment of cartilage degeneration in specific subregions seen on MRI sequences in knee osteoarthritis (OA) with neutral, valgus, and varus alignments, and potential planning of partial knee arthroplasty.

Methods

We retrospectively reviewed 639 subjects, aged 45 to 79 years, in the Osteoarthritis Initiative (OAI) study, who had symptomatic knees with Kellgren and Lawrence grade 2 to 4. Knees were categorized as neutral, valgus, and varus knees by measuring hip-knee-angles on hip-knee-ankle radiographs. Femorotibial JSW was measured on posteroanterior SF radiographs using a special software. The femorotibial compartment was divided into 16 subregions, and MR-tomographic measurements of cartilage volume, thickness, and subchondral bone area were documented. Linear regression with adjustment for age, sex, body mass index, and Kellgren and Lawrence grade was used.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_1 | Pages 68 - 68
1 Feb 2020
Gascoyne T Pejhan S Bohm E Wyss U
Full Access

Background

The anatomy of the human knee is very different than the tibiofemoral surface geometry of most modern total knee replacements (TKRs). Many TKRs are designed with simplified articulating surfaces that are mediolaterally symmetrical, resulting in non-natural patterns of motion of the knee joint [1]. Recent orthopaedic trends portray a shift away from basic tibiofemoral geometry towards designs which better replicate natural knee kinematics by adding constraint to the medial condyle and decreasing constraint on the lateral condyle [2]. A recent design concept has paired this theory with the concept of guided kinematic motion throughout the flexion range [3]. The purpose of this study was to validate the kinematic pattern of motion of the surface-guided knee concept through in vitro, mechanical testing.

Methods

Prototypes of the surface-guided knee implant were manufactured using cobalt chromium alloy (femoral component) and ultra-high molecular weight polyethylene (tibial component). The prototypes were installed in a force-controlled knee wear simulator (AMTI, Watertown, MA) to assess kinematic behavior of the tibiofemoral articulation (Figure 1). Axial joint load and knee flexion experienced during lunging and squatting exercises were extracted from literature and used as the primary inputs for the test. Anteroposterior and internal-external rotation of the implant components were left unconstrained so as to be passively driven by the tibiofemoral surface geometry. One hundred cycles of each exercise were performed on the simulator at 0.33 Hz using diluted bovine calf serum as the articular surface lubricant. Component motion and reaction force outputs were collected from the knee simulator and compared against the kinematic targets of the design in order to validate the surface-guided knee concept.


The Bone & Joint Journal
Vol. 103-B, Issue 4 | Pages 627 - 634
1 Apr 2021
Sabah SA Alvand A Beard DJ Price AJ

Aims

To estimate the measurement properties for the Oxford Knee Score (OKS) in patients undergoing revision knee arthroplasty (responsiveness, minimal detectable change (MDC-90), minimal important change (MIC), minimal important difference (MID), internal consistency, construct validity, and interpretability).

Methods

Secondary data analysis was performed for 10,727 patients undergoing revision knee arthroplasty between 2013 to 2019 using a UK national patient-reported outcome measure (PROM) dataset. Outcome data were collected before revision and at six months postoperatively, using the OKS and EuroQol five-dimension score (EQ-5D). Measurement properties were assessed according to COnsensus-based Standards for the selection of health status Measurement Instruments (COSMIN) guidelines.


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.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_1 | Pages 58 - 58
1 Feb 2021
Sires J Wilson C
Full Access

Robotic-assisted technology in total knee arthroplasty (TKA) aims to increase implantation accuracy, with real-time data being used to estimate intraoperative component alignment. Postoperatively, Perth computed tomography (CT) protocol is a valid measurement technique in determining both femoral and tibial component alignments. The aim of this study was to evaluate the accuracy of intraoperative component alignment by robotic-assisted TKA through CT validation. A total of 33 patients underwent TKA using the MAKO robotic-assisted TKA system. Intraoperative measurements of both femoral and tibial component placements, as well as limb alignment as determined by the MAKO software were recorded. Independent postoperative Perth CT protocol was obtained (n.29) and compared with intraoperative values. Mean absolute difference between intraoperative and postoperative measurements for the femoral component were 1.17 degrees (1.10) in the coronal plane, 1.79 degrees (1.12) in the sagittal plane, and 1.90 degrees (1.88) in the transverse plane. Mean absolute difference between intraoperative and postoperative measurements for the tibial component were 1.03 degrees (0.76) in the coronal plane and 1.78 degrees (1.20) in the sagittal plane. Mean absolute difference of limb alignment was 1.29 degrees (1.25), with 93.10% of measurements within 3 degrees of postoperative CT measurements. Overall, intraoperatively measured component alignment as estimated by the MAKO robotic-assisted TKA system is comparable to CT-based measurements.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_11 | Pages 44 - 44
1 Dec 2020
Torgutalp ŞŞ Korkusuz F
Full Access

Background

Although there are predictive equations that estimate the total fat mass obtained from multiple-site ultrasound (US) measurements, the predictive equation of total fat mass has not been investigated solely from abdominal subcutaneous fat thickness. Therefore, the aims of this study were; (1) to develop regression-based prediction equations based on abdominal subcutaneous fat thickness for predicting fat mass in young- and middle-aged adults, and (2) to investigate the validity of these equations to be developed.

Methods

The study was approved by the Local Research Ethics Committee (Decision number: GO 19/788). Twenty-seven males (30.3 ± 8.7 years) and eighteen females (32.4 ± 9.5 years) were randomly divided into two groups as the model prediction group (19 males and 12 females) and the validation group (8 males and 6 females). Total body fat mass was determined by dual-energy X-ray absorptiometry (DXA). Abdominal subcutaneous fat thickness was measured by US. The predictive equations for total fat mass from US were determined as fat thickness (in mm) × standing height (in m). Statistical analyses were performed using R version 4.0.0. The association between the total fat mass and the abdominal subcutaneous fat thickness was interpreted using the Pearson test. The linear regression analysis was used to predict equations for total body fat mass from the abdominal subcutaneous fat thickness acquired by US. Then these predictive equations were applied to the validation group. The paired t-test was used to examine the difference between the measured and the predicted fat masses, and Lin's concordance correlation coefficient (CCC) was used as a further measure of agreement.


The Bone & Joint Journal
Vol. 102-B, Issue 12 | Pages 1599 - 1607
1 Dec 2020
Marson BA Craxford S Deshmukh SR Grindlay DJC Manning JC Ollivere BJ

Aims

This study evaluates the quality of patient-reported outcome measures (PROMs) reported in childhood fracture trials and recommends outcome measures to assess and report physical function, functional capacity, and quality of life using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) standards.

Methods

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-compliant systematic review of OVID Medline, Embase, and Cochrane CENTRAL was performed to identify all PROMs reported in trials. A search of OVID Medline, Embase, and PsycINFO was performed to identify all PROMs with validation studies in childhood fractures. Development studies were identified through hand-searching. Data extraction was undertaken by two reviewers. Study quality and risk of bias was evaluated by COSMIN guidelines and recorded on standardized checklists.