Most hip replacements are performed in an in-patient setting; however, there has been a shift in recent years in Canada towards doing more on an outpatient basis. In 2021–2022, 15.6% of hip replacements were performed as day surgeries compared to 0.7% in 2018–2019. This analysis will assess patient reported outcome measures of patients who had inpatient versus outpatient hip replacement surgery between 2018 and 2021. We analysed a retrospective sample of 4917 adult patients who had an elective primary unilateral hip replacement. Preoperative and three-month postoperative PROMs were completed - the Oxford Hip Score, EQD5L and patient satisfaction with the outcome were recorded. Patients who had an outpatient procedure were matched 1:1 with patients who are admitted to hospital for surgery based on age, sex and pre-COVID versus the COVID (March 15, 2020 as the start). Preoperative PROMs and Charlson Comorbidity Index were collected. T-tests and chi-square tests were used to assess the differences. The inpatient group on average was older, female and had a lower preoperative PROMs score and more comorbidities than the outpatient group. With cohort matching the sample consisted of 1244 patients. The inpatient and outpatient groups have similar Oxford scores, postoperative EQ-5D-5L scores and the proportion satisfied with their surgical results. The Oxford postoperative score was slightly higher in the outpatient group compared to the inpatient group; however, this is not clinically significant. We observed that outpatient protocols have no difference in patient satisfaction, self-reported functional outcomes and self-reported health-related quality of life three months after a hip replacement. Day surgery protocols represented potential solution to the challenges caused by the expected increase in demand for hip replacements. Our results demonstrated that patients do well clinically with day surgery procedures and there does not appear to be any detrimental effect on PROMs

Primary total joint arthroplasty (TJA) is an increasingly common and safe way of treating joint disease. Robust preoperative assessment improved intraoperative techniques and holistic rehabilitation contribute to an uneventful postoperative period. Despite there being evidence against the utility of postoperative blood tests, it is still often part of routine practice. We aim to evaluate the usefulness of these tests by investigating their incidence following TJA as well as identifying preoperative risk factors for abnormal blood test results postoperatively especially pertaining to anaemia and acute kidney injury (AKI). This is a retrospective cohort study of patients who had elective TJA between January and December 2019 at a tertiary centre. An independent student's t-test and Fisher's exact test was used to compare variables between the normal and abnormal postoperative results groups. An analysis of variance (ANOVA) was performed to identify risk factors for an abnormal blood test result. Analyses of receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to determine cut off values that could be suggestive of abnormal test results postoperatively. The study included 2721 patients with a mean age of 69 of which 46.6% were males. Abnormal postoperative bloods were identified in 444 (16.3%) patients. We identified age (≥65 years), female gender, ASA ≥ 3 as risk factors for developing abnormal postoperative blood tests. Preoperative haemoglobin (≤ 127 g/dL), haematocrit (≤ 0.395L/L) and potassium (≤ 3.7 mmol/L) were noted as cut-offs that could be predictive of postoperative anaemia or AKI respectively. The costs outweigh the benefits of ordering routine postoperative blood tests in TJA patients. Clinicians should risk stratify their patients and have a lower threshold for ordering blood tests in patients with one or more of the risk factors we have identified. These risk factors are age (≥65 years), females, ASA ≥ 3, preoperative haemoglobin (≤ 127 g/L), haematocrit (≤ 0.395L/L), and potassium (≤ 3.7 mmol/L)

Periprosthetic joint infections (PJIs) centers are garnering the attention of different arthroplasty surgeons and practices alike. Nonetheless, their value has yet to be proven. Therefore, we evaluated weather PJI centers produce comparable outcomes to the national average of THA PJIs on a national cohort. We performed a retrospective review of patient data available on PearlDiver from 2015 – 2021. PJI THA cases were identified through ICD-10 and CPT codes. Patients treated by 6 fellowship trained arthroplasty surgeons from a PJI center were matched based on age, gender, Charlson Comorbidity Index and Elixhauser comorbidity index at a 1:1 ratio to patients from the national cohort. Compared outcomes included LOS, ED visits, number of patients readmitted, total readmissions. Sample sized did not allow the evaluation of amputation, fusion or explantation. Normality was tested through the Kolmogorov-Smirnov test. And comparisons were made with Students t-tests and Chi Square testing. A total of 33,001 THA PJIs and were identified. A total of 77 patients were identified as treated by the PJI center cohort and successfully matched. No differences were noted in regard to age, gender distribution, CCI or ECI (p=1, 1, 1 and 0.9958 respectively). Significant differences were noted in mean LOS (p<0.43), number of patients requiring readmissions (p=0.001) and total number of readmission events (p<0.001). No difference was noted on ED visits. Our study demonstrates that a PJI for THA cases may be beneficial for the national growing trend of arthroplasty volume. Future data, that allows comparison of patient's specific data will allow for further validation of PJI centers and how these can play a role in helping the national PJI growing problem

There is paucity of reliable data examining the treatment pathway for hip replacements over the life of the patient in terms of risk of revision and re-revisions. We did a retrospective observational registry-based study of the National Joint Registry, using data on hip replacements from all participating hospitals in England and Wales, UK. We included data on all first revisions, with an identifiable primary procedure, with osteoarthritis as the sole indication for the original primary procedure. Kaplan-Meier estimates were used to determine the cumulative probability of revision and subsequent re-revision after primary hip replacement. Analyses were stratified by age and gender, and the influence of time from first to second revision on the risk of further revision was explored. Between 2003, and 2019, there were 29 010 revision hip replacements with a linked primary episode. Revision rates of revision hip replacements were higher in patients younger than 55 years than in older age groups. After revision of primary total hip replacement, 21·3% (95% CI 18·6–24·4) of first revisions were revised again within 15 years, 22·3% (20·3–24·4) of second revisions were revised again within 7 years, and 22·3% (18·3–27·0) of third revisions were revised again within 3 years. After revision of hip resurfacing, 23·7% (95% CI 19·6–28·5) of these revisions were revised again within 15 years, 21·0% (17·0–25·8) of second revisions were revised again within 7 years, and 19·3% (11·9–30·4) of third revisions were revised again within 3 years. A shorter time between revision episodes was associated with earlier subsequent revision. Younger patients are at an increased risk of multiple revisions. Patients who undergo a revision have a steadily increasing risk of further revision the more procedures they undergo, and each subsequent revision lasts for approximately half the time of the previous one

This study aimed to verify the hypothesis that an antibiotic loaded hydrogel, defensive antimicrobial coating (DAC), reduces overall complication and infection rates when used for high-risk primary and revision total hip arthroplasty (THA). This was a retrospective study matched cohort study of 238 patients, treated with cementless implants with and without DAC. A sub-group analysis of patients undergoing 2nd stage revision THA for prosthetic joint infection (PJI) was also conducted. Re-infection rates within 2 years, complications necessitating surgical intervention and radiographic analysis for aseptic loosening was assessed. The mean age was 68.3±11.5 years, with 39 (32.8%) Macpherson class A, 64 (53.8%) class B and 16 (13.4%) class C patients. 4 (3.4%) patients in the DAC group developed complications including 1 PJI and 1 delayed wound healing, while 13 (10.9%) patients in the control group developed complications including 5 PJIs and 3 delayed wound healing (p=0.032). PJI rates (p=0.136) and delayed wound healing rates (p=0.337) were not statistically significant. For 2nd stage revision THA for PJI there were 86 patients in the DAC group and 45 in the control group. 1 (1.2%) patient in the DAC group developed complications with no recurrences of infection or delayed wound healing, while 10 (22.2%) patients in the control group developed complications including 4 recurrent PJI and 1 delayed wound healing (p=0.003). Recurrent PJI rates were statistically significant (p=0.005) while delayed wound healing rates were not (p=0.165). Patients treated with DAC also had lower rates of aseptic loosening (0% vs 6.7%; p=0.015). Antibiotic impregnated hydrogel coatings on cementless implants showed decreased complication rates after complex primary or revision THA. In 2nd stage revision THA for PJI, it was associated with reduced risk of re-infection and aseptic loosening

Until today it is unknown whether preservation of the joint capsule positively affects patient reported outcome (PROs) in DAA-THA. A recent RCT found no clinical difference at 1 year. Since 2015 we preserve the capsule suture it at the end. We here evaluate whether this change had any effect on PROs and revisions, 2 years post-operatively. Two subsequent cohorts operated by the senior author were compared. The capsule was resected in the first cohort (January 2012 – December 2014) and preserved in the second cohort (July 2015 – December 2017). No other technical changes have been introduced between the two cohorts. Patient demographics, Charlson Comorbidity Index (CCI), and surgical data were collected from our clinical information system. 2-years PROs questionnaires (OHS, COMI Hip) were obtained. Data was analyzed with generalized multiple regression analysis. 430 and 450 patients were included in the resected and preserved cohorts, respectively. Demographics, CCI surgical time and length of stay were equal in both groups. Blood loss was less in the preserved cohort (p<.05). Four patients had a revision (1 vs 3, n.s.). Once corrected for demographics, capsule preservation had significant worse PROs: +0.24 COMI (p<.001) and −1.6 OHS points (p<.05), however, effects were much smaller than the minimal clinically important difference (0.95 and 5 respectively). The date of surgery (i.e. surgeon's age) was not a significant factor. In this large retrospective study, we observed statistically significant, but probably clinically not relevant, worse PROs with capsule preservation. It might be speculated that the not resected hypertrophied capsule could have caused this difference

Periprosthetic joint infection (PJI) causes significant morbidity. Methicillin sensitive Staphylococcus Aureus (MSSA) is the most frequent organism, and the majority are endogenous. Nasal MSSA colonisation is a proven risk factor for S. aureus infection. Decolonisation reduces PJIs but there is a paucity of evidence comparing treatments. Aims; compare 3 nasal decolonisation treatments at (1) achieving MSSA decolonisation, (2) preventing PJI.

Our hospital trust introduced MSSA screening and decolonisation prior to hip and knee arthroplasty in 2010. Data was prospectively collected since 2013, including all MSSA carriers, decolonisation treatment received, MSSA status at time of surgery and all PJIs. Prior to 2017 MSSA carriers received nasal mupirocin or neomycin, from August 2017 until August 2019 nasal octenidine was used.

During the study period 15,958 primary hip and knee replacements were performed. 3,200 (20.1%) were MSSA positive at preoperative screening and received decolonisation treatment, 698 mupirocin, 1,210 neomycin and 1,221 octenidine. Mupirocin (89.1%) and neomycin (90.9%) were more effective at decolonisation than octenidine (50.0%, P<0.0001). There was no difference in S. aureus PJI rates (P=0.452). Of those negative at original screening 9.1% were positive on the day of surgery (1,164/12,758).

MSSA decolonisation is an effective method to decrease PJI rates but there is little research into the best treatment. Both mupirocin and neomycin are more effective than octenidine at achieving MSSA decolonisation. There was poor correlation between the MSSA status after treatment and PJI rates. There is debate if treatment should be targeted by screening or if all patients she be treated without screening. Global decolonisation without screening is supported by the 26.7% of carriers that were negative at original screening in our study.

Further research is needed comparing decolonisation treatments to reduce PJI rates and avoid the risk of drug resistance.

There is still no clear consensus regarding which cup position might provide better functional performance for developmental dysplasia of the hip (DDH). This study aimed to evaluated the feasibility and efficacy of acetabular mirroring reconstruction for DDH in total hip arthroplasty (THA).

The study reviewed 96 patients (96 hips) with unilateral Crowe type-II/III DDH undergoing either visualized navigation-assisted mirroring reconstruction with augment according to the rotation center and biomechanical structure of the contralateral normal hips (Mirroring group, 51 hips) or high hip center reconstruction (HHC group, 45 hips) in THA from 2020 to 2023. The functional and radiographic results were analyzed between the groups during a mean follow-up period of 27.5 and 28.9 months (a minimum follow-up of 12 months).

The Harris hip score at the last follow-up significantly improved in both groups, while it was significantly higher in the mirroring group (P<0.001). In the HHC group, the rotation center height and greater trochanter height were significantly increased in the affected hip (P<0.001; P<0.001) and the abductor lever arm was significantly decreased in the affected hip compared to that in the contralateral normal hip (P<0.001), whereas in the mirroring group no significant statistical differences were observed between two sides. The limping occurred in 7 patients (13.7%) in the mirroring group and 14 patients (31.1%) in the HHC group (P=0.040). A multiple logistic regression demonstrated mirroring reconstruction could reduce the incidence of postoperative limping (P=0.020).

Both mirroring and HHC reconstruction could improve the functional performance of THA, whereas mirroring reconstruction could offer superior biomechanical results and gait improvement as compared with HHC reconstruction, meeting the higher requirements of functional recovery.

Due to limitations of existing pharmacological therapies for the management of chronic pain in osteoarthritis (OA), surgical interventions remain a major component of current standard of care, with total joint replacements (TJRs) considered for people who have not responded adequately to conservative treatment. This study aimed to quantify the economic burden of moderate-to-severe chronic pain in patients with OA in England prior to TJR. A retrospective, longitudinal cohort design was employed using Clinical Practice Research Datalink GOLD primary care data linked to Hospital Episode Statistics secondary care data in England. Patients (age ≥18 years) with an existing OA diagnosis of any anatomical site (Read/ICD-10) were indexed (Dec-2009 to Nov-2017) on a moderate-to-severe pain event (which included TJR) occurring within an episode of chronic pain. 5-year TJR rates from indexing were assessed via Kaplan-Meier estimates. All-cause healthcare resource utilisation and direct medical costs were evaluated in the 1–12 and 13–24 months prior to the first TJR experienced after index. Statistical significance was assessed via paired t-tests. The study cohort comprised 5,931 eligible patients (57.9% aged ≥65 years, 59.2% female). 2,176 (36.7%) underwent TJR (knee: 54.4%; hip: 42.8%; other: 2.8%). The 5-year TJR rate was 45.4% (knee: 24.3%; hip: 17.5%; other: 6.8%). Patients experienced more general practitioner consultations in 1–12 months pre-TJR compared with 13–24 months pre-TJR (means: 12.13 vs. 9.61; p<0.0001), more outpatient visits (6.68 vs. 3.77; p<0.0001), more hospitalisations (0.74 vs. 0.62; p=0.0032), and more emergency department visits (0.29 vs. 0.25, p=0.0190). Total time (days) spent as an inpatient was higher in 1–12 months pre-TJR (1.86 vs. 1.07; p<0.0001). Mean total per-patient cost pre-TJR increased from £1,771 (13–24 months) to £2,621 (1–12 months) (p<0.0001). Resource-use and costs incurred were substantially greater in the 12 months immediately prior to TJR, compared with 13–24 months prior. Reasons for increased healthcare and economic burden in the pre-TJR period deserve further exploration as potential targets for efforts to improve patient experience and efficiency of care

Aims. Natural Language Processing (NLP) offers an automated method to extract data from unstructured free text fields for arthroplasty registry participation. Our objective was to investigate how accurately NLP can be used to extract structured clinical data from unstructured clinical notes when compared with manual data extraction. Methods. A group of 1,000 randomly selected clinical and hospital notes from eight different surgeons were collected for patients undergoing primary arthroplasty between 2012 and 2018. In all, 19 preoperative, 17 operative, and two postoperative variables of interest were manually extracted from these notes. A NLP algorithm was created to automatically extract these variables from a training sample of these notes, and the algorithm was tested on a random test sample of notes. Performance of the NLP algorithm was measured in Statistical Analysis System (SAS) by calculating the accuracy of the variables collected, the ability of the algorithm to collect the correct information when it was indeed in the note (sensitivity), and the ability of the algorithm to not collect a certain data element when it was not in the note (specificity). Results. The NLP algorithm performed well at extracting variables from unstructured data in our random test dataset (accuracy = 96.3%, sensitivity = 95.2%, and specificity = 97.4%). It performed better at extracting data that were in a structured, templated format such as range of movement (ROM) (accuracy = 98%) and implant brand (accuracy = 98%) than data that were entered with variation depending on the author of the note such as the presence of deep-vein thrombosis (DVT) (accuracy = 90%). Conclusion. The NLP algorithm used in this study was able to identify a subset of variables from randomly selected unstructured notes in arthroplasty with an accuracy above 90%. For some variables, such as objective exam data, the accuracy was very high. Our findings suggest that automated algorithms using NLP can help orthopaedic practices retrospectively collect information for registries and quality improvement (QI) efforts. Cite this article: Bone Joint J 2020;102-B(7 Supple B):99–104

Introduction. Despite an ageing population and a rise in the number of joint replacements being performed, the mean age of patients undergoing surgery remains static. One explanation for this is continued concern over the risks of performing surgery on the very elderly. The Elective Orthopaedic Centre, Epsom has an established patient reported outcome measures (PROMs) programme into which all patients are routinely enrolled. Post-operative complications, Oxford scores and Euro-Quol (EQ5-D) are collected to the second post-operative year. Methods and Results. We retrospectively reviewed our data set for a cohort of nonagenarians undergoing primary total hip replacement (THR) between April 2008 and October 2011. Post-operative complications, mortality rates and functional outcomes were compared to those of a time matched 70–79 year old cohort. Only patients with a primary diagnosis of osteoarthritis were included whereas an exclusion criterion consisted of patients undergoing revision surgery, simultaneous bilateral replacements or conversion from a dynamic hip screw. We identified 38 nonagenarian patients (12 men and 26 women), with a mean age of 92.18 (90–99) and the control group consisted of 55 patients (21 men and 34 women), with a mean age of 74.69 (70–79). We found that nonagenarians requiring a THR presented with lower pre-operative Oxford Hip Score (OHS) (p=0.02) but made a greater improvement in the first post-operative year than the younger cohort (p=0.040). The nonagenarians had a greater risk of requiring a blood transfusion following THR (p= 0.0265; CI 1.11 to 5.75), and also required a longer stay than their younger counterparts (p=0.001). Mortality rates were higher in the nonagenarian cohort, but these were in keeping with the life expectancy projections identified by the Office for National Statistics (ONS). Conclusion. In conclusion, we identified that over a 2 year period, nonagenarians achieved the same functional outcome and satisfaction rates following a THR as 70–79 year olds

Introduction. We investigated predictors of poor outcomes following metal-on-metal hip arthroplasty (MoMHA) revision surgery performed for adverse reactions to metal debris (ARMD), to help inform the revision threshold and type of reconstruction. Patients and Methods. A retrospective cohort study was performed involving 346 MoMHAs revised for histologically confirmed ARMD at two specialist centres (245=hip resurfacing, 101=total hip arthroplasty). Numerous preoperative (blood metal ions and imaging) and intraoperative (findings, and components removed/implanted) factors were used to predict poor outcomes. Poor outcomes were postoperative complications (including re-revisions), 90-day mortality, and poor Oxford Hip Scores (<27/48). Multivariable logistic regression models for predicting poor outcomes were developed using stepwise selection methods. Results. Cumulative implant survival rate seven-years after ARMD revision was 87.0% (95% CI=81.0%-91.2%). Poor outcomes occurred in 39% (n=135). Shorter time (under four-years) from primary to revision surgery (odds ratio (OR)=2.12, CI=1.00–4.46) was the only preoperative predictor of poor outcomes. Pre-revision metal ions and imaging did not influence outcomes. Single-component revisions increased the risk of poor outcomes (acetabular or femoral vs. all component revisions; OR=2.99, CI=1.50–5.97). Intraoperative factors reducing the risk of poor outcomes included the posterior approach (OR=0.22, CI=0.10–0.49), revision head sizes ≥36mm (vs. <36mm: OR=0.37, CI=0.18–0.77), ceramic-on-polyethylene (OR vs. ceramic-on-ceramic=0.30, CI=0.14–0.66) and metal-on-polyethylene revision bearings (OR vs. ceramic-on-ceramic=0.37, CI=0.17–0.83). Discussion. This large cohort study demonstrated 39% of patients experience poor outcomes following MoMHA revision for ARMD. This information will help surgeons when counselling patient's pre-revision about the expected prognosis. No threshold exists for recommending ARMD revision, therefore surgeons must make decisions on an individual case basis. However, surgeons can make intraoperative decisions that influence outcomes following ARMD revision. Conclusion. We recommend optimal outcomes following ARMD revision may be achieved if surgeons use the posterior approach, revise all MoMHA components, and use ≥36mm ceramic-on-polyethylene or metal-on-polyethylene articulations

Introduction. Patients with pre-existing dementia are more susceptible to hip fracture due to various risk factors such as age, decreased activity leading to sarcopenia and osteoporosis, Vitamin D deficiency and presence of Apolipoprotein gene. The mortality associated with dementia and fracture neck of femurs was thought to be 2.3 times more than that of patients with intact cognitive function. The aim of this study is to assess the mortality of patients at 28 days, 4 months and one year after undergoing surgery for fracture neck of femurs. Methods. A retrospective study of 184 patients admitted with fracture neck of femur and had dementia for a period from April 2014 to August 2016 were carried out. The patient demographics, AMT score, pre-operative co-morbidities, perioperative mortality and one year mortality were analysed. Results. A total no. of 1007 patients was admitted with fracture neck of femurs during the study period. 184 patients were found to have pre fracture dementia. The mean age was87.088 years (Range 64–101). There was 42 males and 142 females. The average ASA grade was 2–3. 99 patients (53.8%) had Alzheimer's disease, 50 patients (27%) had vascular dementia and 35 patients (19.2%) had other types of dementia.94 patients (51%) had more than one co-morbidity. The average AMT score was 0.66(normal range 0–10). The total number of patients died was 114(62%). The overall mortality at 28 days was 24 %(44 patients=0.0001), 4 months was 46 %(84 patients) and one year was 62 %(114 patients, p=0.0001). In 90(49%) patients who had only dementia and no other co-morbidities(ASA grade 1–2) the mortality at 28 days was 20% (p=0.0051), 4 months was 40% and at one year 61%(p=0.0001). Conclusion. In our study we found that the overall mortality in patients with dementia and fracture neck of femurs is 62% and the perioperative mortality rate was 24%. The peri-operative mortality rate was 20% in patients with pure dementia. The mortally rate in dementia with fracture neck of femurs patients was far more than what is noted in the literature

Patients need to know the benefits, risks and alternatives to any proposed treatment. Surgeons discussing the risk of a revision procedure becoming necessary, after a hip replacement can draw upon the orthopaedic literature and arthroplasty registries for long-term implant survival. However, early revision is required in a minority of cases. We have investigated the probability for revision hip replacement patients in terms of time-point and indication for revision.

Of the 9,411 Primary Total Hip Replacements (THR), undertaken by 22 surgeons, over an eleven-year period, between January 2004 and March 2015, 1.70% (160) were subsequently reported to the National Joint Registry (NJR) as revised. Each revision case was reviewed under the supervision of senior hip specialist consultants. The modes of failure of were identified through clinical, laboratory and imaging (x-rays, CT, MRI and Isotope scans) studies.

The revision rate for THRs was 0.58% in the first year. This was statistically higher than all subsequent years, P-Value <0.001. There was no statistical difference between any pair of subsequent years. Thereafter, the average revision rate was 0.30% per annum. The odds ratio for revision during the first post–operative year against the subsequent year average was 1.67.

The indications for the early hip revisions in the first three years were infection, dislocation and peri-prosthetic fracture. The data from this study can help better inform patients of the revision rates after a primary THR and allow surgeons to develop implant surveillance strategies among high-risk patients.

There is a high risk of the development of avascular necrosis of the femoral head and nonunion after the treatment of displaced subcapital fractures of the femoral neck in patients aged < 50 years. We retrospectively analysed the results following fixation with two cannulated compression screws and a vascularised iliac bone graft. We treated 18 women and 16 men with a mean age of 38.5 years (20 to 50) whose treatment included the use of an iliac bone graft based on the ascending branch of lateral femoral circumflex artery. There were 20 Garden grade III and 14 grade IV fractures. Clinical and radiological outcomes were evaluated. The mean follow-up was 5.4 years (2 to 10). In 30 hips (88%) union was achieved at a mean of 4.4 months (4 to 6). Nonunion occurred in four hips (12%) and these patients had a mean age of 46.5 years (42 to 50) and underwent revision to a hip replacement six months after operation. The time to union was dependent on age with younger patients achieving earlier union (p < 0.001). According to the Harris hip score which was available for 27 of the 30 hips with satisfactory union, excellent results were obtained in 15 (score ≥ 90 points), fair in ten (score 80 to 90 points), and poor in two hips (≤ 80 points). One patient aged 48 years developed avascular necrosis of femoral head six years after operation and underwent total hip replacement. The management of displaced subcapital fractures of the femoral neck, in patients aged <  50 years, with two cannulated compression screws and an iliac bone graft based on the ascending branch of lateral femoral circumflex artery, gives satisfactory results with a low rate of complication including avascular necrosis and nonunion. Cite this article: Bone Joint J 2014;96-B:1024–8

Introduction

Magnetic resonance arthrogram (MRA) is the investigation of choice in young adults with symptoms of femero acetabular impingement. The aim of the study is to assess the accuracy of MRA when correlated with surgical findings on hip arthroscopy.

INTRODUCTION

Dislocation is a major complication post total hip replacement (THR) and a common cause for revision. Jameson et al (2012) studied 35,000 cemented Exeter (Stryker) THRs demonstrating the risk of revision was significantly influenced by the acetabular component design. This led 3 surgeons in a single hospital group to make a mass move from using the hooded Exeter Low Profile (LP) cup to the better performing Contemporary Flanged (CF) component. The purpose of this study was to show whether this change was associated with a fall in dislocation rates.

Aims. The Single Assessment Numerical Evalution (SANE) score is a pragmatic alternative to longer patient-reported outcome measures (PROMs). The purpose of this study was to investigate the concurrent validity of the SANE and hip-specific PROMs in a generalized population of patients with hip pain at a single timepoint upon initial visit with an orthopaedic surgeon who is a hip preservation specialist. We hypothesized that SANE would have a strong correlation with the 12-question International Hip Outcome Tool (iHOT)-12, the Hip Outcome Score (HOS), and the Hip disability and Osteoarthritis Outcome Score (HOOS), providing evidence for concurrent validity of the SANE and hip-specific outcome measures in patients with hip pain. Methods. This study was a cross-sectional retrospective database analysis at a single timepoint. Data were collected from 2,782 patients at initial evaluation with a hip preservation specialist using the iHOT-12, HOS, HOOS, and SANE. Outcome scores were retrospectively analyzed using Pearson correlation coefficients. Results. Mean raw scores were iHOT-12 67.01 (SD 29.52), HOS 58.42 (SD 26.26), HOOS 86.85 (SD 32.94), and SANE 49.60 (SD 27.92). SANE was moderately correlated with the iHOT-12 (r = -0.4; 95% CI -0.35 to -0.44; p < 0.001), HOS (r = 0.57; 95% CI 0.53 to 0.60; p < 0.001), and HOOS (r = -0.55; 95% CI -0.51 to -0.58; p < 0.001). The iHOT-12 and HOOS were recorded as a lower score, indicating better function, which accounts for the negative r values. Conclusion. This study was the first to investigate the relationship between the SANE and the iHOT-12, HOS, and HOOS in a population of patients with hip pain at the initial evaluation with an orthopaedic surgeon, and found moderate correlation between SANE and the iHOT-12, HOS, and HOOS. The SANE may be a pragmatic alternative for clinical benchmarking in a general population of patients with hip pain. The construct validity of the SANE should be questioned compared to legacy measures whose content validity has been more rigorously investigated. Cite this article: Bone Jt Open 2024;5(10):904–910

Aims. Iliopsoas impingement occurs in 4% to 30% of patients after undergoing total hip arthroplasty (THA). Despite a relatively high incidence, there are few attempts at modelling impingement between the iliopsoas and acetabular component, and no attempts at modelling this in a representative cohort of subjects. The purpose of this study was to develop a novel computational model for quantifying the impingement between the iliopsoas and acetabular component and validate its utility in a case-controlled investigation. Methods. This was a retrospective cohort study of patients who underwent THA surgery that included 23 symptomatic patients diagnosed with iliopsoas tendonitis, and 23 patients not diagnosed with iliopsoas tendonitis. All patients received postoperative CT imaging, postoperative standing radiography, and had minimum six months’ follow-up. 3D models of each patient’s prosthetic and bony anatomy were generated, landmarked, and simulated in a novel iliopsoas impingement detection model in supine and standing pelvic positions. Logistic regression models were implemented to determine if the probability of pain could be significantly predicted. Receiver operating characteristic curves were generated to determine the model’s sensitivity, specificity, and area under the curve (AUC). Results. Highly significant differences between the symptomatic and asymptomatic cohorts were observed for iliopsoas impingement. Logistic regression models determined that the impingement values significantly predicted the probability of groin pain. The simulation had a sensitivity of 74%, specificity of 100%, and an AUC of 0.86. Conclusion. We developed a computational model that can quantify iliopsoas impingement and verified its accuracy in a case-controlled investigation. This tool has the potential to be used preoperatively, to guide decisions about optimal cup placement, and postoperatively, to assist in the diagnosis of iliopsoas tendonitis. Cite this article: Bone Jt Open 2023;4(1):3–12

Aims. Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects. Methods. We performed a retrospective review at a single institution of patients undergoing revision THA by a single surgeon. We identified 49 consecutive patients with large acetabular defects where the biphasic BGS was applied, with no other products added to the BGS. After placement of metallic acetabular implants, the BGS was injected into the remaining bone defects surrounding the new implants. Patients were followed and monitored for functional outcome scores, implant fixation, radiological graft site remodelling, and revision failures. Results. Mean follow-up was 39.5 months (36 to 71), with a significant improvement in post-revision function compared to preoperative function. Graft site remodelling was rated radiologically as moderate in 31 hips (63%) and strong in 12 hips (24%). There were no cases of complete graft site dissolution. No acetabular loosening was identified. None of the patients developed clinically significant heterotopic ossification. There were twelve reoperations: six patients developed post-revision infections, three experienced dislocations, two sustained periprosthetic femur fractures, and one subject had femoral component aseptic loosening. Conclusion. Our series reports bone defect restoration with the sole use of a biphasic injectable BGS in the periacetabular region. We did not observe significant graft dissolution. We emphasize that successful graft site remodelling requires meticulous recipient site preparation. Cite this article: Bone Jt Open 2022;3(12):991–997