Aims

The aim of this study was to investigate whether wear and backside deformation of polyethylene (PE) tibial inserts may influence the cement cover of tibial trays of explanted total knee arthroplasties (TKAs).

Aims

The aim of this study is to develop a core set of outcome domains that should be considered and reported in all future trials of childhood limb fractures.

Aims. Various radiological parameters are used to evaluate a flatfoot deformity and their measurements may differ. The aims of this study were to answer the following questions: 1) Which of the 11 parameters have the best inter- and intraobserver reliability in a standardized radiological setting? 2) Are pre- and postoperative assessments equally reliable? 3) What are the identifiable sources of variation?. Patients and Methods. Measurements of the 11 parameters were recorded on anteroposterior and lateral weight-bearing radiographs of 38 feet before and after surgery for flatfoot, by three observers with different experience in foot surgery (A, ten years; B, three years; C, third-year orthopaedic resident). The inter- and intraobserver reliability was calculated. Results. Preoperative interobserver reliability was high for four, moderate for five, and low for two parameters. Postoperative interobserver reliability was high for four, moderate for five, and low for two parameters. Intraobserver reliability was excellent for all parameters preoperatively as recorded by observer A (PB) and B (MP), and for eight parameters as recorded by observer C (SR). Intraobserver reliability was excellent for ten parameters postoperatively as recorded by observer A and B, and for eight parameters as recorded by observer C. Conclusion. The following parameters can be recommended. For preoperative and postoperative evaluation of flatfoot: anteroposterior, talonavicular coverage angle; lateral, talometatarsal I angle, calcaneal pitch angle, and cuneiform-medial height (high interobserver reliability); and anteroposterior, talometatarsal II angle; lateral, talocalcaneal angle,tibiocalcaneal angle (moderate interobserver reliability). For more experienced observers, we also recommend the anteroposterior talometatarsal I angle (moderate reliability). The inter- and intraobserver reliability for most parameters were similar pre- and postoperatively. The experience of the observer and the definition and ability to measure the parameters themselves were sources of variation. Cite this article: Bone Joint J 2018;100-B:596–602

Aims

To fully verify the reliability and reproducibility of an experimental method in generating standardized micromotion for the rat femur fracture model.

Objectives. To validate the precision of digitally reconstructed radiograph (DRR) radiostereometric analysis (RSA) and the model-based method (MBM) RSA with respect to benchmark marker-based (MM) RSA for evaluation of kinematics in the native hip joint. Methods. Seven human cadaveric hemipelves were CT scanned and bone models were segmented. Tantalum beads were placed in the pelvis and proximal femoral bone. RSA recordings of the hips were performed during flexion, adduction and internal rotation. Stereoradiographic recordings were all analyzed with DRR, MBM and MM. Migration results for the MBM and DRR with respect to MM were compared. Precision was assessed as systematic bias (mean difference) and random variation (Pitman’s test for equal variance). Results. A total of 288 dynamic RSA images were analyzed. Systematic bias for DRR and MBM with respect to MM in translations (p < 0.018 mm) and rotations (p < 0.009°) were approximately 0. Pitman’s test showed lower random variation in all degrees of freedom for DRR compared with MBM (p < 0.001). Conclusion. Systematic error was approximately 0 for both DRR or MBM. However, precision of DRR was statistically significantly better than MBM. Since DRR does not require marker insertion it can be used for investigation of preoperative hip kinematics in comparison with the postoperative results after joint preserving hip surgery. . Cite this article: L. Hansen, S. De Raedt, P. B. Jørgensen, B. Mygind-Klavsen, B. Kaptein, M. Stilling. Marker free model-based radiostereometric analysis for evaluation of hip joint kinematics: A validation study. Bone Joint Res 2018;7:379–387. DOI: 10.1302/2046-3758.76.BJR-2017-0268.R1

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The number of convolutional neural networks (CNN) available for fracture detection and classification is rapidly increasing. External validation of a CNN on a temporally separate (separated by time) or geographically separate (separated by location) dataset is crucial to assess generalizability of the CNN before application to clinical practice in other institutions. We aimed to answer the following questions: are current CNNs for fracture recognition externally valid?; which methods are applied for external validation (EV)?; and, what are reported performances of the EV sets compared to the internal validation (IV) sets of these CNNs?

Aims. It is important to consider sagittal pelvic rotation when introducing the acetabular component at total hip arthroplasty (THA). The purpose of this study was to identify patients who are at risk of unfavourable pelvic mobility, which could result in poor outcomes after THA. Patients and Methods. A consecutive series of 4042 patients undergoing THA had lateral functional radiographs and a low-dose CT scan to measure supine pelvic tilt, pelvic incidence, standing pelvic tilt, flexed-seated pelvic tilt, standing lumbar lordotic angle, flexed-seated lumbar lordotic angle, and lumbar flexion. Changes in pelvic tilt from supine-to-standing positions and supine-to-flexed-seated positions were determined. A change in pelvic tilt of 13° between positions was deemed unfavourable as it alters functional anteversion by 10° and effectively places the acetabular component outside the safe zone of orientation. Results. For both men and women, the degree of lumbar flexion was a significant predictor of risk in hip flexion (p < 0.0001) with increased odds of unfavourable pelvic mobility in those with lumbar flexion of < 20° (men, odds ratio (OR) 6.74, 95% confidence interval (CI) 3.83 to 11.89; women, OR 2.97, 95% CI 1.87 to 4.71). In women, age and standing pelvic tilt were significant predictors of risk in hip extension (p = 0.0082 and p < 0.0001, respectively). The risk of unfavourable pelvic mobility was higher in those aged > 75 years (OR 2.28, 95% CI 1.56 to 3.32) and those with standing pelvic tilt of < -10° for extension risk (OR 7.10, 95% CI 4.10 to 10.29). In men, only standing pelvic tilt was significant (p < 0.0001) for hip extension with an increased risk of unfavourable pelvic mobility (OR 8.68, 95% CI 5.19 to 14.51). Conclusion. Patients found to have unfavourable pelvic mobility had limited lumbar flexion and more posterior standing pelvic tilt in both men and women, as well as increasing age in women. We recommend that patients undergo preoperative functional radiographic screening to determine specific parameters that can affect the functional orientation of the acetabular component. Cite this article: Bone Joint J 2018;100-B:845–52

Aims. The significance of the ‘clicky hip’ in neonatal and infant examination remains controversial with recent conflicting papers reigniting the debate. We aimed to quantify rates of developmental dysplasia of the hip (DDH) in babies referred with ‘clicky hips’ to our dedicated DDH clinic. Patients and Methods. A three-year prospective cohort study was undertaken between 2014 and 2016 assessing the diagnosis and treatment outcomes of all children referred specifically with ‘clicky hips’ as the primary reason for referral to our dedicated DDH clinic. Depending on their age, they were all imaged with either ultrasound scan or radiographs. Results. There were 69 ‘clicky hip’ referrals over the three-year period. This represented 26.9% of the total 257 referrals received in that time. The mean age at presentation was 13.6 weeks (1 to 84). A total of 19 children (28%) referred as ‘clicky hips’ were noted to have hip abnormalities on ultrasound scan, including 15 with Graf Type II hips (7 bilateral), one Graf Type III hip, and three Graf Type IV hips. Of these, ten children were treated with a Pavlik harness, with two requiring subsequent closed reduction in theatre; one child was treated primarily with a closed reduction and adductor tenotomy. In total, 11 (15.9%) of the 69 ‘clicky hip’ referrals required intervention with either harness or surgery. Conclusion. Our study provides further evidence that the ‘clicky hip’ referral can represent an underlying diagnosis of DDH and should, in our opinion, always lead to further clinical and radiological assessment. In the absence of universal ultrasound screening, we would encourage individual units to carefully assess their own outcomes and protocols for ‘clicky hip’ referrals and tailor ongoing service provision to local populations and local referral practices. Cite this article: Bone Joint J 2018;100-B:1249–52

Aims. The aim of this study was to present a series of patients with aseptic failure of a total ankle arthroplasty (TAA) who were treated with fusion of the hindfoot using a nail. Patients and Methods. A total of 23 TAAs, in 22 patients, were revised for aseptic loosening and balloon osteolysis to a hindfoot fusion by a single surgeon (NH) between January 2012 and August 2014. The procedure was carried out without bone graft using the Phoenix, Biomet Hindfoot Arthrodesis Nail. Preoperative investigations included full blood count, CRP and ESR, and radiological investigations including plain radiographs and CT scans. Postoperative plain radiographs were assessed for fusion. When there was any doubt, CT scans were performed. Results. The mean follow-up was 13.9 months (4.3 to 37.2). Union occurred at the tibiotalar joint in 22 ankles (95.6%) with one partial union. Union occurred at the subtalar joint in 20 ankles (87%) of cases with two nonunions. The nail broke in one patient with a subtalar nonunion and revision was undertaken. The only other noted complication was one patient who suffered a stress fracture at the proximal aspect of the nail, which was satisfactorily treated conservatively. Conclusion. This study represents the largest group of patients reported to have undergone revision TAA to fusion of the hindfoot with good results. Cite this article: Bone Joint J 2018;100-B:475–9

Aims

Varus-valgus constrained (VVC) devices are typically used in revision settings, often with stems to mitigate the risk of aseptic loosening. However, in at least one system, the VVC insert is compatible with the primary posterior-stabilized (PS) femoral component, which may be an option in complex primary situations. We sought to determine the implant survivorship, radiological and clinical outcomes, and complications when this VVC insert was coupled with a PS femur without stems in complex primary total knee arthroplasties (TKAs).

Aims. Accurate placement of the acetabular component is essential in total hip arthroplasty (THA). The purpose of this study was to determine if the ability to achieve inclination of the acetabular component within the ‘safe-zone’ of 30° to 50° could be improved with the use of an inclinometer. Patients and Methods. We reviewed 167 primary THAs performed by a single surgeon over a period of 14 months. Procedures were performed at two institutions: an inpatient hospital, where an inclinometer was used (inclinometer group); and an ambulatory centre, where an inclinometer was not used as it could not be adequately sterilized (control group). We excluded 47 patients with a body mass index (BMI) of > 40 kg/m. 2. , age of > 68 years, or a surgical indication other than osteoarthritis whose treatment could not be undertaken in the ambulatory centre. There were thus 120 patients in the study, 68 in the inclinometer group and 52 in the control group. The inclination angles of the acetabular component were measured from de-identified plain radiographs by two blinded investigators who were not involved in the surgery. The effect of the use of the inclinometer on the inclination angle was determined using multivariate regression analysis. Results. The mean inclination angle for the THAs in the inclinometer group was 42.9° (95% confidence interval (CI) 41.7° to 44.0°; range 29.0° to 63.8°) and 46.5° (95% CI 45.2° to 47.7°; range 32.8° to 63.2°) in the control group (p < 0.001). Regression analysis identified a 9.1% difference in inclination due to the use of an inclinometer (p < 0.001), and THAs performed without the inclinometer were three times more likely to result in inclination angles of > 50° (odds ratio (OR) 2.8, p = 0.036). The correlation coefficient for the interobserver reliability of the measurement of the two investigators was 0.95 (95% CI 0.93 to 0.97). Conclusion. The use of a simple inclinometer resulted in a significant reduction in the number of outliers compared with a freehand technique. Cite this article: Bone Joint J 2018;100-B:862–6

There is increasing popularity in the use of artificial intelligence and machine-learning techniques to provide diagnostic and prognostic models for various aspects of Trauma & Orthopaedic surgery. However, correct interpretation of these models is difficult for those without specific knowledge of computing or health data science methodology. Lack of current reporting standards leads to the potential for significant heterogeneity in the design and quality of published studies. We provide an overview of machine-learning techniques for the lay individual, including key terminology and best practice reporting guidelines.

Cite this article: Bone Joint J 2021;103-B(12):1754–1758.

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Bone marrow-derived mesenchymal stem cells obtained from bone marrow aspirate concentrate (BMAC) with platelet-rich plasma (PRP), has been used as an adjuvant to hip decompression. Early results have shown promise for hip preservation in patients with osteonecrosis (ON) of the femoral head. The purpose of the current study is to examine the mid-term outcome of this treatment in patients with precollapse corticosteroid-induced ON of the femoral head.

Aims

The effect of pelvic tilt (PT) and sagittal balance in hips with pincer-type femoroacetabular impingement (FAI) with acetabular retroversion (AR) is controversial. It is unclear if patients with AR have a rotational abnormality of the iliac wing. Therefore, we asked: are parameters for sagittal balance, and is rotation of the iliac wing, different in patients with AR compared to a control group?; and is there a correlation between iliac rotation and acetabular version?

Objectives. Current studies on the additional benefit of using computed tomography (CT) in order to evaluate the surgeons’ agreement on treatment plans for fracture are inconsistent. This inconsistency can be explained by a methodological phenomenon called ‘spectrum bias’, defined as the bias inherent when investigators choose a population lacking therapeutic uncertainty for evaluation. The aim of the study is to determine the influence of spectrum bias on the intra-observer agreement of treatment plans for fractures of the distal radius. Methods. Four surgeons evaluated 51 patients with displaced fractures of the distal radius at four time points: T1 and T2: conventional radiographs; T3 and T4: radiographs and additional CT scan (radiograph and CT). Choice of treatment plan (operative or non-operative) and therapeutic certainty (five-point scale: very uncertain to very certain) were rated. To determine the influence of spectrum bias, the intra-observer agreement was analysed, using Kappa statistics, for each degree of therapeutic certainty. . Results. In cases with high therapeutic certainty, intra-observer agreement based on radiograph was almost perfect (0.86 to 0.90), but decreased to moderate based on a radiograph and CT (0.47 to 0.60). In cases with high therapeutic uncertainty, intra-observer agreement was slight at best (-0.12 to 0.19), but increased to moderate based on the radiograph and CT (0.56 to 0.57). Conclusion. Spectrum bias influenced the outcome of this agreement study on treatment plans. An additional CT scan improves the intra-observer agreement on treatment plans for a fracture of the distal radius only when there is therapeutic uncertainty. Reporting and analysing intra-observer agreement based on the surgeon’s level of certainty is an appropriate method to minimise spectrum bias. Cite this article: Bone Joint Res 2015;4:190–194

Objectives. Bone fracture healing is regulated by a series of complex physicochemical and biochemical processes. One of these processes is bone mineralization, which is vital for normal bone development. Phosphatase, orphan 1 (PHOSPHO1), a skeletal tissue-specific phosphatase, has been shown to be involved in the mineralization of the extracellular matrix and to maintain the structural integrity of bone. In this study, we examined how PHOSPHO1 deficiency might affect the healing and quality of fracture callus in mice. Methods. Tibial fractures were created and then stabilized in control wild-type (WT) and Phospho1. -/-. mice (n = 16 for each group; mixed gender, each group carrying equal number of male and female mice) at eight weeks of age. Fractures were allowed to heal for four weeks and then the mice were euthanized and their tibias analyzed using radiographs, micro-CT (μCT), histology, histomorphometry and three-point bending tests. Results. The μCT and radiographic analyses revealed a mild reduction of bone volume in Phospho1. -/-. callus, although it was not statistically significant. An increase in trabecular number and a decrease in trabecular thickness and separation were observed in Phospho1. -/-. callus in comparison with the WT callus. Histomorphometric analyses showed that there was a marked increase of osteoid volume over bone volume in the Phospho1. -/-. callus. The three-point bending test showed that Phospho1. -/-. fractured bone had more of an elastic characteristic than the WT bone. Conclusion. Our work suggests that PHOSPHO1 plays an integral role during bone fracture repair and may be a therapeutic target to improve the fracture healing process. Cite this article: M. W. Morcos, H. Al-Jallad, J. Li, C. Farquharson, J. L. Millán, R. C. Hamdy, M. Murshed. PHOSPHO1 is essential for normal bone fracture healing: An Animal Study. Bone Joint Res 2018;7:397–405. DOI: 10.1302/2046-3758.76.BJR-2017-0140.R2

Aims. We report the clinical results of glenoid osteotomy in patients with atraumatic posteroinferior instability associated with glenoid dysplasia. Patients and Methods. The study reports results in 211 patients (249 shoulders) with atraumatic posteroinferior instability. The patients comprised 63 men and 148 women with a mean age of 20 years. The posteroinferior glenoid surface was elevated by osteotomy at the scapular neck. A body spica was applied to maintain the arm perpendicular to the glenoid for two weeks postoperatively. Clinical results were evaluated using the Rowe score and Japan Shoulder Society Shoulder Instability Score (JSS-SIS); bone union, osteoarthrosis, and articular congruity were examined on plain radiographs. Results. The Rowe score improved from 36 to 88 points, and the JSS-SIS improved from 47 to 81 points. All shoulders exhibited union without progression of osteoarthritis except one shoulder, which showed osteoarthritic change due to a previous surgery before the glenoid osteotomy. All but three shoulders showed improvement in joint congruency. Eight patients developed disordered scapulohumeral rhythm during arm elevation, and 12 patients required additional open stabilization for anterior instability. Conclusion. Good results can be expected from glenoid osteotomy in patients with atraumatic posteroinferior instability associated with glenoid dysplasia. Cite this article: Bone Joint J 2018;100-B:331–7