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Approximately 60,000 cemented femoral stems are implanted in the UK each year with the majority being manufactured from stainless steel containing 10–15% nickel. Nickel hypersensitivity has been reported in up to 13% of the general population and there is a concern that nickel hypersensitivity might adversely affect the outcome of total hip replacement (THR). We reviewed the current literature on the potential link between nickel hypersensitivity and THR complications, and the usefulness of patch testing. We conducted a literature search in PubMed, MEDLINE and EMBASE databases. The level of evidence and the quality of the selected studies were assessed using the Oxford Centre for Evidence-Based Medicine Criteria and the Methodological Index for Non-Randomised Studies tool, respectively. Twenty-six studies met the inclusion criteria, reporting on 1852 patients who underwent primary or revision THR. All studies detailed skin patch testing and recorded prevalence of nickel hypersensitivity from 1.5% to 33.3%. Five studies reported a rise in Nickel hypersensitivity following THR, while four reported a decreased prevalence post-operatively. Eight studies concluded that metal hypersensitivity could have developed following THR, while seven studies did not support a link between metal hypersensitivity and THR complications. Four of the studies recommended routine patch testing pre-operatively, but three others concluded that routine patch testing was not indicated. We have not identified a link between nickel hypersensitivity and THR complications, and the role of patch testing remains unclear. Further large-scale studies would be required to investigate this relationship and to clarify the role of patch testing in facilitating implant selection.Cite this article: EFORT Open Rev 2021;6:825-838. DOI: 10.1302/2058-5241.6.210051

The Oxford Knee Score (OKS) is a patient-reported outcome questionnaire typically used to assess function and pain in patients undergoing total knee replacement (TKR). However, research is inconclusive as to which preoperative factors are important in explaining variation in outcome following TKR. The operative records of 12,709 patients who underwent primary TKR over a 9-year period were analyzed. The following variables were collected for each patient: age, sex, body mass index (BMI), Index of Multiple Deprivation decile rank, side of operation, diagnosis, the American Society of Anaesthesiologists (ASA) grade, preoperative OKS, EQ-5D index score, EuroQol visual analog scale (EQ-VAS) score, the postoperative OKS at 1 and 2 years. Generalized linear regression models were performed at 1 and 2 years to investigate the effect of the preoperative variables on the postoperative OKS. The effect of age, sex, BMI, Index of Multiple Deprivation decile rank, diagnosis, ASA grade, preoperative OKS, EuroQoL five-dimensional (EQ-5D) index score, and EQ-VAS score were all statistically significant in explaining the variation in OKS at 1 and 2 years postoperatively, with critical level of significance of 0.05 (5%). Being male aged 60 to 69 years of normal BMI, ASA grade I (fit and healthy), living in an affluent area, not reporting preoperative anxiety/depression, were associated with an enhanced mean postoperative OKS at both 1 and 2 years. When adjusted for potential confounding, age of 60–69 years, male sex, normal BMI, lower ASA grade, higher Index of Multiple Deprivation and higher pre-operative EQ-5D, EQ-VAS and OKS were identified as factors that resulted in higher post-operative OKS after primary TKR.

The purpose of this study was to compare the accuracy and the inter- and intra-observer reliability of preoperative digital 2D templating in prosthesis size prediction for the planning of cemented or uncemented THA. This study was registered in the NIHR PROSPERO database (ID: CRD42020216649) and conducted according to the PRISMA guidelines. A search of electronic databases in March 2021 found 29 papers overall. The quality of evidence was assessed using the IHE Quality Appraisal of Case Series Studies Checklist and the CASP Randomised Controlled Trials Checklist. A meta-analysis was conducted, and the accuracy was presented as proportions and the inter- and intra-observer reliability were measured using intraclass correlation coefficients (ICC). Accuracy within one prosthesis size (±1) for cemented stems was 0.89 (95% confidence interval (CI) 0.83–0.95), cemented cups 0.78 (95% CI 0.67–0.89), uncemented stems 0.74 (95% CI 0.66–0.82) and uncemented cups 0.73 (95% CI 0.67–0.79) (test of group differences: p = 0.010). Inter-observer reliability (ICC) for uncemented cups was 0.88 (95% CI 0.85–0.91), uncemented stems 0.86 (95% CI 0.81–0.91), cemented stems 0.69 (95% CI 0.54–0.84) and cemented cups 0.68 (95% CI 0.55–0.81) (test of group differences: p = 0.004). Due to lack of data, intra-observer reliability (ICC) could only be calculated for uncemented prostheses, which for the stems was 0.90 (95% CI 0.88–0.92) and for the cups was 0.87 (95% CI 0.83–0.90) (test of group differences: p = 0.124). The accuracy of preoperative digital templating is greater for cemented prostheses, but the inter-observer reliability is greater for uncemented prostheses. The intra-observer reliability showed a high level of agreement for uncemented prostheses. Cite this article: EFORT Open Rev 2021;6:1020-1039. DOI: 10.1302/2058-5241.6.210048

Arthroscopic procedures to treat hip pathologies such as femoroacetabular impingement (FAI) syndrome are now established in mainstream orthopaedic practice. Surgical techniques, rehabilitation protocols and outcomes are widely published. However, consensus on standards of practice remains to be determined. The International Hip Preservation Society (ISHA) has undertaken a research study to identify current areas of consensus across the global hip preservation community. The study focussed on consensus statements on the operative steps in the arthroscopic treatment of FAI syndrome. The study methodology was an online Delphi consensus method to collect aggregate opinions from hip preservation surgeons worldwide. Phase 1 of the planned three-phase study is presented here—focusing on consensus statements on the operative steps in the arthroscopic treatment of FAI syndrome. Ninety-nine statements achieved >80% consensus from a panel of 165 surgeons from six continents. This study is the first to evaluate global consensus on the arthroscopic treatment of FAI syndrome, as well as highlighting areas of contention and avenues for future research.

Introduction: Instability accounts for 1/3 of revision total hip arthroplasty (rTHA) performed in the UK. Removal of well-fixed femoral stems in rTHA is challenging with a risk of blood loss and iatrogenic damage to the femur. The Bioball universal adaptor (BUA), a modular head neck extension adaptor, provides a mechanism for optimisation of femoral offset, leg length and femoral anteversion. This can avoid the need for femoral stem revision in selected cases. The aim of this study is to present the clinical results and rate of instability following revision with this BUA at a minimum of 2 years follow-up. Patients and methods: A review of our prospectively collected database was performed. All patients treated with the Bioball device were included. Clinical and radiologic review were performed pre- and post-surgery. Specific enquiry for instability was made. The Oxford Hip Score (OHS), EuroQol (EQ-5D) score and WOMAC scores were calculated pre-and post-operatively. Complications were recorded. Results: 32 rTHA procedures were performed using the Bioball device between 2013 and 2016. 4 patients did not wish to complete post-operative questionnaires. 2 patients (2/28, 7%) complained of recurrent dislocations following their rTHA procedure. 1 patient complained of instability but no dislocation. The median pre-operative EQ-5D was 0.195 (range −0.07–0.85), OHS was 20 (range 5–43) and WOMAC was 29.8 (range 15.5–52.3). The median EQ-5D was 0.85 (range 0.59–1), OHS was 39 (range 21–48) and WOMAC was 91.1 (range 44.5–99.2) at final follow-up. There were significant improvements in the EQ-5D ( p = 0.0009), OHS ( p = 0.0004) and WOMAC ( p = 0.0001). Conclusion: The BUA is associated with significant functional improvement and relatively low dislocation rates in revision THA. It is a viable option for use in the revision setting.

Background: Polycarbonate urethane (PCU) is a bearing surface with a lower modulus of elasticity than polyethylene or ceramic and is thought to more closely replicate the tribology of native hyaline cartilage. The purpose of this study was to determine the clinical outcomes with the use of PCU in elective total hip arthroplasty (THA). Methods: We carried out a prospective observational study in which 157 patients underwent elective THA with a metal-on-PCU hip system. Patients had radiographic follow-up at 6 months and 3 years after surgery. Oxford Hip Scores and EuroQol scores were obtained annually and Harris Hip Scores were obtained at 6 months and 3 years after surgery. Results: 180 hips were implanted, of which, 149 hips reached 3-year review with no revisions. There was an increase in Harris Hip Scores, Oxford Hip Scores and EuroQol scores ( p < 0.001). 12 patients (12 hips) reported painless hip squeaking. There were no dislocations and no other adverse events were reported. Conclusion: Our results showed satisfactory survivorship and improvements in patient reported outcomes with metal on PCU THA. Long-term data are still being collected to confirm these findings. We recommend further tribological research into the squeaking phenomenon we observed.

Aims The primary aim of this study was to assess whether the postoperative Oxford Knee Score (OKS) demonstrated a ceiling effect at one and/or two years after total knee arthroplasty (TKA). The secondary aim was to identify preoperative independent predictors for patients that achieved a ceiling score after TKA. Methods A retrospective cohort of 5,857 patients undergoing a primary TKA were identified from an established arthroplasty database. Patient demographics, body mass index (BMI), OKS, and EuroQoL five-dimension (EQ-5D) general health scores were collected preoperatively and at one and two years postoperatively. Logistic regression analysis was used to identify independent preoperative predictors of patients achieving postoperative ceiling scores. Receiver operating characteristic curve was used to identify a preoperative OKS that predicted a postoperative ceiling score. Results The ceiling effect was 4.6% (n = 272) at one year which increased significantly (odds ratio (OR) 40.3, 95% confidence interval (CI) 30.4 to 53.3; p < 0.001) to 6.2% (n = 363) at two years, when defined as those with a maximal score of 48 points. However, when the ceiling effect was defined as an OKS of 44 points or more, this increased to 26.3% (n = 1,540) at one year and further to 29.8% (n = 1,748) at two years (OR 21.6, 95% CI 18.7 to 25.1; p < 0.001). A preoperative OKS of 23 or more and 22 or more were predictive of achieving a postoperative ceiling OKS at one and two years when defined as a maximal score or a score of 44 or more, respectively. Conclusion The postoperative OKS demonstrated a small ceiling effect when defined by a maximal score, but when defined by a postoperative OKS of 44 or more the ceiling effect was moderate and failed to meet standards. The preoperative OKS was an independent predictor of achieving a ceiling score. Cite this article: Bone Joint J 2020;102-B(11):1519–1526.

Background The Medial Rotation Knee (MRK) has one of the lowest revision rates of total knee replacement designs in the National Joint Registry. While survival is one metric of performance of implants, patient-reported outcomes, combined with clinical and radiological evaluation, allow more complete analysis. We report the five-year results of a prospective, multi-centre surveillance study of the MRK. Methods A 16-surgeon, three-centre series of 520 total knee replacements were performed in 486 patients, comprising 182 males and 304 females. The mean age was 70.3 years (46–96) and BMI 29.5 kg/m2 (18–57). Study subjects were given questionnaires pre-operatively, at six months, and annually thereafter. Clinical and radiological reviews were scheduled pre-operatively, at six months, three and five years. Results At five years, 395 of the original 486 patients (427 of 520 knees) remained under active review. Twenty-six patients (27 knees) had withdrawn, 44 patients/knees had died and one was excluded. Thirteen patients (14 knees) were lost to follow-up, but were not revised. Seven knees were revised, equating to a survival probability of 98.6% at five years. There were significant improvements in mean Oxford Knee Score (21.23–35.79), EQ-5D (0.440–0.694) and Knee Society Score (Knee 43.00–83.97; Function 49.45–71.39). Of the radiographs available for evaluation, radiolucency was identified in 25 knees (14.6%) with one case of osteolysis of the tibial component. Conclusion In addition to excellent survivorship, mid-term patient-reported, clinical and radiological results at five years are satisfactory, and consistent with other medial pivot designs.

The aim was to assess the whether there was a clinically important change in the Oxford knee score (OKS) between one and two years after total knee arthroplasty (TKA), and to identify predictors associated with a clinically important change.A retrospective cohort study was undertaken using an established arthroplasty database of 5857 primary TKA. Patient demographics, body mass index, social deprivation, OKS and EuroQoL five-domain (EQ-5D) score were collected preoperatively and at one and two years postoperatively. A clinically important change in the OKS was defined as ≥5 points.There was a 0.2 point increase in the OKS between one and two years, which was statistically significant (95% confidence interval (CI) 0.1 to 0.4, p .0001), but not clinically important. A better preoperative OKS (p .001) and in contrast a worse one year OKS (p .001) were independently associated with a greater improvement from one to two years. There were 1006 (17.3%) patients that had a clinically important improvement in the OKS between one and two years. Receiver operating characteristic curve analysis showed that a one year OKS of less than 35 was a reliable predictor of a clinically important improvement between one and two years (area under the curve 0.77, 95% CI 0.76 to 0.78, p .001).There was not a clinically important change in the OKS from one to two years after TKA when assessed as a group. However, individual patients with a one year OKS of less than 35 may demonstrate a clinically important improvement at two years.Retrospective diagnostic study, Level III.

Background With over 2.35 million records, the National Joint Registry (NJR) is the largest arthroplasty registry in the world. It provides a powerful tool to monitor implant survivorship and influence different surgical strategies. To date, little work has been undertaken to investigate the validity of the ‘Reason for Revision’ recorded in Consultant Outcome Reports on the NJR. Methods The NJR was queried to identify all revisions on the THR performed at a single centre over an 11-year period. Review and validation of ‘Reason for Revision’ for each case was undertaken using radiological imaging studies, pathology, histology, microbiology and electronic medical records. Results Of the 22,046 primary total hip replacements (THR) and total knee replacements (TKR) undertaken by 23 surgeons at our hospital, over an 11-year period, 1.35% (297) were subsequently reported to the NJR as revised. Discrepancies in reporting to the NJR were identified for 41 cases (25.63%) for THR and 28 (20.40%) cases for TKR. Revision for infection was under-reported for both THR and TKR by 1.88% and 3.65% respectively. Reporting of adverse soft tissue reaction to particulate debris for THR was unreported by 11%. Progressive arthritis following a TKR was unreported by 6.56%. All the cases reported as ‘other’ (8.75% for THRs and 3.65% for TKRs) were reclassified to the most appropriate ‘reason for revision’ category. The ‘reason for revision’ data is recorded to the NJR with findings at the time of surgery. It is some days before microbiology and histology reports become available and source data is not always updated. Conclusion If an average of 23% wrong data entry at a highly organised institution is replicated throughout the UK, a formal process to validate primary and revision data submitted to the NJR should be considered. Local scrutiny, review and validation of revision data are all vital to optimise the value of the NJR. Accurate data recorded to the NJR is imperative to provide safe and effective improvements in orthopaedic surgery.

Background\ud Femoroacetabular impingement syndrome is an important cause of hip pain in young adults. It can be treated by arthroscopic hip surgery, including reshaping the hip, or with physiotherapist-led conservative care. We aimed to compare the clinical effectiveness of hip arthroscopy with best conservative care.\ud \ud Methods\ud UK FASHIoN is a pragmatic, multicentre, assessor-blinded randomised controlled trial, done at 23 National Health Service hospitals in the UK. We enrolled patients with femoroacetabular impingement syndrome who presented at these hospitals. Eligible patients were at least 16 years old, had hip pain with radiographic features of cam or pincer morphology but no osteoarthritis, and were believed to be likely to benefit from hip arthroscopy. Patients with bilateral femoroacetabular impingement syndrome were eligible; only the most symptomatic hip was randomly assigned to treatment and followed-up. Participants were randomly allocated (1:1) to receive hip arthroscopy or personalised hip therapy (an individualised, supervised, and progressive physiotherapist-led programme of conservative care). Randomisation was stratified by impingement type and recruiting centre and was done by research staff at each hospital, using a central telephone randomisation service. Patients and treating clinicians were not masked to treatment allocation, but researchers who collected the outcome assessments and analysed the results were masked. The primary outcome was hip-related quality of life, as measured by the patient-reported International Hip Outcome Tool (iHOT-33) 12 months after randomisation, and analysed in all eligible participants who were allocated to treatment (the intention-to-treat population).\ud \ud This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN64081839, and is closed to recruitment. Findings Between July 20, 2012, and July 15, 2016, we identified 648 eligible patients and recruited 348 participants: 171 participants were allocated to receive hip arthroscopy and 177 to receive personalised hip therapy. Three further patients were excluded from the trial after randomisation because they did not meet the eligibility criteria. Follow-up at the primary outcome assessment was 92% (319 of 348 participants). At 12 months after randomisation, mean iHOT-33 scores had improved from 39·2 (SD 20·9) to 58·8 (27·2) for participants in the hip arthroscopy group, and from 35·6 (18·2) to 49·7 (25·5) in the personalised hip therapy group. In the primary analysis, the mean difference in iHOT-33 scores, adjusted for impingement type, sex, baseline iHOT-33 score, and centre, was 6·8 (95% CI 1·7–12·0) in favour of hip arthroscopy (p=0·0093). This estimate of treatment effect exceeded the minimum clinically important difference (6·1 points). There were 147 patient-reported adverse events (in 100 [72%] of 138 patients) in the hip arthroscopy group) versus 102 events (in 88 [60%] of 146 patients) in the personalised hip therapy group, with muscle soreness being the most common of these (58 [42%] vs 69 [47%]). There were seven serious adverse events reported by participating hospitals. Five (83%) of six serious adverse events in the hip arthroscopy group were related to treatment, and the one in the personalised hip therapy group was not. There were no treatment-related deaths, but one patient in the hip arthroscopy group developed a hip joint infection after surgery. Interpretation Hip arthroscopy and personalised hip therapy both improved hip-related quality of life for patients with femoroacetabular impingement syndrome. Hip arthroscopy led to a greater improvement than did personalised hip therapy, and this difference was clinically significant. Further follow-up will reveal whether the clinical benefits of hip arthroscopy are maintained and whether it is cost effective in the long term.\ud \ud Funding\ud The Health Technology Assessment Programme of the National Institute of Health Research.

Synovial tissue can display an inflammatory response in the presence of OA. There is increasing interest to better understand the role of inflammation in OA, particularly with regard to those who require joint replacement. A systematic review of inflammatory synovitis in OA of literature databases was undertaken from their inception until October 14, 2014. Independent critical appraisal of each study was undertaken using the CASP appraisal tool. From a total of sixty-six identified citations, twenty-three studies were deemed eligible for review. The studies presented moderate to strong methodological quality. Strong correlation was identified between histological and imaging synovitis severity. Correlation was weaker between clinical symptoms and imaging and/or histological synovitis severity. There was little consensus, with regard to expressed cytokines and chemokines at the different stages of OA disease progression. Few studies investigated the influence of inflammatory synovitis on the outcome of major joint replacement. Research into inflammatory synovitis in OA is an emerging field. Longitudinal studies applying proven imaging modalities, histological analysis, and longer follow-up are required in order to further define our understanding of the role of synovitis in the pathogenesis of OA and its effects on outcomes following major joint replacement.

We report the ten-year clinical and radiological outcomes of a novel cannulated, tri-tapered femoral stem, used in primary total hip arthroplasty (110 stems in 98 patients). At ten years, two Tri-taper stems had been revised for infection and dislocation. The mean Oxford Hip Score improved from 13.46 pre-operatively, to 37.04. Radiological analysis revealed radiolucent lines in 57 cases, but none exceeded 2 mm thickness. Stem subsidence was identified in 63 cases, with mean distal tip migration of 3.8 mm. Survivorship with revision for aseptic loosening as the end point was 100% at 10 years. Stem survival with revision for any cause was 98.2% (95% CI, 92.9% to 99.5%). The ten-year results of the Tri-taper stem are comparable to other polished, tapered femoral stems.

This study identifies optimal OKS values that discriminate post-operative (TKA) patient satisfaction and determines the variation in threshold values by patient characteristics and expectations. It is the first to identify patient improvement using measures (PoPC) that account for patient's pre-operative symptom severity. Of 365 primary TKA patients from a London district general hospital 84% were satisfied at 12 and 24 months. Whilst the overall OKS thresholds (follow-up, change, PoPC) were stable at 12 months (31, 11, 39.7%) and 24 months (35, 12, 38.9%), patients who were older (≥75years), were underweight/normal (BMI25), had pre-operative symptom severity (OKS≤15) and expected no pain post-surgery, required a greater (potential) improvement to be classed as satisfied. When reporting good patient outcomes, cohorts should be stratified accordingly.

Patient reported outcome measures (PROMs) are used to gauge clinical performance. The PROMs outcome programme at our centre achieves a preoperative data capture rate of 99%. This falls to 90.6%, 89%, 83% and 79% at the six-week, six-month, one-year and two-year time points, respectively. The study aims were to determine factors associated with patients who did not respond to outcome questionnaires following total hip replacement (THR), and the potential implications this may have when assessing patients following THRs. During the first year of the PROMs programme, 1,322 patients underwent unilateral primary THR at our institution. Of these, 1,311 completed preoperative questionnaires. Thirty-eight patients (2.9%) died within two years of surgery and have been excluded. For the remaining 1,273 patients, we identified those who did not return postoperative questionnaires at each of our review time points. Younger age, lower baseline EQ5D and Oxford Hip scores (OHS) were significantly associated with non-response (p

This study aimed at describing the anatomy of the zona orbicularis (ZO), based on magnetic resonance arthrography (MRA) and magnetic resonance imaging (MRI) scans and to assess the presence of synovial folds in relation to the ZO. A retrospective review was performed using consecutive hip and pelvic MRA and MRI examinations from our institution. We identified 25 normal scans of each variety. Patients were scanned in a neutral hip position and 3D FIESTA sequence images were included in a number of cases. Using electronic callipers, measurements were obtained of the ZO thickness and of the location of the ZO with respect of the femoral head and neck. On MRA, the ZO appeared as a horseshoe in 18/25 patients, being absent anteriorly. On MRI the ZO was less consistent and absent in 12/25 posteriorly, in 8/25 inferiorly and in 2/25 anteriorly. Where present, the ZO usually coincided with the boundary of femoral head sphericity and the narrowest point of the isthmus of the femoral neck. The medial synovial fold was identified in all MRA studies (25/25). The ZO of the hip is most consistently identified when the joint is distended and in approximately 75 % of cases appears as a horseshoe-shaped structure. Superiorly, the ZO is aligned perpendicular to the long axis of the femoral neck. The ZO twists from postero-lateral to antero-medial as it moves inferiorly. Our findings are consistent with the hypothesis that the ZO functions as a ring that resists femoral head distraction and contributes to dynamic circulation of synovial fluid.

Summary Objectives To describe whether body mass index (BMI) is a clinically meaningful predictor of patient reported outcomes following primary total hip replacement (THR) surgery. Design Combined data from prospective cohort studies. We obtained information from four cohorts of patients receiving primary THR for osteoarthritis: Exeter Primary Outcomes Study (EPOS) ( n = 1431); EUROHIP ( n = 1327); Elective Orthopaedic Centre ( n = 2832); and St. Helier ( n = 787). The exposure of interest was pre-operative BMI. Confounding variables included: age, sex, SF-36 mental health, comorbidities, fixed flexion, analgesic use, college education, OA in other joints, expectation of less pain, radiographic K&L grade, ASA grade, years of hip pain. The primary outcome was the Oxford Hip Score (OHS). Regression models describe the association of BMI on outcome adjusting for all confounders. Results For a 5-unit increase in BMI, the attained 12-month OHS decreases by 0.78 points 95%CI (0.27–1.28), P -value 0.001. Compared to people of normal BMI (20–25), those in the obese class II (BMI 35–40) would have a 12-month OHS that is 2.34 points lower. Although statistically significant this effect is small and not clinically meaningful in contrast to the substantial change in OHS seen across all BMI groupings. In obese class II patients achieved a 22.2 point change in OHS following surgery. Conclusions Patients achieved substantial change in OHS after THR across all BMI categories, which greatly outweighs the small difference in attained post-operative score. The findings suggest BMI should not present a barrier to access THR in terms of PROMs.

Femoroacetabular impingement (FAI) is a pathomechanical process by which the human hip can fail. The effect of attenuated cartilage on the kinematics and the pathological bone-to-bone contact of an osteoarthritic hip joint with FAI are still unknown. The current study is aiming to simulate osteoarthritis of a cam-type femoral head with cartilage thinning of varying severity. A three-dimensional model of the left hip joint of a male patient diagnosed with FAI was obtained from preoperative computerised tomography data using density segmentation techniques. The kinematics of FAI was simulated using a finite element method. As the acetabulum and femur came into contact, the penetrations were detected, and the contact constraints were applied according to the penalty constraint enforcement method. The translation and rotation parameters were defined in a single step for each one of three cases: healthy cartilage and 2 mm (one-sided thinning) and 4 mm (two-sided thinning) worn out articular cartilages. The results of the analysis show that thinning of the cartilage at the hip joint adversely affects impingement, as a range of motion decreased with progressive thinning of the articular cartilage. In the presence of attenuated cartilage, equating osteoarthritis, the pathomorphology of the cam lesion, likely determines the extent of damage on the rim of the acetabulum, as well.

The Oxford knee score (OKS) is a validated and widely accepted disease-specific patient-reported outcome measure, but there is limited evidence regarding any long-term trends in the score. We reviewed 5600 individual OKS questionnaires (1547 patients) from a prospectively-collected knee replacement database, to determine the trends in OKS over a ten-year period following total knee replacement. The mean OKS pre-operatively was 19.5 (95% confidence interval (CI) 18.8 to 20.2). The maximum post-operative OKS was observed at two years (mean score 34.4 (95% CI 33.7 to 35.2)), following which a gradual but significant decline was observed through to the ten-year assessment (mean score 30.1 (95% CI 29.1 to 31.1)) (p < 0.001). A similar trend was observed for most of the individual OKS components (p < 0.001). Kneeling ability initially improved in the first year but was then followed by rapid deterioration (p < 0.001). Pain severity exhibited the greatest improvement, although residual pain was reported in over two-thirds of patients post-operatively, and peak improvement in the night pain component did not occur until year four. Post-operative OKS was lower for women (p < 0.001), those aged < 60 years (p < 0.003) and those with a body mass index > 35 kg/m2 (p < 0.014), although similar changes in scores were observed. This information may assist surgeons in advising patients of their expected outcomes, as well as providing a comparative benchmark for evaluating longer-term outcomes following knee replacement. Cite this article: Bone Joint J 2013;95-B:45–51.

The hip joint is encapsulated by a thick, cylindrical, fibrous sleeve. It arises from the outer margin of the acetabulum and inserts into the metaphyseal region of the proximal femur. Reinforced by distinct ligaments, taught at extremes of motion, the capsule functions to constrain the hip joint (Hewitt et al., J Arthroplasty 17:82–9, 2002; Martin et al., Arthroscopy 24:188–95, 2008; Ito et al., J Orthop Res 27:989–95, 2009) and helps maintain joint congruence (Ito et al., J Orthop Res 27:989–95, 2009; Myers et al., Am J Sports Med 39:85S–91S, 2011; Crawford et al., Clin Orthop Relat Res 465:16–22, 2007). A synovial membrane lines the articular surface, and loose connective tissue surrounds the exterior, supporting its vascular supply (Gray’s anatomy, Philadelphia, 1918). Known to have mechanical, proprioceptive, and nociceptive properties, recent work suggests that the capsule also contributes to the stability of the femoral head within the acetabulum (Ito et al., J Orthop Res 27:989–95, 2009) and plays an integral role in circulation of synovial fluid within the joint (Field and Rajakulendran, J Bone Joint Surg Am 93:22–7, 2011).

Circulatory systems enable gaseous, nutrient, and metabolite exchange between intra- and extracellular spaces. Our knowledge of synovial fluid circulation is rudimentary. A model for unidirectional synovial fluid circulation in the hip may provide a mechanism for the passage of synovial fluid from the low-pressure peripheral compartment to the high-pressure central compartment. It is hypothesized that, in addition to its role as a restraint to femoral head distraction, the zona orbicularis also functions as a bellows mechanism, the bellows being driven by flexion and extension of the hip joint. Synovial fluid is pumped from the proximal part of the peripheral compartment to the cotyloid fossa with the transverse ligament acting as a unidirectional valve. From the cotyloid fossa, pulvinar compression drives synovial fluid, via the stellate crease, to the lunate articular surface. A tidal flow occurs across the articular surface with return to the peripheral compartment by labral leakage.

Hip arthroscopy constitutes one of the techniques that the surgeon uses to treat his, or her, patients. In consequence, a hip arthroscopy service is normally offered in parallel with other surgical interventions and the effort that a surgeon commits to this part of their practice will depend upon their desire to sub-specialise in arthroscopic hip surgery. This chapter discusses choice of practice location, the commercial viability of a hip arthroscopy practice, the types of patients that may require treatment, the different healthcare providers who may refer to the practice, communication requirements, strategic links that may be beneficial, options for patient assessment, the requirement for imaging services, the importance of data capture, provision of appropriate operating facilities, patient education and expectations, office staff and billing and the provision of contact numbers for patients and healthcare providers. The recommendations provided in this chapter are primarily intended for surgeons who have recently completed their specialist surgical training in orthopedics, have undertaken one or more fellowships in hip arthroscopy and are looking to establish themselves as a hip surgeon with a special interest in hip arthroscopy.

Summary Objectives There is an increasing movement to collect and report patient reported outcome measures (PROM's) following total hip replacement (THR). In the UK, the procedure specific PROM of choice is the Oxford Hip Score (OHS). It is currently unclear how to use this information to determine outcome following surgery. The aim of this study was to define a threshold for the OHS that is correlated with patient satisfaction. Design Prospective cohort study. Setting A district general hospital (St. Helier Hospital, Carshalton, UK). Participants 799 patients receiving THR from 1995 to 2004. Main outcome measures At 12 and 24 months after surgery patients were asked if they were satisfied with surgery and completed the OHS. Receiver operating characteristic (ROC) analyses were used to identify thresholds of follow-up OHS, which best discriminated patient satisfaction. Analyses were stratified by age, sex, body mass index (BMI), baseline OHS and patient expectations. Results 91.9% of patients were satisfied with THR at 12 months (92.8% at 24 months). Using the ROC technique, the OHS at 12 months associated with patient satisfaction was 38 and at 24 months 33. The OHS at 24 months associated with satisfaction was higher in those with highest tertile of baseline OHS (30, 33, 43 respectively), and lowest tertile of BMI. Conclusions We have identified a value of the OHS that predicts patient satisfaction 12–24 months following THR within a standard clinical setting. However, this threshold is markedly influenced by pre-operative OHS and should be stratified accordingly.

The OHS/OKS are PROMs for assessing symptomatic pain and function following TJA. However, actual change in pre-operative/post-operative scores cannot distinguish patients of varying baseline symptom severity. The percentage of potential change (PoPC) is a simple method that accounts for this, expressing the actual change attained, as a percentage of the potential change possible. Measures are described using OHS/OKS at baseline and 6-months (1784 - TKA, 1523 - THA) from the Elective Orthopaedic Centre. Each method identified different proportions of patients as satisfied and importantly, the measures identified different patients. PoPC overcomes floor and ceiling effects and standardises measures to an easy to interpret -100 to +100 scale. In addition to actual change, we recommend using PoPC to assess the overall outcome of patients.

Surgeons undertaking total hip arthroplasty (THA) routinely perform a distal femoral neck resection. It has been argued that retaining the femoral neck during THA can provide mechanical and biological advantages.The objectives of this study were to review: (1) the current evidence on the advantages of femoral neck preservation during THA and (2) the clinical and radiological outcome of neck-preserving femoral stems.A search of the English-language literature on neck-preserving THA and on the individual neck-preserving implants was performed using PubMed, Ovid SP and Science Direct.Studies have indicated that neck preservation offers superior tri-planar implant stability and allows more accurate restoration of the hip geometry and biomechanics. The trend towards tissue sparing surgery has contributed to the development of bone-conserving short-stem implants that offer variable levels of neck preservation. Despite an initial learning curve, these implants have generated promising early clinical results, with low revision rates and high outcome scores. However, radiological evaluation of some neck-preserving implants has detected a characteristic pattern of proximal femoral bone loss with distal cortical hypertrophy. The long-term implications of this finding are not yet known.Preserving the femoral neck during THA has biomechanical advantages. However, long-term outcome data are needed on neck-preserving femoral stems to evaluate on-going bone remodelling and assess implant performance and survival.

Objective: to identify pre-operative predictors of patient-reported outcomes of primary total knee replacement (TKR) surgery. Methods: the Elective Orthopaedic Centre database is a large prospective cohort of 1991 patients receiving primary TKR in south-west London from 2005 to 2008. The primary outcome is the 6-month post-operative Oxford Knee Score (OKS). To classify whether patients had a clinically important outcome, we calculated a patient acceptable symptom state (PASS) for the 6-month OKS related to satisfaction with surgery. Potential predictor variables were pre-operative OKS, age, sex, BMI, deprivation, surgical side, diagnosis, operation type, American Society of Anesthesiologists grade and EQ5D anxiety/depression. Regression modelling was used to identify predictors of outcome. Results: the strongest determinants of outcome include pre-operative pain/function—those with less severe pre-operative disease obtain the best outcomes; diagnosis in relation to pain outcome—patients with RA did better than those with OA; deprivation—those living in poorer areas had worse outcomes; and anxiety/depression—worse pre-operative anxiety/depression led to worse pain. Differences were observed between predictors of pain and functional outcomes. Diagnosis of RA and anxiety/depression were associated with pain, whereas age and gender were specifically associated with function. BMI was not a clinically important predictor of outcome. Conclusion: this study identified clinically important predictors of attained pain/function post-TKR. Predictors of pain were not necessarily the same as functional outcomes, which may be important in the context of a patient’s expectations of surgery. Other predictive factors need to be identified to improve our ability to recognize patients at risk of poor TKR outcomes

We obtained pre-operative and six-month post-operative Oxford hip (OHS) and knee scores (OKS) for 1523 patients who underwent total hip replacement and 1784 patients who underwent total knee replacement. They all also completed a six-month satisfaction question. Scatter plots showed no relationship between pre-operative Oxford scores and six-month satisfaction scores. Spearman’s rank correlation coefficients were -0.04 (95% confidence interval (CI) -0.09 to 0.01) between OHS and satisfaction and 0.04 (95% CI -0.01 to 0.08) between OKS and satisfaction. A receiver operating characteristic (ROC) curve analysis was used to identify a cut-off point for the pre-operative OHS/OKS that identifies whether or not a patient is satisfied with surgery. We obtained an area under the ROC curve of 0.51 (95% CI 0.45 to 0.56) for hip replacement and 0.56 (95% CI 0.51 to 0.60) for knee replacement, indicating that pre-operative Oxford scores have no predictive accuracy in distinguishing satisfied from dissatisfied patients. In the NHS widespread attempts are being made to use patient-reported outcome measures (PROMs) data for the purpose of prioritising patients for surgery. Oxford hip and knee scores have no predictive accuracy in relation to post-operative patient satisfaction. This evidence does not support their current use in prioritising access to care.

We present a novel arthroscopic-assisted technique to graft chondral defects and subchondral cysts of the acetabular socket using a synthetic osteochondral plug. Four patients with groin pain, solitary cysts in the roof of the acetabulum and radiographic evidence of early osteoarthritis were treated. A bone tunnel was prepared from the region of the iliac crest to the acetabular articular surface. A synthetic osteochondral plug was inserted in an ante-grade fashion and positioned flush with the lunate articular cartilage. The minimum follow-up from surgery was 8 months (mean 10 months, range 8 to 11 months). There were no peri-operative complications related to the procedure. All patients reported an improvement in symptoms and function at the latest follow-up. One of the patients underwent a re-look arthroscopy at 5 months for persistent dull groin and buttock pain. Capsular adhesions of the labrum were identified and released. The mean non-arthritic hip score improved from 53.8 (range 43.8 to 70) pre-operatively to 84.6 (range 78.8 to 87.5) at 6 months. Computed tomography and magnetic resonance imaging at 6 months confirmed the stability of the osteochondral plugs and on-going healing. This procedure offers an arthroscopic means to treat patients with solitary acetabular cysts and may prove effective for chondral grafting of denuded acetabular areas in early to moderate degenerative hip disease.

The human hip is subjected to several hundred million loading cycles during a lifetime. Hip instability and femoro-acetabular impingement cause damage to the rim of the acetabulum. The acetabular rim is a highly specialized structure known as the labro-acetabular complex. A unidirectional flow of synovial fluid has been identified in this region. The synovial fluid circulation is driven by the bellows-like movement of the zona orbicularis and depends on hip flexion and extension. Surgical repair of the damaged labro-acetabular complex should satisfy two goals. First, the labrum should be preserved or reconstructed when possible. Second, the precipitating cause of the labro-acetabular damage must be addressed.

We describe a hip condition with a recognisable pattern of clinical signs and radiological findings thought to result from chronic capsular injury. Between June 2006 and October 2009, ten patients (11 hips), four men and six women, were identified with an abnormality of external rotation at the hip joint. A detailed history and clinical examination was undertaken for each patient. Dynamic magnetic resonance imaging of symptomatic and control hips were evaluated for bony and soft tissue appearances. The relative positions of the femoral head and the acetabulum were assessed through a range of hip rotation. In affected hips, a loss of normal log roll recoil was observed. Three distortions of the iliofemoral ligament were identified on axial MR images; thinning at the lateral insertion of the ligament, attenuation of the iliofemoral ligament most noticeably on maximum external rotation (60°) and the appearance of laxity despite full external rotation. Stability of the hip is dependent on the interaction of bony and soft tissue structures. Hip instability is recognised in dysplasia and is known to lead to premature degeneration of the joint. Chronic capsular injury may destabilise previously asymptomatic hips with subsequent development of pain in young, active patients.

Knee arthroplasties are designed to accommodate flexion, axial rotation and anteroposterior (AP) translation. Axial rotation during extension varies, with some rotating platform devices allowing unrestricted rotation while some conforming fixed-bearing designs almost none. The purpose of this study was to examine in vivo kinematics of a fixed-bearing medial rotation-type arthroplasty (MRK) during weight-bearing activities. Fifteen knees with a medial pivot TKA design were studied during step and pivot activities using lateral fluoroscopy and model-image registration. Average knee kinematics during the step activity showed little AP translation or rotation from 0 degrees -100 degrees flexion. During the pivot activity, the mean tibial internal rotation in individual knees was 7 degrees (3 degrees -19 degrees ). Mean condylar translations for individual knees were 3mm medially and 5mm laterally. The medial pivot prosthesis design provides anteroposterior stability during demanding activities, and exhibits a medial pivot motion pattern when subjected to twisting.

We report the outcome of total hip replacement in 29 failed metal-on-metal resurfacing hip replacements in which the primary surgery was performed between August 1995 and February 2005. The mean length of follow-up was five years (1.7 to 11.7). Of the 29 hip resurfacings, 19 acetabular components and all the femoral components were revised (28 uncemented stems and one cemented stem). There were no deaths and none of the patients was lost to follow-up. None of the hips underwent any further revision. The results of the revision resurfacing group were compared with those of a control group of age-matched patients. In the latter group there were 236 primary total hip replacements and 523 resurfacings performed during the same period by the same surgeons. The outcome of the revision resurfacing group was comparable with that of the stemmed primary hip replacement group but was less good than that of the primary hip resurfacing group. Long-term follow-up is advocated to monitor the outcome of these cases.

Valgus alignment of femoral resurfacing components has been advocated to reduce proximal femur loading and thus minimize the risk for femoral neck fractures. However, such reduction in loading may exacerbate undesirable stress shielding. This study examined the effect of extreme implant orientations (+/-15 degrees ) and stem canal overreaming on initial bone remodeling stimulus using finite element models. The changes in implant-cement interface stresses due to implant alignment were also evaluated. The valgus model showed increased initial bone resorption stimulus, which extended distally and peripherally around the femoral neck. The peak implant-cement interface shear stress for the varus model was 10.9 MPa, exceeding the interface shear strength. Overreaming of the stem canal eliminated distal tip loading, but proximal stress shielding was still unavoidable. These data show bone loading and interface fixation trends emanating from valgus and varus implant positions that will be of interest to practicing physicians.

Tranexamic acid is a fibrinolytic inhibitor which reduces blood loss in total knee replacement. We examined the effect on blood loss of a standardised intravenous bolus dose of 1 g of tranexamic acid, given at the induction of anaesthesia in patients undergoing total hip replacement and tested the potential prothrombotic effect by undertaking routine venography. In all, 36 patients received 1 g of tranexamic acid, and 37 no tranexamic acid. Blood loss was measured directly per-operatively and indirectly post-operatively. Tranexamic acid reduced the early post-operative blood loss and total blood loss (p = 0.03 and p = 0.008, respectively) but not the intraoperative blood loss. The tranexamic acid group required fewer transfusions (p = 0.03) and had no increased incidence of deep-vein thrombosis. The reduction in early post-operative blood loss was more marked in women (p = 0.05), in whom this effect was dose-related (r = −0.793). Our study showed that the administration of a standardised pre-operative bolus of 1 g of tranexamic acid was cost-effective in reducing the blood loss and transfusion requirements after total hip replacement, especially in women.

The performance of total knee arthroplasty in deeply flexed postures is of increasing concern as the procedure is performed on younger, more physically active and more culturally diverse populations. Several implant design factors, including tibiofemoral conformity, tibial slope and posterior condylar geometry have been shown directly to affect deep flexion performance. The goal of this study was to evaluate the kinematics of a fixed-bearing, asymmetric, medial rotation arthroplasty design in moderate and deep flexion. Thirteen study participants (15 knees) with a medial rotation knee arthroplasty were observed performing a weight-bearing lunge activity to maximum comfortable flexion and kneeling on a padded bench from 90 degrees to maximum comfortable flexion using lateral fluoroscopy. Subjects averaged 74 years of age and nine were female. At maximum weight-bearing flexion, the knees exhibited 115 degrees of implant flexion (102 degrees-125 degrees) and 7 degrees (-3 degrees to 12 degrees) of tibial internal rotation. The medial and lateral condylar translated posteriorly by 2 and 5 mm, respectively. At maximum kneeling flexion, the knees exhibited 119 degrees of implant flexion (101 degrees-139 degrees ) and 5 degrees (-2 degrees to 14 degrees) of tibial internal rotation. The lateral condyle translated posteriorly by 11 mm. The medial rotation knee exhibited motion patterns similar to those observed in the normal knee, but less tibial rotation. The medially conforming articulation beneficially controls femoral AP position in deep flexion, in patients who require such motion as part of their lifestyle.

A sensitive and reproducible measurement of knee surgery outcomes is increasingly needed. However, it has been difficult to compare results because of numerous scoring systems and the publication of data in these systems. Our aim was to compare the more widely used American Knee Society score (AKSS) with the shorter Oxford Knee Score (OKS). The questionnaires were completed preoperatively and at 2, 5, and 10 years postoperatively. A negative correlation of -0.64 (P < .0001) between the OKS and AKSS and the Functional score at 2 years, and a correlation of -0.5 (P < .0001) at 5 and 10 years were found. However, excellent, good, fair, and poor OKS classifications did not correlate well with the AKSS grading (weighted kappa coefficient = 0.06-0.288). This study indicates that the OKS, with its easier analysis and higher compliance rate, can be used more directly to compare studies using the AKSS.

We report the clinical and radiological outcome at ten years of 104 primary total hip replacements (100 patients) using the Metasul metal-on-metal bearing. Of these, 52 had a cemented Stuehmer-Weber polyethylene acetabular component with a Metasul bearing and 52 had an uncemented Allofit acetabular component with a Metasul liner. A total of 15 patients (16 hips) died before their follow-up at ten years and three were lost to follow-up. The study group therefore comprised 82 patients (85 hips). The mean Oxford score at ten years was 20.7 (12 to 42). Six of 85 hips required revision surgery. One was performed because of infection, one for aseptic loosening of the acetabular component and four because of unexplained pain. Histological examination showed an aseptic lymphocytic vasculitis associated lesion-type tissue response in two of these. Continued follow-up is advocated in order to monitor the long-term performance of the Metasul bearing and tissue responses to metal debris.

INTRODUCTION The fast-track assessment clinic (FTAC) is a process to select patients who are very likely to require primary total hip replacement. Selected patients can then be seen in a one-off clinic reducing the number of hospital visits, cost to primary care trusts and delay between referral and treatment. PATIENTS AND METHODS Fifty patients on the waiting list for hip replacement were analysed to see if there were common parameters that led to their inclusion. From these data, fast-track selection criteria (FTSCs) were generated. These FTSCs were used to make a dual comparison of outcomes between 52 patients seen in a traditional clinic. Finally, a pilot study was conducted in which patients fulfilling FTSCs were seen in a designated clinic. RESULTS An Oxford hip score (OHS) of 34 and above combined with severe loss of joint space, severe marginal osteophytes, or both was common to most patients on the waiting list (84%). FTSCs correctly predicted the outcome of the orthopaedic clinic in 38 patients out of a total of 52. During the pilot stage, positive FTSCs were shown to have a positive predictive value of 92% for joint replacement being carried out and a negative predictive value of 46%. CONCLUSIONS An OHS of 34 or above combined with complete loss of joint space and/or severe marginal osteophyte formation can be used to select patients who are very likely to need total hip replacement. These patients can be seen in a clinic that combines assessment of surgical indication with medical fitness for surgery.

Before 2003, all NHS trusts charged locally determined prices for the provision of hip and knee arthroplasty services to their primary care trust (PCT). These charges could be fi xed irrespective of the activity provided (Department of Health (DH), 2002). In 2003–2004, the DH set up a national tariff system so that hospitals would charge PCTs per treatment performed. Similar treatments are grouped together under the same tariff and referred to as a Healthcare Resource Group (HRG).

We audited the relationship between obesity and the age at which hip and knee replacement was undertaken at our centre. The database was analysed for age, the Oxford hip or knee score and the body mass index (BMI) at the time of surgery. In total, 1369 patients were studied, 1025 treated by hip replacement and 344 by knee replacement. The patients were divided into five groups based on their BMI (normal, overweight, moderately obese, severely obese and morbidly obese). The difference in the mean Oxford score at surgery was not statistically significant between the groups (p > 0.05). For those undergoing hip replacement, the mean age of the morbidly obese patients was ten years less than that of those with a normal BMI. For those treated by knee replacement, the difference was 13 years. The age at surgery fell significantly for those with a BMI > 35 kg/m2 for both hip and knee replacement (p > 0.05). This association was stronger for patients treated by knee than by hip replacement.

The effects of the method of fixation and interface conditions on the biomechanics of the femoral component of the Birmingham hip resurfacing arthroplasty were examined using a highly detailed three-dimensional computer model of the hip. Stresses and strains in the proximal femur were compared for the natural femur and for the femur resurfaced with the Birmingham hip resurfacing. A comparison of cemented versus uncemented fixation showed no advantage of either with regard to bone loading. When the Birmingham hip resurfacing femoral component was fixed to bone, proximal femoral stresses and strains were non-physiological. Bone resorption was predicted in the inferomedial and superolateral bone within the Birmingham hip resurfacing shell. Resorption was limited to the superolateral region when the stem was not fixed. The increased bone strain observed adjacent to the distal stem should stimulate an increase in bone density at that location. The remodelling of bone seen during revision of failed Birmingham hip resurfacing implants appears to be consistent with the predictions of our finite element analysis.

We describe the results at five years of a prospective study of a new tri-tapered polished, cannulated, cemented femoral stem implanted in 51 patients (54 hips) with osteoarthritis. The mean age and body mass index of the patients was 74 years and 27.9, respectively. Using the anterolateral approach, half of the stems were implanted by a consultant orthopaedic surgeon and half by six different registrars. There were three withdrawals from the study because of psychiatric illness, a deep infection and a recurrent dislocation. Five deaths occurred prior to five-year follow-up and one patient withdrew from clinical review. In the remaining 51 hips the mean pre-operative Oxford hip score was 47 points which decreased to 19 points at five years (45 hips). Of the stems 49 (98%) were implanted within 1° of neutral in the femoral canal. The mean migration of the stem at five years was 1.9 mm and the survivorship for aseptic loosening was 100%. There was no significant difference in outcome between the consultant and registrar groups. At five years, the results were comparable with those of other polished, tapered, cemented stems. Long-term surveillance continues.

In a prospective 2-year study we have used dual-energy X-ray absorptiometry to measure periprosthetic bone mineral density (BMD) following implantation of a novel, "physiological", acetabular component designed using composite materials.The acetabular components were implanted in hydroxyapatite (HA) and HA-removed options. They were implanted in conjunction with a cemented femoral component in 50 female patients who presented with displaced, subcapital, fractures of the neck of the femur. Regions of interest (ROI) were defined according to De Lee and Charnley. BMD during follow-up was compared with immediate postoperative values for the affected limb.The mean precision error (CV%) was 1.01%, 2.26% and 1.12%, for ROI I, II and III respectively. The mean change in BMD, for both cups, was analyzed. There was no significant difference between the BMD changes induced with the HA- and non-HA-coated cups.After an initial fall in BMD in all 3 ROI at 6 months, ROI I and ROI II showed return to baseline BMD by 2 years. ROI III showed no significant decrease in BMD beyond 6 months, but did not return to baseline levels. Statistical analysis revealed no significant decrease in BMD in ROI I and ROI II at 2 years, compared with immediate postoperative values. The changes in BMD reflect a pattern of maximally reduced stress in the non-weight-bearing zone (ROI III), with preservation of bone density in weight bearing zones ROI I and ROI II. These results support the design principles of the Cambridge cup.

Experimental disruption of the labrum has been shown to compromise its sealing function and alter cartilage lubrication. However, it is not known whether pathological changes to the labrum secondary to femoroacetabular impingement (FAI) have a similar impact on labral function.Does damage to the labrum occurring in association with abnormal femoral morphology affect the labral seal?Using 10 fresh cadaveric specimens (mean age 50 years, ±8), we measured the capacity of the central compartment of the hip (the iliofemoral joint) to maintain a seal during fluid infusion, which may help elucidate the function of the labrum during weightbearing. Specimens with and without abnormal femoral morphology (six normal-appearing specimens and four whose geometry suggested cam-type FAI) were tested in postures observed during functional activities, including simulations of normal gait, stooping, and pivoting. Each specimen with FAI morphology exhibited secondary damage of the labrum and the adjacent chondral surface, whereas specimens of normal morphology were undamaged.Average peak central compartment pressure was reduced during pivoting for specimens with the presence of labral damage secondary to FAI. When placed in pivoting positions, hips with FAI maintained lower fluid pressures within the central compartment compared with intact specimens (15±3 versus 42±8 kPa, respectively; effect size: 1.08 [-0.36 to 2.31]; p=0.007). No differences in peak pressure were observed between groups (FAI versus normal) for postures simulating either gait (21±6 versus 22±4 kPa; p=0.902) or stooping (9±2 versus 8±3 kPa; p=0.775) with the numbers available.The acetabular seal, quantified by the maximum intraarticular pressure, was reduced during pivoting; however, the seal was maintained during simulated gait and stooping.Because degeneration is progressive with repetitive impingement, loss of the labral seal starts to be seen during pivoting and may progress from there, but in this small-sample cadaver study that evaluated specimens in middle adulthood, the seal remains intact during simulated gait and stooping. Our study suggests that labral damage secondary to cam-type FAI may reduce the ability of the labral to provide an adequate seal of the central compartment of the hip during loading; however, the extent to which this is affected requires further investigation.

The function of the infrapatella fat pad (IFP) is debated, but it is thought to have a biomechanical and biological role. Removal of the IFP during total knee arthroplasty (TKA) remains a matter of surgeon preference. This study sought to establish if removal of the IFP during TKA affected patient outcome. Excision of the IFP (not removed, partially excised, or fully excised) and outcome data (Oxford knee Score (OKS) and EQ-5D) were recorded for 1,401 patients (1,417 TKA). There were no differences in the pre-operative scores between the groups. OKS and EQ-5D one-year postoperatively demonstrated significantly (p

Background: An assessment of the effect of surgical repair or reconstruction on the function of the hip labrum is critical to the advancement of hip preservation surgery; however, validated models of the hip that allow the quantification of labral function in functional joint positions have yet to be developed. Purpose: To evaluate (1) whether intra-articular pressures within the hip are regulated by fluid transport between the labrum and femoral head and (2) whether the sealing capacity of the labrum varies with joint posture. Study Design: Descriptive laboratory study. Methods: The sealing ability of the hip labrum was measured during fluid infusion into the central compartments of 8 cadaveric specimens. Additionally, the pathway of fluid transfer from the central to the peripheral compartment was assessed via direct visualization in 3 specimens. The effect of joint posture on the sealing capacity of the labrum was determined by placing all 8 specimens in 10 functional postures. The relationship between pressure resistance and 3-dimensional motion of the femoral head within the acetabulum was quantified using motion analysis and computer modeling. Results: Resistance to fluid transport from the central compartment of the hip was directly controlled by the labrum during loading. Maximum pressure resistance was affected by joint posture ( P = .001). Specifically, positions that increased external rotation of the joint (pivoting) provided an improved seal, while positions that increased flexion combined with internal rotation (stooping) augmented the ease of fluid transport from the central to the peripheral compartment. Maximum pressure resistance was associated with the distance between the labrum and femoral head during pivoting. Conclusion: This study demonstrated that the transfer of fluid from the central compartment of the hip occurs at the junction of the labrum and femoral head. Joint position was shown to strongly affect the sealing function of the labrum and was attributable to the distance between the labrum and femoral head in certain positions. Clinical Relevance: Altering the relationship between the labrum and femoral head may disrupt the sealing ability of the labrum, potentially leaving the joint at risk for pathological changes with time.

The results of patellar fracture fixation using metal wire and non-absorbable polyester (5 Ethibond) are presented. In group 1 (21 cases), the standard "AO" technique using stainless steel wire was used, and in group 2 (16 cases) we used 5 Ethibond. Patients were assigned to the two groups on surgeon preference. Post-operative management in the two groups was similar, with patients being allowed to mobilise as comfort allowed, under the supervision of the physiotherapists. All patients were followed-up until union of the fractures or until further surgical intervention was carried out. At a mean of 2 years and 6 months (range 1-4 years), we reviewed the notes and X-rays of all 37 cases. In group 2 there were no cases of infection but there were three cases of post-operative infections in group 1. Re-operation rate was 6/21 (38%) in group 1 and 1/6 (6%) in group 2. Therefore, the relative risk of re-operation in the metal group is six times that in the non-absorbable polyester group. The risk of infection in the metal group is also higher. These have implication on patient morbidity associated with the operative treatment of patellar fractures. Non-absorbable polyester appears to compare favourably with the use of metallic wire to fix patellar fractures.

Acetabular component extraction following intra-pelvic migration of a total hip replacement can be hazardous to pelvic tissues, vessels and organs. Acetabular component removal is usually performed using an abdominal retroperitoneal approach. We describe a closed reduction of the acetabular component using a traction/manipulation technique. This manoeuvre can be used in cases of intra-pelvic acetabular component migration where the surface contour of the acetabular component is uncomplicated and an interposition membrane separates the implant from adjacent intra-pelvic structures.