Identification of patients at risk of not achieving minimally clinically important differences (MCID) in patient reported outcome measures (PROMs) is important to ensure principled and informed pre-operative decision making. Machine learning techniques may enable the generation of a predictive model for attainment of MCID in hip arthroscopy. Aims: 1) to determine whether machine learning techniques could predict which patients will achieve MCID in the iHOT-12 PROM 6 months after arthroscopic management of femoroacetabular impingement (FAI), 2) to determine which factors contribute to their predictive power. Data from the UK Non-Arthroplasty Hip Registry database was utilised. We identified 1917 patients who had undergone hip arthroscopy for FAI with both baseline and 6 month follow up iHOT-12 and baseline EQ-5D scores. We trained three established machine learning algorithms on our dataset to predict an outcome of iHOT-12 MCID improvement at 6 months given baseline characteristics including demographic factors, disease characteristics and PROMs. Performance was assessed using area under the receiver operating characteristic (AUROC) statistics with 5-fold cross validation. The three machine learning algorithms showed quite different performance. The linear logistic regression model achieved AUROC = 0.59, the deep neural network achieved AUROC = 0.82, while a random forest model had the best predictive performance with AUROC 0.87. Of demographic factors, we found that BMI and age were key predictors for this model. We also found that removing all features except baseline responses to the iHOT-12 questionnaire had little effect on performance for the random forest model (AUROC = 0.85). Disease characteristics had little effect on model performance. Machine learning models are able to predict with good accuracy 6-month post-operative MCID attainment in patients undergoing arthroscopic management for FAI. Baseline scores from the iHOT-12 questionnaire are sufficient to predict with good accuracy whether a patient is likely to reach MCID in post-operative PROMs

Aims

The Forgotten Joint Score-12 (FJS-12) is a validated patient-reported outcome measure (PROM) tool designed to assess artificial prosthesis awareness during daily activities following total hip arthroplasty (THA). The patient-acceptable symptom state (PASS) is the minimum cut-off value that corresponds to a patient’s satisfactory state-of-health. Despite the validity and reliability of the FJS-12 having been previously demonstrated, the PASS has yet to be clearly defined. This study aims to define the PASS of the FJS-12 following primary THA.

MCID and PASS are thresholds driven from PROMS to reflect clinical effectiveness. Statistical significance can be derived from a change in PROMS, whereas MCID and PASS reflect clinical significance. Its role has been increasingly used in the world of young adult hip surgery with several publications determining the thresholds for Femoro-acetabular impingement FAI. To our knowledge MCID and PASS for patient undergoing PAO for dysplasia has not been reported. 593 PAOs between 1/2013 and 7/2023 were extracted from the Northumbria Hip Preservation Registry. Patients with available PROMS at 1year and/or 2years were included. PAOs for retroversion, residual Perthes and those combined with FO were excluded. MCID was calculated using the distribution method 0.5SD of baseline score(1). PASS was calculated using anchor method, ROC analysis performed, and value picked maximizing Youden index. A Logistic Regression analysis was performed to determine which independent variables correlated with achieving MCID and PASS. The MCID threshold for iHOt12 was 8.6 with 83.4 and 86.3 % of patients achieved it at 1 and 2 years respectively. The PASS score at 1 and 2 year follow up was 43 and 44 respectively, with 72.6 and 75.2% achieving it at 1 and 2 year postop. At 2 years a Higher preop iHOT 12 was associated with not achieving MCID and PASS (p<0.05). Preop acetabular version was negatively correlated with achieving MCID and previous hip arthroscopy was negatively correlated with PASS. The % of patients achieving MCID and PASS mimics that of FAI surgery (2). The negative correlation with preop iHOT12 reaffirms the importance of patient selection. The negative correlation of hip arthroscopy highlights the importance of having a high index of suspicion for dysplasia prior to hip arthroscopy and poorer outcomes of patients with mixed CAM and dysplasia pathology

Femoroacetabular Impingement (FAI) syndrome, characterised by abnormal hip contact causing symptoms and osteoarthritis, is measured using the International Hip Outcome Tool (iHOT). This study uses machine learning to predict patient outcomes post-treatment for FAI, focusing on achieving a minimally clinically important difference (MCID) at 52 weeks. A retrospective analysis of 6133 patients from the NAHR who underwent hip arthroscopic treatment for FAI between November 2013 and March 2022 was conducted. MCID was defined as half a standard deviation (13.61) from the mean change in iHOT score at 12 months. SKLearn Maximum Absolute Scaler and Logistic Regression were applied to predict achieving MCID, using baseline and 6-month follow-up data. The model's performance was evaluated by accuracy, area under the curve, and recall, using pre-operative and up to 6-month postoperative variables. A total of 23.1% (1422) of patients completed both baseline and 1-year follow-up iHOT surveys. The best results were obtained using both pre and postoperative variables. The machine learning model achieved 88.1% balanced accuracy, 89.6% recall, and 92.3% AUC. Sensitivity was 83.7% and specificity 93.5%. Key variables determining outcomes included MCID achievement at 6 months, baseline iHOT score, 6-month iHOT scores for pain, and difficulty in walking or using stairs. The study confirmed the utility of machine learning in predicting long-term outcomes following arthroscopic treatment for FAI. MCID, based on the iHOT 12 tools, indicates meaningful clinical changes. Machine learning demonstrated high accuracy and recall in distinguishing between patients achieving MCID and those who did not. This approach could help early identification of patients at risk of not meeting the MCID threshold one year after treatment

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. Methods. During a one-year period, 461 patients underwent a primary THA and completed preoperative and six-month FJS, with a mean age of 67.2 years (22 to 93). At six months, patient satisfaction was recorded as very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied. The difference between patients recording neutral (n = 31) and satisfied (n = 101) was used to define the MCID. MIC for a cohort was defined as the change in the FJS for those patients declaring their outcome as satisfied, whereas receiver operating characteristic curve analysis was used to determine the MIC for an individual and the PASS. Distribution-based methodology was used to calculate the MDC. Results. Using satisfaction as the anchor, the MCID for the FJS was 8.1 (95% confidence interval (CI) 3.7 to 15.9; p = 0.040), which was affirmed when adjusting for confounding. The MIC for the FJS for a cohort of patients was 17.7 (95% CI 13.7 to 21.7) and for an individual patient was 18. The MDC90 for the FJS was eight, meaning that 90% of patients scoring more than this will have experienced a real change that is beyond measurement error. The PASS threshold for the FJS was defined as 29. Conclusion. The MCID and MIC can be used respectively to assess whether there is a clinical difference between two groups, or whether a cohort or patient has had a meaningful change in their FJS. Both values were greater than measurement error (MDC90), suggesting a real change. The PASS threshold for the postoperative FJS can be used as a marker of achieving patient satisfaction following THA. Cite this article: Bone Joint J 2021;103-B(12):1759–1765

To evaluate the impact of routine capsular repair on patient-reported outcomes, survivorship and achievability of clinically important improvement, minimum 5-years post-surgery. Our prospective institutional registry was reviewed for cases undergoing primary HA for FAI, and stratified into two groups depending on whether the capsule was repaired or not. Routine repair was introduced in late 2013. The No Repair group consisted of patients undergoing HA between Jan 2010-June 2013 while the Repair group consisted of patients undergoing HA between Jan 2015-Sept 2018. Exclusion criteria consisted of >50 years, Tonnis>1, dysplasia(LCEA<25), concomitant hip pathologies. PROMs consisted of mHHS, SF36 and UCLA. Metrics of clinically important improvement was evaluated using MCID and SCB. Rates of repeat HA or THA conversion were recorded. 985 cases were included (359 No Repair; 626 Repair), 86% male, average age 27.4±6.7years. Significant improvement in all PROMs at minimum 5-years was observed for both groups (p<0.001 for all; large effect sizes for mHHS and SF36, medium effect sizes for UCLA). At 5-years post-op there was no significant difference between groups for mHHS(p=0.078) or UCLA(0.794). SF36 was significantly poorer for those cases undergoing routine repair(p<0.001) however effect size was small (0.20). Thresholds of MCID and SCB were calculated as 69% and 86% for mHHS, 64% and 77% for UCLA, 43% and 60% for SF36. Both groups achieved MCID and SCB at similar rates for mHHS and UCLA. A significantly lower proportion of cases in the repair groups achieved MCID for SF36 (53.6% vs 63.5%, p=0.034) and SCB for SF36 (37.3% vs 52.8%, p<0.001). No significant difference between groups for THA conversion (0.6% No Repair vs 0.5% Repair) or repeat HA (9.7% No Repair vs 8.1% Repair). Routinely repairing the capsule following HA for FAI demonstrates no clinical benefit over not repairing the capsule 5 years post-surgery

Young patients undergoing THA or hip used. HOS and iHOT33 have demonstrated to be useful in hip preservation surgery but never used in THA. The aim of the study was to evaluate long-term clinical outcomes with HOS and iHOT33 in hip arthroscopy and THA. We conducted a retrospective study with prospective data collection of 118 consecutive young patients (<65 y.o.) between 2008 to 2012 who underwent hip arthroscopy or THA. The mean follow-up was 12.05 years. All surgeries were done by the same senior surgeon. PROMs used were iHOT-33 and HOS preoperatively, at one year and 10 years. SPSS Statistics Grad Pack 28.0 software was used for statistical analysis. Arthroscopy Group (57 patients): Mean age 35.36 years. 55.93% were male. iHOT33 mean differential improvement was 24.43 at 1 year, 70,17% exceed MCID and 49,1% SCB. HOS mean differential improvement was 16.26 at one year. 54,38 % patients exceed MCID and 49,36% SCB. At 10 years, iHOT33 mean differential improvement was 14,36 and 12.56 for HOS. Regarding complications, 3 patients underwent THA (5.26%) and 10 (17.54%) continued with groin pain. THA Group (61 patients): Mean age 52,54 years. 55.73% were male. Cementless THA was used in all patients with ceramic on ceramic used in 77%. iHOT33 mean differential improvement was 41,57 at 1 year. 95,08% patients exceed MCID and 85,25% SCB. HOS mean differential improvement was 16.57 points at one year. 85,25% patients exceed MCID and 81,97% SCB. At 10 years, iHOT33 mean differential improvement was 20,15 and 14.12 for HOS. Regarding complications, 1 patient underwent DAIR for infection (1.64%) and 1 dislocation with close reduction (1.64%). iHOT33 or HOS scores should be considered to be used in young active patients after hip preserving surgery or THA, with more predictable results at long-term in THA group

The results of total hip arthroplasty (THA) revisions to correct leg length discrepancy (LLD) are not clear, with only two former limited series (< 25 patients). Therefore, we conducted a retrospective study of THA revisions for LLD to determine: 1) the change in LLD, 2) the function outcomes and whether obtaining equal leg lengths influenced function, 3) the complication and survival rates. This multicenter study included 57 patients: 42 THA revisions for limb shortening and 15 revisions for limb lengthening. LLD was measured on conventional radiographs and EOS. The Oxford-12 and FJS outcome scores were collected and the number of patients achieving the Oxford-12 MCID. The revisions were carried out a mean of 2.8 years after the index THA. The median LLD decreased from 7.5 mm (IQR: [5;12]) to 1 mm (IQR: [0.5;2.5]) at follow-up (p=0.0002). Overall, 55 of 57 patients (96%) had < 5 mm LLD at follow-up and 12 patients (21%) had equal leg lengths. The complication rate was 25%: 12 mechanical complications (8 periprosthetic femoral fractures, 2 stem loosening and 1 cup loosening, 1 dislocation) and 1 periprosthetic infection. The patient satisfaction was high with a median FJS of 79.2/100 and 77% of patients reached the Oxford-12 MCID. Lengthening procedures had significantly worst function than shortening (38% vs 91% of patients achieving the Oxford-12 MCID (p=0.0004)). Survivorship was 85% (95% CI: 77.9 – 92.5) at 2 years and 77% (95% CI: 66.3 – 87.1) at 4.6 years when using re-revision for any reason as the endpoint. When LLD after THA does not respond to conservative management, revision THA should be considered. Although revision THA for LLD improved medium-term functional outcomes with a high patient satisfaction rate, especially for shortening procedures, the complication rate was high, particularly related to periprosthetic femoral fracture

There is a limited literature available describing the various diagnostic modalities and treatment options for the management of subspine impingement (SSI). We developed a study to evaluate the clinical improvement at 1 year and 5 years, with iHOT 33 and HOS hip scores. (1) Do patients with subspine compression improve with arthroscopic treatment clinically at short term follow-up (1 year)? (2) Is the improvement maintained in the mid-term (5 years)?. 43 young patients with subspine compression (prominent anterior inferior iliac spine) treated arthroscopically between January 2010 and December 2021 were included. Patients completed the iHOT33, HOS-SPORT and HOS-ADL questionnaires before surgery, 1 year and 5 years follow up. We evaluated pre and postoperative differences at one year and at 5 years. Minimum Clinically Significant Difference (MCID) and the Substantial Clinical Benefit (SCB) were used to stablish clinical improvement. Mean age was 37.38 years and 66% were males. Almost 75% and 70% of our patients exceed the MCID and the SCB respectively in all the questionnaires after 1 year-follow up. However, at 5 years-follow up, nearly 70% and 65% of the patients exceeded MCID and SCB respectively. We demonstrate that arthroscopic treatment of subspine impingement as an effective treatment for Subspine impingement. However, it is necessary larger sample size and longer follow up period to analyze the long-term results to demonstrate this treatment as the “gold standard”

Introduction. Meaningful clinical improvement as demonstrated through patient-reported outcome measures (PROMs) are increasingly used to evaluate success of total hip arthroplasty (THA) procedures. This patient perspective can provide a full picture when used with clinical data to best evaluate surgical outcomes. Methods. All primary THA procedures reported to the American Joint Replacement Registry from 2012–2018 with linked pre-operative and 1-year post-operative functional or anatomical PROMs were included. The achievement of minimal clinically-important difference (MCID) was calculated using the distribution method. Logistic regression models with covariate adjustment for patient demographics, American Society of Anesthesiologists (ASA) score, and body mass index (BMI) were constructed to identify associations with PROMs. Results were analyzed based on hospital size (small, medium and large) and teaching type (non-teaching, minor and major) based on the American Hospital Association Survey (2015). Results. There were 3,952 THA with pre-operative and 1-year post-operative PROMs. The five types of PROMs collected include: HOOS (n=731), HOOS Jr. (n=295), PROMIS-10 (n=1,074), SF-36 (n=976), VR-12 (1,262). The average age was 66.3±10.5 years, and the majority were female (54.7%). 53.1% of THA patients achieved MCID. Age and gender were statistically significant, while ASA score and BMI classification were not. As age increased by 1 year, the odds of achieving MCID increased 0.8% (OR 0.992, 95%CI 0.984, 0.999) and a minor versus major teaching hospital was 20.8% less likely to achieve MCID (p<0.04). While small hospital sizes had significantly fewer linked PROMs (6.5% of all linked PROMs), only 44.5% achieved MCID compared to medium (52.3%) and large (54.5%) hospitals (p<0.02). Conclusion. Older patient age, major teaching hospitals, and large hospitals achieved higher levels of MCID after THA. Identifying patients that are less likely to achieve MCID can aid physicians by determining patients at risk for poor outcomes, then guiding patient expectations and providing patient-centered care. For any tables or figures, please contact the authors directly

Aims. It is not known whether preservation of the capsule of the hip positively affects patient-reported outcome measures (PROMs) in total hip arthroplasty using the direct anterior approach (DAA-THA). A recent randomized controlled trial found no clinically significant difference at one year postoperatively. This study aimed to determine whether preservation of the anterolateral capsule and anatomical closure improve the outcome and revision rate, when compared with resection of the anterolateral capsule, at two years postoperatively. Methods. Two consecutive groups of patients whose operations were performed by the senior author were compared. The anterolateral capsule was resected in the first group of 430 patients between January 2012 and December 2014, and preserved and anatomically closed in the second group of 450 patients between July 2015 and December 2017. There were no other technical changes between the two groups. Patient characteristics, the Charlson Comorbidity Index (CCI), and surgical data were collected from our database. PROM questionnaires, consisting of the Oxford Hip Score (OHS) and Core Outcome Measures Index (COMI-Hip), were collected two years postoperatively. Data were analyzed with generalized multiple regression analysis. Results. The characteristics, CCI, operating time, and length of stay were similar in both groups. There was significantly less blood loss in the capsular preservation group (p = 0.037). The revision rate (n = 3, (0.6%) in the resected group, and 1 (0.2%) in the preserved group) did not differ significantly (p = 0.295). Once adjusted for demographic and surgical factors, the preserved group had significantly worse PROMs: + 0.24 COMI-Hip (p < 0.001) and -1.6 OHS points (p = 0.017). However, the effect sizes were much smaller than the minimal clinically important differences (MCIDs) of 0.95 and 5, respectively). The date of surgery (influencing, for instance, the surgeon’s age) was not a significant factor. Conclusion. Based on the MCID, the lower PROMs in the capsular preservation group do not seem to have clinical relevance. They do not, however, confirm the expected benefit of capsular preservation reported for the posterolateral approach. Cite this article: Bone Joint J 2022;104-B(7):826–832

Introduction. Patients with hip abductor tendon tears amenable to endoscopic repair tend to be severely disabled and older. However, low preop baseline patient reported outcome (PRO) and advancing age are each often reported to be a harbinger of poor result with hip arthroscopy. Thus, the purpose of this study is to report the demographic makeup of this population and how these patients faired in terms of preop scores and reaching both Minimal Clinically Important Difference (MCID) and Substantial Clinical Benefit (SCB). Methods. Sixty-six consecutive hips in 64 patients (2 bilateral) undergoing endoscopic abductor tendon repair with a hollow core bioabsorbable suture anchor and having achieved two-year follow-up were prospectively assessed with modified Harris Hip Score (mHHS) and international Hip Outcome Tool (iHOT) scores. The MCID for patients undergoing hip arthroscopy has previously been determined as 8 for the mHHS and 13 for the iHOT. SCB has been determined as 20 for the mHHS and 28 for the iHOT. Subgroups were compared using the independent samples t-test. Results. The average age was 57 years (range 22–83 years) with 59 females and 5 males. Post-operative follow-up averaged 28 months (range 24–60). There were 33 full-thickness and 33 partial-thickness tears; 39 gluteus medius tears, 25 medius and minimus tears, and 2 isolated minimus tears. Among the 66 hips, the average preop mHHS was 48.8 with 98.5% achieving MCID and 93.8% SCB. Among 60 hips that had complete iHOT data, the average preop score was 30.0 with 98.3% achieving MCID and 88.3% SCB. There were no complications. One patient underwent repeat arthroscopy for joint debridement at 12 months following abductor repair, and one subsequently underwent total hip replacement at 11 months following repair. There was no statistically significant difference between subgroups of full thickness/partial thickness tears, or single/two tendon tears. Conclusion. This report of endoscopic abductor tendon repair represents a heterogeneous group of single and two tendon involvement with partial and full thickness tears. Collectively these patients can respond exceptionally well in terms of MCID (98.5% mHHS; 98.3% iHOT) and SCB (93.8% mHHS; 88.3% iHOT), even in the presence of low preop baseline scores (average 48.8 mHHS; 30 iHOT) and older age (average 57 years). For any tables or figures, please contact the authors directly

Current treatment options for displaced acetabular fractures in elderly patients include non-surgical management, surgical fixation and surgical fixation with simultaneous hip replacement, the so-called “fix-and-replace”™. There remains a paucity of evidence to guide surgeons in decision making for these difficult injuries. The aim of this study was to assess the feasibility of performing an appropriately powered RCT between treatment options for acetabular fractures in older patients. This was an NIHR funded feasibility triple-arm RCT with participation from 7 NHS MTCs. Patients older than 60 were recruited if they had an acetabular fracture deemed sufficiently displaced for the treating surgeon to consider surgical fixation. Randomisation was performed on a 1:1:1 basis. The three treatment arms were non-surgical management, surgical fixation and fix-and-replace. Feasibility was assessed by willingness of patients to participate and clinicians to recruit, drop out rate, estimates of standard deviation to inform the sample size calculation for the full trial and completion rates to inform design of a future definitive trial. EQ-5D was the primary outcome measure at 6 months, OHS and Disability Rating Index were secondary outcome measures. Of 117 eligible patients, 60 were randomised whilst 50 declined study participation. Nine patients did not receive their allocated intervention. Analysis was performed on an intention to treat basis. During the study period 4 patients withdrew before final review, 4 patients died and 1 was lost to follow-up. The estimated sample size for a full scale study was calculated to be 1474 participants for an EQ-5D MCID of 0.06 with a power of 0.8. This feasibility study suggests a full scale trial would require international collaboration. This study also has provided observed safety data regarding mortality and morbidity for the fix-and-replace procedure to aid surgeons in the decision-making process when considering treatment options

To investigate whether anterior pelvic plane-pelvic tilt (APP-PT) is associated with distinct hip pathomorphologies, we asked: (1) Is there a difference in APP-PT between symptomatic young patients eligible for joint preservation surgery and an asymptomatic control group? (2) Does APP-PT vary between distinct acetabular and femoral pathomorphologies? (3) Does APP-PT differ in symptomatic hips based on demographic factors?. IRB-approved, single-center, retrospective, case-control, comparative study in 388 symptomatic hips (357) patients (mean age 26 ± 2 years [range 23 to 29], 50% females) that presented to our tertiary center for joint preservation over a five year-period. Patients were allocated to 12 different morphologic subgroups. The overall study group was compared to a control group of 20 asymptomatic hips (20 patients). APP-PT was assessed in all patients based on AP pelvis X-rays using the validated HipRecon software. Values between overall and control group were compared using an independent samples t-test. Multiple regression analysis was performed to examine the influences of diagnoses and demographic factors on APP-PT. Minimal clinically important difference (MCID) of APP-PT was defined as >1 standard deviation. No significant differences in APP-PT between the control group and overall group (1.1 ± 3.0° [−4.9 to 5.9] vs 1.8 ± 3.4° [−6.9 to 13.2], p = 0.323) were observed. Acetabular retroversion and overcoverage groups showed higher APP-PT compared to the control group (both p < 0.05) and were the only diagnoses with significant influence on APP-PT in the stepwise multiple regression analysis. However, all observed differences were below the MCID. Demographic factors age, gender, height, weight and BMI showed no influence on APP-PT. APP-PT across different hip pathomorphologies showed no clinically significant variation. It does not appear to be a relevant contributing factor in the evaluation of young patients eligible for hip preservation surgery

Aims. Responsiveness and ceiling effects are key properties of an outcome score. No such data have been reported for the original English version of the International Hip Outcome Tool 12 (iHOT-12) at a follow-up of more than four months. The aim of this study was to identify the responsiveness and ceiling effects of the English version iHOT-12 in a series of patients undergoing hip arthroscopy for intra-articular hip pathology at a minimum of one year postoperatively. Methods. A total of 171 consecutive patients undergoing hip arthroscopy with a diagnosis of femoroacetabular impingement (FAI) under the care of a single surgeon between January 2013 and March 2017 were included. iHOT-12 and EuroQol 5D-5L (EQ-5D-5L) scores were available pre- and postoperatively. Effect size and ceiling effects for the iHOT-12 were calculated with subgroup analysis. Results. A total of 122 patients (71.3%) completed postoperative PROMs scores with median follow-up of 24.3 months (interquartile range (IQR) 17.2 to 33.5). The median total cohort iHOT-12 score improved significantly from 31.0 (IQR 20 to 58) preoperatively to 72.5 (IQR 47 to 90) postoperatively (p < 0.001). The effect size (Cohen’s d) was 1.59. In all, 33 patients (27%) scored within ten points (10%) of the maximum score and 38 patients (31.1%) scored within the previously reported minimal clinically important difference (MCID) of the maximum score. Furthermore, nine (47%) male patients aged < 30 years scored within 10% of the maximum score and ten (53%) scored within the previously reported MCID of the maximum score. Conclusion. There is a previously unreported ceiling effect of the iHOT-12 at a minimum one-year follow-up which is particularly marked in young, male patients following hip arthroscopy for FAI. This tool may not have the maximum measurement required to capture the true outcome following this procedure. Cite this article: Bone Joint J 2020;102-B(8):1010–1015

This study aims to describe the characteristics and outcomes of patients who reported their pre-operative quality of life (QoL) was ‘worse than death’ (‘WTD’) prior to hip arthroscopy (HA) or peri-acetabular osteotomy (PAO). Adult patients who underwent HA or PAO between 1. st. January 2012 and 31. st. October 2020 were extracted from the UK Non-Arthroplasty Hip Registry. International Hip Outcome Tool 12 (iHOT-12) and EuroQol-5 Dimensions (EQ-5D) index questionnaires were collected pre-operatively and at 6 and 12 months. WTD was defined as an EQ-5D score of less than zero. Chi-squared and t-tests were used to compare categorical and continuous variables respectively. 8493 procedures (6355 HA, 746 PAO) were identified in whom 7101 (84%) returned pre-operative EQ-5D questionnaires. 283 HA and 52 PAOs declared their pre-operative QoL to be ‘WTD’. Compared to those patients with pre-operative QoL ‘better than death’ (n=6072, control group) (EQ-5D ≥ zero) patients reporting ‘WTD’ function prior to HA were more likely to be female (66% vs 59%, p = 0.013), of higher body mass index (mean 27.6 kg/m. 2. (SD 5.9) vs 25.7 kg/m. 2. (4.5), p < 0.0001) however there were no statistically significant differences in mean age (36.8 vs 36.4 years), femoroacetabular impingement pattern, or femoral or acetabular cartilage lesion severity. There were no significant demographic differences for PAO. For HA, iHOT-12 scores in WTD patients were significantly poorer pre- [10.8 (95% CI 9.6 to 12.0) vs 33.3 (32.8 to 33.8)] and 12 months post-operatively [34.9 (29.0 to 40.8) vs 59.3 (58.2 to 60.4)] compared to controls. Whilst the majority of patients saw improvement in their scores (p <0.0001), a significantly smaller proportion achieved the minimum clinically important difference for iHOT-12 by 12 months. (51% in the WTD group vs 65% in the control group). Similar trends were observed for PAO. Patients with WTD quality of life may benefit less from hip preservation surgery and should be counselled accordingly regarding expectations. Although the scores improve, only 51% achieve scores beyond MCID

Aims. It is not known whether change in patient-reported outcome measures (PROMs) over time can be predicted by factors present at surgery, or early follow-up. The aim of this study was to identify factors associated with changes in PROM status between two-year evaluation and medium-term follow-up. Patients and Methods. Patients undergoing Birmingham Hip Resurfacing completed the Veteran’s Rand 36 (VR-36), modified Harris Hip Score (mHHS), Tegner Activity Score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at two years and a minimum of three years. A change in score was assessed against minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) thresholds. Binary logistic regression was used to assess the relationship between patient factors and deterioration in PASS status between follow-ups. Results. Overall, 18% of patients reported reductions in mHHS total score exceeding MCID, and 21% reported similar reductions for WOMAC function scores. Nonetheless, almost all patients remained above PASS thresholds for WOMAC function (98%) and mHHS (93%). Overall, 66% of patients with mHHS scores < PASS at two years reported scores > PASS at latest follow-up. Conversely, 6% of patients deteriorated from > PASS to < PASS between follow-ups. Multivariable modelling indicated body mass index (BMI) > 27 kg/m. 2. , VR-36 Physical Component Score (PCS) < 51, VR-36 Mental Component Score (MCS) > 55, mHHS < 84 at two years, female sex, and bone graft use predicted these deteriorating patients with 79% accuracy and an area under the curve (AUC) of 0.84. Conclusion. Due to largely acceptable results at a later follow-up, extensive monitoring of multiple PROMs is not recommended for Birmingham Hip Resurfacing patients unless they report borderline or unacceptable hip function at two years, are female, are overweight, or received a bone graft during surgery. Cite this article: Bone Joint J 2019;101-B:1431–1437

Background. Prior research has shown that depression negatively impacts outcomes after total hip arthroplasty (THA); however, arthroplasty patients may also have depressive symptoms without an established diagnosis. The purpose of this study was to determine whether the Patient Health Questionnaire-2 (PHQ-2), a two-question depression screener, correlates with joint-specific symptom improvement after primary THA. Methods. This was a prospective cohort study. Patients completed the PHQ-2 and the Hip Disability and Osteoarthritis Outcome Score - Joint Replacement (HOOS-JR) prior to THA, with follow-up at 6 weeks and 6 months. An a priori power analysis determined a sample size of 31 would detect an effect size of 0.5 with a power of 0.80. We used previously established minimum clinically important difference (MCID) values for HOOS-JR. Continuous variables were analyzed with t-tests or Mann-Whitney tests while categorical variables were analyzed with Chi square or Fisher exact tests. Results. 77 patients were enrolled. 23 (30%) had a PHQ-2 of 3 or higher, indicating a high likelihood of depression. HOOS-JR scores were lower in the high PHQ-2 group at baseline and at six weeks (p<0.05). The two groups were equally likely to reach MCID at six weeks and six months, and there was no significant difference between absolute HOOS-JR scores at six months. Discussion. Patients with greater depressive symptoms have an equal likelihood of achieving MCID after THA, but worse absolute pain and function at baseline and six weeks after surgery. Administering the PHQ-2 may help surgeons better counsel their patients as to what to expect from surgery. Targeted mental health treatment perioperatively could allow these patients to achieve an even greater improvement in their long-term outcomes

The decision to undertake THA in a child is complex and surgery challenging. Pre-operatively patients' typically have significant pain and mobility restriction. Little is published on the functional gains after THA in this group. The aim of this study was therefore to measure the impact THA had on the PROMS in our young patients undergoing THA, to determine QoL improvement. This was a prospective, consecutive cohort study of patients under the age of 17 years undergoing THA by a single surgeon in a tertiary referral centre. Patient electronic notes, radiographs, and PROMS (EQ5D-Y, Oxford Hip Score (OHS) and modified Harris Hip Score (mHHS)) were reviewed. 12 children (8 females and 4 males) underwent THA before their 17th birthday, with 5 undergoing bilateral operations (17 THA total). The mean age was 14.6 years (10.75–16.9) and mean follow-up 1.5 years. Nine of the THA were undertaken for congenital syndromes, 4 for AVN, 2 for Perthe's disease and 1 for dysplasia and idiopathic chondrolysis. The mean pre-operative OHS was 15 (1–33) improving to 31 (19–39) at 6-weeks, 44 (42–46) at a year and 48 (47–48) at 3 years. mHHS improved from a pre-operative mean of 25 (0–56) to 60 (37–92) at 6-weeks, 65 (38–84) at a year and 91 (91) at 3 years. The EQ-VAS mean score pre-operatively was 35 (8–100) improving at 6-weeks to 73 (55–96), 84 (76–96) at a year and 92 (76–100) at 3 years. All patients achieved MCID or higher for OHS. 6 patients were wheelchair users preop. All patients were independent walkers at follow-up. There were no complications. THA in children is safe and leads to a significant positive impact on QoL as measured with validated PROMS scores. Wheelchair users can reliably gain independent walking. Further follow-up is required understand the long-term outcomes

Introduction. The direct anterior approach (DAA) for total hip arthroplasty (THA) has gained popularity in recent years. Potential advantages over other surgical approaches include less postoperative pain, fewer postoperative precautions, and quicker early recovery. It is most commonly performed in the supine position with traction tables or table mounted bone hooks to facilitate exposure. In this study, we describe a reproducible surgical technique for DAA THA in the lateral decubitus position with use of standard THA equipment and report on our results and learning curve. Methods. A prospectively collected hip repository was queried for all primary THA DAA performed in the lateral position by a single surgeon over a 4-year period from the surgeon's first case utilizing the technique. Retrospective chart review was performed to identify complications and revisions. Modified Harris Hip Score (mHHS) was collected pre-operatively and again at 1-year post-operative. Radiographic parameters including were measured on the 1-year postoperative radiographs. Results. Three hundred forty-one hips were identified in patients over 18 years of age with 337 hips meeting our inclusion/exclusion criteria. A total of 257 hips (76%) had a minimum of 1-year follow-up. 212 of 225 hips (94%) with available mHHS data achieved MCID, defined as mHHS change of > 8. Mean surgical time was 88 ± 16 minutes. Radiographic evaluation demonstrated reproducible results with mean radiographic side to side leg length discrepancy of 2.6 ± 5.9mm and femoral offset difference of 0.2 ± 4.9mm. Among patients with adequate postoperative radiographs, 234 of 243 (96%) had acetabular component positions within Lewinnick's safe zone. 3 hips (0.9%) required revision THA within the first year postoperatively. There were no dislocations and there was no learning curve detected in terms of operative time, blood loss, complication rate or acetabular component position. Discussion. Critics of DAA THA cite its long learning curve with increased risk of complications as an argument against its widespread use. In this study, we have described a safe and efficient technique for performing THA via the DAA in the familiar lateral decubitus with the use of a standard operating table, positioning devices and THA instrumentation. Our results demonstrate excellent acetabular component placement and low rates of complications within the first postoperative year. Conclusion. DAA THA can be performed safely and efficiently in the lateral decubitus position without a specialized table or instrumentation. Surgeon familiarity with patient position and instruments using the technique presented here may be associated with a shorter procedural learning curve