Aims

The aim of this study was to estimate the clinical and economic burden of dislocation following primary total hip arthroplasty (THA) in England.

Aims

Routinely collected patient-reported outcome measures (PROMs) have been useful to quantify and quality-assess provision of total hip arthroplasty (THA) and total knee arthroplasty (TKA) in the UK for the past decade. This study aimed to explore whether the outcome following primary THA and TKA had improved over the past seven years.

Aims

To establish the survivorship, function, and metal ion levels in an unselected series of metal-on-metal hip resurfacing arthroplasties (HRAs) performed by a non-designer surgeon.

Aims

The aim of this study was to identify the minimal clinically important difference (MCID), minimal important change (MIC), minimal detectable change (MDC), and patient-acceptable symptom state (PASS) in the Forgotten Joint Score (FJS) according to patient satisfaction six months following total hip arthroplasty (THA) in a UK population.

Aims. This study investigates the use of the metabolic equivalent of task (MET) score in a young hip arthroplasty population, and its ability to capture additional benefit beyond the ceiling effect of conventional patient-reported outcome measures. Methods. From our electronic database of 751 hip arthroplasty procedures, 221 patients were included. Patients were excluded if they had revision surgery, an alternative hip procedure, or incomplete data either preoperatively or at one-year follow-up. Included patients had a mean age of 59.4 years (SD 11.3) and 54.3% were male, incorporating 117 primary total hip and 104 hip resurfacing arthroplasty operations. Oxford Hip Score (OHS), EuroQol five-dimension questionnaire (EQ-5D), and the MET were recorded preoperatively and at one-year follow-up. The distribution was examined reporting the presence of ceiling and floor effects. Validity was assessed correlating the MET with the other scores using Spearman’s rank correlation coefficient and determining responsiveness. A subgroup of 93 patients scoring 48/48 on the OHS were analyzed by age, sex, BMI, and preoperative MET using the other metrics to determine if differences could be established despite scoring identically on the OHS. Results. Postoperatively the OHS and EQ-5D demonstrate considerable negatively skewed distributions with ceiling effects of 41.6% and 53.8%, respectively. The MET was normally distributed postoperatively with no relevant ceiling effect. Weak-to-moderate significant correlations were found between the MET and the other two metrics. In the 48/48 subgroup, no differences were found comparing groups with the EQ-5D, however significantly higher mean MET scores were demonstrated for patients aged < 60 years (12.7 (SD 4.7) vs 10.6 (SD 2.4), p = 0.008), male patients (12.5 (SD 4.5) vs 10.8 (SD 2.8), p = 0.024), and those with preoperative MET scores > 6 (12.6 (SD 4.2) vs 11.0 (SD 3.3), p = 0.040). Conclusion. The MET is normally distributed in patients following hip arthroplasty, recording levels of activity which are undetectable using the OHS. Cite this article: Bone Joint Res 2022;11(5):317–326

Aims. Up to one in five patients undergoing primary total hip (THA) and knee arthroplasty (TKA) require contralateral surgery. This is frequently performed as a staged procedure. This study aimed to determine if outcomes, as determined by the Oxford Hip Score (OHS) and Knee Score (OKS) differed following second-side surgery. Methods. Over a five-year period all patients who underwent staged bilateral primary THA or TKA utilizing the same type of implants were studied. Eligible patients had both preoperative and one year Oxford scores and had their second procedure completed within a mean (2 SDs) of the primary surgery. Patient demographics, radiographs, and OHS and OKS were analyzed. Results. A total of 236 patients met the inclusion criteria, of which 122 were THAs and 114 TKAs. The mean age was 66.5 years (SD 9.4), with a 2:1 female:male ratio. THAs showed similar significant improvements in outcomes following first- and second-side surgery, regardless of sex. In contrast for TKAs, although male patients demonstrated the same pattern as the THAs, female TKAs displayed significantly less improvement in both OKS and its pain component following second-side surgery. Conclusion. Female patients undergoing second-side TKA showed less improvement in Oxford and pain scores compared to the first-side. This difference in outcome following second-side surgery did not apply to male patients undergoing TKA, or to either sex undergoing THA. Cite this article: Bone Jt Open 2021;2(4):243–254

Aims. The aim of this prospective cohort study was to evaluate the early migration of the TriFit cementless proximally coated tapered femoral stem using radiostereometric analysis (RSA). Methods. A total of 21 patients (eight men and 13 women) undergoing primary total hip arthroplasty (THA) for osteoarthritis of the hip were recruited in this study and followed up for two years. Two patients were lost to follow-up. All patients received a TriFit stem and Trinity Cup with a vitamin E-infused highly cross-linked ultra-high molecular weight polyethylene liner. Radiographs for RSA were taken postoperatively and then at three, 12, and 24 months. Oxford Hip Score (OHS), EuroQol five-dimension questionnaire (EQ-5D), and adverse events were reported. Results. At two years, the mean subsidence of the head and tip for the TriFit stem was 0.38 mm (SD 0.32) and 0.52 mm (SD 0.36), respectively. The total migration of the head and tip was 0.55 mm (SD 0.32) and 0.71 mm (SD 0.38), respectively. There were no statistically significant differences between the three to 12 months' migration (p = 0.105) and 12 to 24 months' migration (p = 0.694). The OHS and EQ-5D showed significant improvements at two years. Conclusion. The results of this study suggest that the TriFit femoral stem achieves initial stability and is likely to be stable in the mid and long term. A long-term outcome study is required to assess late mechanisms of failure and the effects of bone mineral density (BMD) related changes. Cite this article: Bone Joint J 2021;103-B(4):644–649

Aims. Cement-in-cement revision of the femoral component represents a widely practised technique for a variety of indications in revision total hip arthroplasty. In this study, we compare the clinical and radiological outcomes of two polished tapered femoral components. Methods. From our prospectively collated database, we identified all patients undergoing cement-in-cement revision from January 2005 to January 2013 who had a minimum of two years' follow-up. All cases were performed by the senior author using either an Exeter short revision stem or the C-Stem AMT high offset No. 1 prosthesis. Patients were followed-up annually with clinical and radiological assessment. Results. A total of 97 patients matched the inclusion criteria (50 Exeter and 47 C-Stem AMT components). There were no significant differences between the patient demographic data in either group. Mean follow-up was 9.7 years. A significant improvement in Oxford Hip Score (OHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and 12-item Short-Form Survey (SF-12) scores was observed in both cohorts. Leg lengths were significantly shorter in the Exeter group, with a mean of -4 mm in this cohort compared with 0 mm in the C-Stem AMT group. One patient in the Exeter group had early evidence of radiological loosening. In total, 16 patients (15%) underwent further revision of the femoral component (seven in the C-Stem AMT group and nine in the Exeter group). No femoral components were revised for aseptic loosening. There were two cases of femoral component fracture in the Exeter group. Conclusion. Our series shows promising mid-term outcomes for the cement-in-cement revision technique using either the Exeter or C-Stem AMT components. These results demonstrate that cement-in-cement revision using a double or triple taper-slip design is a safe and reliable technique when used for the correct indications. Cite this article: Bone Joint J 2021;103-B(7):1215–1221

Aims. To determine the trajectories of patient reported pain and functional disability over five years following total hip arthroplasty (THA) or total knee arthroplasty (TKA). Methods. A prospective, longitudinal cohort sub-study within the National Joint Registry (NJR) was undertaken. In all, 20,089 patients who underwent primary THA and 22,489 who underwent primary TKA between 2009 and 2010 were sent Oxford Hip Score (OHS) and Oxford Knee Score (OKS) questionnaires at six months, and one, three, and five years postoperatively. OHS and OKS were disaggregated into pain and function subscales. A k-means clustering procedure assigned each patient to a longitudinal trajectory group for pain and function. Ordinal regression was used to predict trajectory group membership using baseline OHS and OKS score, age, BMI, index of multiple deprivation, sex, ethnicity, geographical location, and American Society of Anesthesiologists grade. Results. Data described two discrete trajectories for pain and function: ‘level 1’ responders (around 70% of cases) in whom a high level of improvement is sustained over five years, and ‘level 2’ responders who had sustained improvement, but at a lower level. Baseline patient variables were only weak predictors of pain trajectory and modest predictors of function trajectory. Those with worse baseline pain and function tended to show a greater likelihood of following a ‘level 2’ trajectory. Six-month patient-reported outcome measures data reliably predicted the class of five-year outcome trajectory for both pain and function. Conclusion. The available preoperative patient variables were not reliable predictors of postoperative pain and function after THA and TKA. Reviewing patient outcomes at six months postoperatively is a reliable indicator of outcome at five years. Cite this article: Bone Joint J 2021;103-B(6):1111–1118

Aims. We compared the clinical outcomes of curved intertrochanteric varus osteotomy (CVO) with bone impaction grafting (BIG) with CVO alone for the treatment of osteonecrosis of the femoral head (ONFH). Methods. This retrospective comparative study included 81 patients with ONFH; 37 patients (40 hips) underwent CVO with BIG (BIG group) and 44 patients (47 hips) underwent CVO alone (CVO group). Patients in the BIG group were followed-up for a mean of 12.2 years (10.0 to 16.5). Patients in the CVO group were followed-up for a mean of 14.5 years (10.0 to 21.0). Assessment parameters included the Harris Hip Score (HHS), Oxford Hip Score (OHS), Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ), complication rates, and survival rates, with conversion to total hip arthroplasty (THA) and radiological failure as the endpoints. Results. There were no significant differences in preoperative and postoperative HHS or postoperative OHS and JHEQ between the BIG group and the CVO group. Complication rates were comparable between groups. Ten-year survival rates with conversion to THA and radiological failure as the endpoints were not significantly different between groups. Successful CVO (postoperative coverage ratio of more than one-third) exhibited better ten-year survival rates with radiological failure as the endpoint in the BIG group (91.4%) than in the CVO group (77.7%), but this difference was not significant (p = 0.079). Conclusion. Long-term outcomes of CVO with BIG were favourable when proper patient selection and accurate surgery are performed. However, this study did not show improvements in treatment results with the concomitant use of BIG. Cite this article: Bone Joint J 2021;103-B(4):665–671

Aims. The aim of this study was to determine if the Oxford Knee and Hip Score (OKHS) can accurately predict when a primary knee or hip referral is deemed nonsurgical versus surgical by the surgeon during their first consultation, and to identify nonsurgical OKHS screening thresholds. Patients and Methods. We retrospectively reviewed pre-consultation OKHS for all consecutive primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) consultations of a single surgeon over three years. The 1436 knees (1016 patients) and 478 hips (388 patients) included were categorized based on the surgeon’s decision into those offered surgery during the first consultation versus those not (nonsurgical). Spearman’s rank correlation coefficients and receiver operating characteristic (ROC) curve analysis were performed. Results. Oxford Scores were better for the nonsurgical cohorts (p < 0.001) and correlated with the surgical decision (p < 0.001). ROC area under the curve values for knees (0.83, 95% confidence intervals (CI) 0.81 to 0.85) and hips (0.87, 95% CI 0.84 to 0.91) were excellent. A conservative and effective threshold for knees is Oxford Knee Score (OKS) > 32 points (sensitivity = 0.997, negative predictive value (NPV) = 0.992) and for hips is Oxford Hip Score (OHS) > 34 points (sensitivity = 0.997, NPV = 0.978). Severable potential lower OKHS thresholds were identified. Conclusion. Pre-consultation OKHS demonstrate good ability to predict when a primary TKA or THA referral will be deemed nonsurgical in a single surgeon’s practice. Multiple OKHS thresholds can effectively screen out nonsurgical referrals. Cite this article: Bone Joint J 2019;101-B(6 Supple B):23–30

Aims. The purpose of this study was to compare the clinical, radiological, and patient-reported outcome measures (PROMs) in the first 100 consecutive patients undergoing total hip arthroplasty (THA) via a direct superior approach (DSA) with a matched group of patients undergoing THA by the same surgeon, using a posterolateral approach (PLA). Methods. This was a retrospective single surgeon study comparing the first 100 consecutive DSA THA patients with a matched group of patients using a standard PLA. Case notes were examined for patient demographics, length of hospital stay, operating time, intra- and postoperative complications, pain score, satisfaction score, and Oxford Hip Score (OHS). Leg length discrepancy and component positioning were measured from postoperative plain radiographs. Results. The DSA patients had a shorter length of hospital stay (mean 2.09 days (SD 1.20) DSA vs 2.74 days (SD 1.17) PLA; p < 0.001) and shorter time to discharge from the inpatient physiotherapy teams (mean 1.44 days (SD 1.17) DSA vs 1.93 days (SD 0.96) PLA; p < 0.001). There were no differences in operating time (p = 0.505), pain levels up to postoperative day 1 (p = 0.106 to p =0.242), OHS (p = 0.594 to p = 0.815), satisfaction levels (p = 0.066 to p = 0.299), stem alignment (p = 0.240), acetabular component inclination (p < 0.001) and anteversion (p < 0.001), or leg length discrepancy (p = 0.134). Conclusion. While the DSA appears safe and was not associated with a significant difference in PROMs, radiological findings, or intraoperative or postoperative complications, a randomized controlled trial with functional outcomes in the postoperative phase is needed to evaluate this surgical approach formally. Cite this article: Bone Joint J 2021;103-B(3):500–506

Aims. The primary aim of this study was to compare the hip-specific functional outcome of robotic assisted total hip arthroplasty (rTHA) with manual total hip arthroplasty (mTHA) in patients with osteoarthritis (OA). Secondary aims were to compare general health improvement, patient satisfaction, and radiological component position and restoration of leg length between rTHA and mTHA. Methods. A total of 40 patients undergoing rTHA were propensity score matched to 80 patients undergoing mTHA for OA. Patients were matched for age, sex, and preoperative function. The Oxford Hip Score (OHS), Forgotten Joint Score (FJS), and EuroQol five-dimension questionnaire (EQ-5D) were collected pre- and postoperatively (mean 10 months (SD 2.2) in rTHA group and 12 months (SD 0.3) in mTHA group). In addition, patient satisfaction was collected postoperatively. Component accuracy was assessed using Lewinnek and Callanan safe zones, and restoration of leg length were assessed radiologically. Results. There were no significant differences in the preoperative demographics (p ≥ 0.781) or function (p ≥ 0.383) between the groups. The postoperative OHS (difference 2.5, 95% confidence interval (CI) 0.1 to 4.8; p = 0.038) and FJS (difference 21.1, 95% CI 10.7 to 31.5; p < 0.001) were significantly greater in the rTHA group when compared with the mTHA group. However, only the FJS was clinically significantly greater. There was no difference in the postoperative EQ-5D (difference 0.017, 95% CI -0.042 to 0.077; p = 0.562) between the two groups. No patients were dissatisfied in the rTHA group whereas six were dissatisfied in the mTHA group, but this was not significant (p = 0.176). rTHA was associated with an overall greater rate of component positioning in a safe zone (p ≤ 0.003) and restoration of leg length (p < 0.001). Conclusion. Patients undergoing rTHA had a greater hip-specific functional outcome when compared to mTHA, which may be related to improved component positioning and restoration of leg length. However, there was no difference in their postoperative generic health or rate of satisfaction. Cite this article: Bone Joint Res 2021;10(1):22–30

Aims. The classical longitudinal incision used for the direct anterior approach (DAA) to the hip does not follow the tension lines of the skin and can lead to impaired wound healing and poor cosmesis. The purpose of this retrospective study was to determine the satisfaction with the scar, and functional and radiographic outcomes comparing the classic longitudinal incision with a modified skin crease ‘bikini’ when the DAA is used for total hip arthroplasty (THA). Patients and Methods. A total of 964 patients (51% female; 59% longitudinal, 41% ‘bikini’) completed a follow-up questionnaire between two and four years postoperatively, including the Oxford Hip Score (OHS), the University of North Carolina ‘4P’ scar scale (UNC4P) and two items for assessing the aesthetic appearance of the scar and symptoms of numbness. The positioning of the components, rates of heterotopic ossification (HO) and rates of revision were assessed. Results. The mean OHS was similar in both groups (p = 0.41). The mean UNC4P total score was slightly better (p = 0.01) and the proportion of patients who were very satisfied with the cosmetic aspects of the scar was higher in the ‘bikini’ group (p < 0.001). The proportion of patients reporting numbness in the scar was higher in the longitudinal group (14.5% vs 7.5%, respectively, p < 0.001). The abduction angle of the acetabular component, the position of the stem and rates of HO did not differ between the groups. There were no differences in the revision rates of both groups, being 2.3% in the longitudinal and 1.5% in the ‘bikini’ group (p = 0.911). Conclusion. We found that a short oblique ‘bikini’ skin crease incision is safe when used for the DAA at THA, without compromising the positioning of the components or increasing the rate of lateral femoral cutaneous nerve dysaesthesia. Although it leads to a superior scar satisfaction, as it is less extensile, it should be used after having gained experience with the classic longitudinal incision. Cite this article: Bone Joint J 2018;100-B:853–61

Aims. Femoral revision component subsidence has been identified as predicting early failure in revision hip surgery. This comparative cohort study assessed the potential risk factors of subsidence in two commonly used femoral implant designs. Methods. A comparative cohort study was undertaken, analyzing a consecutive series of patients following revision total hip arthroplasties using either a tapered-modular (TM) fluted titanium or a porous-coated cylindrical modular (PCM) titanium femoral component, between April 2006 and May 2018. Clinical and radiological assessment was compared for both treatment cohorts. Risk factors for subsidence were assessed and compared. Results. In total, 65 TM and 35 PCM cases were included. At mean follow-up of seven years (1 to 13), subsidence was noted in both cohorts during the initial three months postoperatively (p < 0.001) then implants stabilized. Subsidence noted in 58.7% (38/65 cases) of the TM cohort (mean 2.3 mm, SD 3.5 mm) compared to 48.8% (17/35) of PCM cohort (mean 1.9 mm, SD 2.6 mm; p = 0.344). Subsidence of PCM cohort were significantly associated with extended trochanteric osteotomy (ETO) (p < 0.041). Although the ETO was used less frequently in PCM stem cohort (7/35), subsidence was noted in 85% (6/7) of them. Significant improvement of the final mean Oxford Hip Score (OHS) was reported in both treatment groups (p < 0.001). Conclusion. Both modular TM and PCM revision femoral components subsided within the femur. TM implants subsided more frequently than PCM components if the femur was intact but with no difference in clinical outcomes. However, if an ETO is performed then a PCM component will subside significantly more and suggests the use of a TM implant may be advisable. Cite this article: Bone Joint J 2020;102-B(6):709–715

Aims. Hip fractures in patients < 60 years old currently account for only 3% to 4% of all hip fractures in England, but this proportion is increasing. Little is known about the longer-term patient-reported outcomes in this potentially more active population. The primary aim is to examine patient-reported outcomes following isolated hip fracture in patients aged < 60 years. The secondary aim is to determine an association between outcomes and different types of fracture pattern and/or treatment implants. Methods. All hip fracture patients aged 18 to 60 years admitted to a single centre over a 15-year period were used to identify the study group. Fracture pattern (undisplaced intracapsular, displaced intracapsular, and extracapsular) and type of operation (multiple cannulated hip screws, angular stable fixation, hemiarthroplasty, and total hip replacement) were recorded. The primary outcome measures were the Oxford Hip Score (OHS), the EuroQol five-dimension questionnaire (EQ-5D-3L), and EQ-visual analogue scale (VAS) scores. Preinjury scores were recorded by patient recall and postinjury scores were collected at a mean of 57 months (9 to 118) postinjury. Ethics approval was obtained prior to study commencement. Results. A total of 72 patients were included. There was a significant difference in pre- and post-injury OHS (mean 9.8 point reduction (38 to -20; p < 0.001)), EQ-5D (mean 0.208 reduction in index (0.897 to -0.630; p < 0.001)), and VAS , and VAS (mean 11.6 point reduction (70 to -55; p < 0.001)) Fracture pattern had a significant influence on OHS (p < 0.001) with extracapsular fractures showing the least favourable long-term outcome. Fixation type also impacted significantly on OHS (p = 0.011) with the worst outcomes in patients treated by hemiarthroplasty or angular stable fixation. Conclusion. There is a significant reduction in function and quality of life following injury, with all three patient-reported outcome measures used, indicating that this is a substantial injury in younger patients. Treatment with hemiarthroplasty or angular stable devices in this cohort were associated with a less favourable hip score outcome. Cite this article: Bone Joint J 2020;102-B(6):766–771

Objectives. The Oxford hip score (OHS) is a 12-item questionnaire designed and developed to assess function and pain from the perspective of patients who are undergoing total hip replacement (THR). The OHS has been shown to be consistent, reliable, valid and sensitive to clinical change following THR. It has been translated into different languages, but no adequately translated, adapted and validated Danish language version exists. Methods. The OHS was translated and cross-culturally adapted into Danish from the original English version, using methods based on best-practice guidelines. The translation was tested for psychometric quality in patients drawn from a cohort from the Danish Hip Arthroplasty Register (DHR). Results. The Danish OHS had a response rate of 87.4%, no floor effect and a 19.9% ceiling effect (as expected in post-operative patients). Only 1.2% of patients had too many items missing to calculate a sum score. Construct validity was adequate and 80% of our predefined hypotheses regarding the correlation between scores on the Danish OHS and the other questionnaires were confirmed. The intraclass correlation (ICC) of the different items ranged from 0.80 to 0.95 and the average limits of agreement (LOA) ranged from -0.05 to 0.06. The Danish OHS had a high internal consistency with a Cronbach’s alpha of 0.99 and an average inter-item correlation of 0.88. Conclusions. This Danish version of the OHS is a valid and reliable patient-reported outcome measurement instrument (PROM) with similar qualities to the original English language version.

Objectives. Modern metal-on-metal (MoM) hip resurfacing arthroplasty (HRA), while achieving good results with well-orientated, well-designed components in ideal patients, is contraindicated in women, men with head size under 50 mm, or metal hypersensitivity. These patients currently have no access to the benefits of HRA. Highly crosslinked polyethylene (XLPE) has demonstrated clinical success in total hip arthroplasty (THA) and, when used in HRA, potentially reduces metal ion-related sequelae. We report the early performance of HRA using a direct-to-bone cementless mono-bloc XLPE component coupled with a cobalt-chrome femoral head, in the patient group for whom HRA is currently contraindicated. Methods. This is a cross-sectional, observational assessment of 88 consecutive metal-on-XLPE HRAs performed in 84 patients between 2015 and 2018 in three centres (three surgeons, including the designer surgeon). Mean follow-up is 1.6 years (0.7 to 3.9). Mean age at operation was 56 years (. sd. 11; 21 to 82), and 73% of implantations were in female patients. All patients were individually counselled, and a detailed informed consent was obtained prior to operation. Primary resurfacing was carried out in 85 hips, and three cases involved revision of previous MoM HRA. Clinical, radiological, and Oxford Hip Score (OHS) assessments were studied, along with implant survival. Results. There was no loss to follow-up and no actual or impending revision or reoperation. Median OHS increased from 24 (interquartile range (IQR) 20 to 28) preoperatively to 48 (IQR 46 to 48) at the latest follow-up (48 being the best possible score). Radiographs showed one patient had a head-neck junction lucency. No other radiolucency, osteolysis, component migration, or femoral neck thinning was noted. Conclusion. The results in this small consecutive cohort suggest that metal-on-monobloc-XLPE HRA is successful in the short term and merits further investigation as a conservative alternative to the current accepted standard of stemmed THA. However, we would stress that survival data with longer-term follow-up are needed prior to widespread adoption. Cite this article: R. B. C. Treacy, J. P. Holland, J. Daniel, H. Ziaee, D. J. W. McMinn. Preliminary report of clinical experience with metal-on-highly-crosslinked-polyethylene hip resurfacing. Bone Joint Res 2019;8:443–450. DOI: 10.1302/2046-3758.810.BJR-2019-0060.R1

Objective. The objective of this study was to explore dimensionality of the Oxford Hip Score (OHS) and examine whether self-reported pain and functioning can be distinguished in the form of subscales. Methods. This was a secondary data analysis of the UK NHS hospital episode statistics/patient-reported outcome measures dataset containing pre-operative OHS scores on 97 487 patients who were undergoing hip replacement surgery. . Results. The proposed number of factors to extract depended on the method of extraction employed. Velicer’s Minimum Average Partial test and the Parallel Analysis suggested one factor, the Cattell’s scree test and Kaiser-over-1 rule suggested two factors. Exploratory factor analysis demonstrated that the two-factor OHS had most of the items saliently loading either of the two factors. These factors were named ‘Pain’ and ‘Function’ and their respective subscales were created. There was some cross-loading of items: 8 (pain on standing up from a chair) and 11 (pain during work). These items were assigned to the ‘Pain’ subscale. The final ‘Pain’ subscale consisted of items 1, 8, 9, 10, 11 and 12. The ‘Function’ subscale consisted of items 2, 3, 4, 5, 6 and 7, with the recommended scoring of the subscales being from 0 (worst) to 100 (best). Cronbach’s alpha was 0.855 for the ‘Pain’ subscale and 0.861 for the ‘Function’ subscale. A confirmatory factor analysis demonstrated that the two-factor model of the OHS had a better fit. However, none of the one-factor or two-factor models was rejected. Conclusion. Factor analyses demonstrated that, in addition to current usage as a single summary scale, separate information on pain and self-reported function can be extracted from the OHS in a meaningful way in the form of subscales. Cite this article: Bone Joint Res 2014;3:305–9