Identification of Factors Associated with Disease Progression in the Contralateral Hip of Patients with Symptomatic Femoroacetabular Impingement. (139)

Objectives: Femoroacetabular Impingement (FAI) is one of the most common causes of hip osteoarthritis. Nevertheless, the factors contributing to symptom development and FAI disease progression are poorly understood. The purpose of this study was to (1) investigate rates of symptom development in the contralateral hip of patients with FAI at mid-term follow-up, and (2) identify predictors of disease progression (symptom development) in the contralateral hip. Methods: This prospective study included 179 patients undergoing ipsilateral FAI surgery with no history of previous contralateral hip surgery. In the current study, the contralateral hip was assessed at minimum 5 year follow-up. Symptoms (defined as moderate pain) and the need for surgery were monitored over the study course. Statistical analysis compared patient and FAI imaging characteristics of patients developing symptoms to those who remained asymptomatic. Results: A total of 146 hips (81.5%) were included at a mean 6.7 years of follow-up. Thirty-nine (26.7%) presented with symptoms in the contralateral hip, while an additional 35 (23.9%) developed symptoms during the follow-up period. Twenty-Six (17.8%) progressed to surgery for their contralateral hip. Head-neck offset ratio (HNOR) on AP pelvis radiographs was significantly lower among hips that developed symptoms (0.16 vs. 0.15 p=0.03). Maximum alpha angle (p=0.41), lateral center edge angle (p=0.70), and crossover sign (p=0.12) were not predictive of symptoms. Patients with a UCLA activity score greater than 9 were less likely to develop symptoms (14% vs. 46%, p=0.081), but this was not statistically significant. The total arc of rotation in 90° of flexion (40.0° vs 50.8°, p=0.01) as well as external rotation at 900 of flexion (28.9° vs 36.6°, p=0.02) were decreased in hips developing symptoms. Internal rotation in flexion was not significantly decreased in symptomatic patients (11.1° vs 14.2°, p=0.11). Kaplan Meier survival analysis demonstrated 53% and 45% of patients remaining asymptomatic at 5 and 8 year time points (Figure). Conclusions: At a mean follow-up of 6.7 years, significant symptoms in the contralateral hip of patients with FAI are present in 50.7% of patients, while 49.3% remain asymptomatic or minimally symptomatic. We identified unique radiographic and physical exam findings that are associated with symptom development in patients with FAI. Specifically, decreased hip rotation arc and decreased HNOR were strongly associated with disease progression and may represent important factors for future risk modeling in FAI patients.

Statistical analysis plan for a pragmatic phase III randomised controlled trial examining behaviour change physiotherapy intervention to increase physical activity following hip and knee replacements: the PEP-TALK trial

Background Total hip (THR) and total knee replacements (TKR) are two highly successful orthopaedic procedures that reduce pain for people with osteoarthritis. Previous evidence suggests that physical activity, at best, remains the same pre- to post-operatively, and in some instances declines. The PEP-TALK trial evaluates the effects of a group-based, behaviour change intervention on physical activity following a THR or TKR. Methods PEP-TALK is an open, phase III, pragmatic, multi-centre, parallel, two-arm, two-way superiority randomised controlled trial investigating the effectiveness of usual care plus a behaviour change therapy compared with usual care alone following primary THR or TKR. The primary outcome is the UCLA Activity Score at 12 months post-randomisation which will be analysed using a linear mixed effects model. Secondary outcomes measured at 6 months and 12 months after randomisation include the UCLA Activity Score, Lower Extremity Functional Scale, Oxford Hip/Knee Score, Numerical Rating Scale for Pain, Generalised Self-Efficacy Scale, Tampa Scale for Kinesiophobia, Hospital Anxiety and Depression Scale, EuroQoL EQ-5D-5L index and EQ-VAS and complications or adverse events. Full details of the planned analysis approaches for the primary and secondary outcomes, as well as the planned sensitivity analyses to be undertaken due to the COVID-19 pandemic, are described here. The PEP-TALK study protocol has been published previously. Discussion This paper provides details of the planned statistical analyses for the PEP-TALK trial. This is aimed to reduce the risk of outcome reporting bias and enhance transparency in reporting. Trial registration International Standard Randomised Controlled Trials database, ISRCTN Number: 29770908. Registered on October 2018.

IDENTIFICATION OF FACTORS ASSOCIATED WITH DISEASE PROGRESSION IN THE CONTRALATERAL HIP OF PATIENTS WITH SYMPTOMATIC FEMOROACETABULAR IMPINGEMENT

Introduction: Femoroacetabular Impingement (FAI) is one of the most common causes of hip osteoarthritis. Nevertheless, the factors contributing to symptom development and FAI disease progression are poorly understood. Hypothesis/Purpose: The purpose of this study was to (1) investigate rates of initial and subsequent symptom development in the contralateral hip of patients with FAI, and (2) identify predictors of disease progression (symptom development) in the contralateral hip. Methods: This prospective study included a minimum 5 year follow-up of the contralateral hip in 179 patients undergoing FAI surgery. Symptoms (moderate pain) were monitored over the study course. Univariate analysis compared patient and FAI imaging characteristics of patients developing symptoms to those who remained asymptomatic. Results: 146 patients (146 hips, 81.5%) were included (min 5 year, mean 6.7 years). Thirty-nine (26%) presented with symptoms in the contralateral hip while 34 (23%) developed symptoms. Head-neck offset ratio (HNOR) on AP pelvis radiographs was significantly lower among hips that developed symptoms (0.164 vs. 0.153 p=0.025). Maximum alpha angle (p=0.413), lateral center edge angle (p=0.704), and crossover sign (p=0.115) were not predictive of symptoms. Patients with a UCLA activity score greater than 9 were less likely to develop symptoms (14% vs. 46%, p=0.081), but this was not statistically significant. The total arc of rotation in extension (35.740 vs 45.140, p=0.012) and 900 of flexion (40.00 vs 50.800, p=0.009) as well as external rotation at 900 of flexion (28.940 vs 36.590, p=0.020) were decreased in hips developing symptoms. Internal Rotation in flexion was not significantly decreased in symptomatic patients (11.060 vs 14.20, p=0.113). Conclusions: We identified unique radiographic and physical exam findings that are associated with symptom development in patients with FAI. Specifically, decreased hip rotation arc and decreased HNOR were strongly associated with disease progression and may represent important factors for future risk modeling in FAI patients.

The short-term effectiveness and safety of second-generation patellofemoral arthroplasty and total knee arthroplasty on isolated patellofemoral osteoarthritis: a systematic review and meta-analysis

Background We aimed to compare second-generation patellofemoral arthroplasty (2G PFA) with total knee arthroplasty (TKA) in treating isolated patellofemoral osteoarthritis (PFOA) by assessing the percentages of revisions, complications, and patient-reported outcome measures (PROMs). Methods Studies that compared the outcomes of 2G PFA and TKA in the treatment of isolated PFOA were searched in electronic databases, including MEDLINE, Embase, and Web of Science. Two researchers independently identified eligible studies, extracted the data, and evaluated the quality of the literature. Pooled risk ratios (RRs) or weighted mean differences with 95% confidence intervals were calculated using either fixed or random effects models. Descriptive analysis was used when data could not be pooled. Results A total of six studies were included in the review. For the revision percentage and complications, there were no significant differences between 2G PFA and TKA (RR = 2.29, 95% CI 0.69–7.58, P = 0.17; RR = 0.56, 95% CI 0.23–1.40, P = 0.22, respectively). Second, the results demonstrated that the differences in the Oxford Knee Score (OKS) and the University of California, Los Angeles (UCLA) activity score between 2G PFA and TKA were not significant (WMD −4.68, 95% CI −16.32 to 6.97, p = 0.43; WMD 0.16, 95% CI −1.21 to 1.53, P = 0.82). The Knee Injury and Osteoarthritis Outcome Score (KOOS), the American Knee Society Score (AKSS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were presented in a narrative form due to methodological heterogeneity. Conclusion For isolated PFOA, 2G PFA demonstrated similar results to TKA with respect to the percentages of revisions, complications, and PROMs.

Patient-reported outcomes after primary or revision total hip arthroplasty: A propensity score-matched Asian cohort study

Background Few studies have compared patient-reported outcome measures (PROMs) between primary and revision total hip arthroplasty (THA). We investigated and compared PROMs between propensity score-matched primary and revision THA in an Asian cohort. Methods The Oxford Hip Score (OHS) and University of California-Los Angeles (UCLA) activity score, satisfaction score, and Short Form-12 Health Survey (SF-12) were compared between 110 primary and 110 revision THAs after propensity score matching. Multivariate analyses were performed to determine which factors, including patients’ demographics, indication for revision, and pre-operative PROMs, were associated with post-operative PROMs in the revision THA cohort. Results The revision THA cohort demonstrated significantly lower post-operative OHS, UCLA activity score, and satisfaction score (10% decrease on average) than those in the primary THA cohort (P < .05). The difference in SF-12 mental component summary measure (MCS) between the two cohorts was statistically insignificant (P = .24). In multivariate analysis for the revision THA cohort, lower post-operative UCLA activity score was significantly associated with higher BMI and lower pre-operative UCLA activity score (P < .05). Conclusion Revision THA was associated with a modest but significant decrease in physical PROMs as compared with primary THA. Pre-operative UCLA activity score significantly affected the post-operative physical outcome measures in the revision THA cohort. However, post-operative SF-12 MCS was comparable between the primary and revision THA cohorts.

Use of Preoperative Magnetic Resonance Imaging to Predict Clinical Outcomes After Core Muscle Injury Repair

Background: Core muscle injury (CMI), often referred to as a sports hernia or athletic pubalgia, is a common cause of groin pain in athletes. Imaging modalities used to assist in the diagnosis of CMI include ultrasound (US) and magnetic resonance imaging (MRI). Purpose: To determine if preoperative MRI findings predict clinical outcomes after surgery for CMI. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective cohort study was performed on a consecutive series of patients who were operatively treated for CMI by a single surgeon. CMI was diagnosed based on history, physical examination, and a positive US. In addition, all patients underwent a preoperative MRI. Patients were divided into 2 groups based on whether the MRI was interpreted as positive or negative for CMI. All patients underwent mini-open CMI repair. Patient-reported outcomes (PROs) were collected both pre- and postoperatively and included a visual analog scale (VAS) for pain, the University of California, Los Angeles (UCLA) activity score, and the modified Harris Hip Score. Results: A total of 39 hips were included in this study, of which 17 had a positive MRI interpretation for CMI (44%) and 22 had a negative MRI interpretation (56%). Mean age at the time of surgery was 35 years (range, 17-56 years), and mean follow-up was 21 months (range, 12-35 months). No significant difference was found between groups in mean age or time to follow-up. Patients in both groups demonstrated significant improvement from preoperative to most recent follow-up in terms of the UCLA activity score ( P < .05). VAS scores significantly improved for patients with a positive MRI interpretation ( P = .001) but not for those with a negative MRI interpretation ( P = .094). No significant difference on any PROs was found between groups at the most recent follow-up. Conclusion: Successful clinical outcomes can be expected in patients undergoing surgery for CMI diagnosed based on history, physical examination, and US. Patients with a preoperative MRI consistent with CMI may experience greater improvement in pain postoperatively, although MRI does not predict postoperative activity level in these patients.

Complications, mobility, and quality of life in ankle sarcoma patients

Aims The aims of the study were to analyze differences in surgical and oncological outcomes, as well as quality of life (QoL) and function in patients with ankle sarcomas undergoing three forms of surgical treatment, minor or major limb salvage surgery (LSS), or amputation. Methods A total of 69 patients with ankle sarcomas, treated between 1981 and 2017 at two tumour centres, were retrospectively reviewed (mean age at surgery: 46.3 years (SD 22.0); 31 females (45%)). Among these 69 patients 25 were analyzed prospectively (mean age at latest follow-up: 61.2 years (SD 20.7); 11 females (44%)), and assessed for mobility using the Prosthetic Limb Users Survey of Mobility (PLUS-M; for amputees only), the Toronto Extremity Salvage Score (TESS), and the University of California, Los Angeles (UCLA) Activity Score. Individual QoL was evaluated in these 25 patients using the five-level EuroQol five-dimension (EQ-5D-5L) and Fragebogen zur Lebenszufriedenheit/Questions on Life Satisfaction (FLZ). Results Of the total number of patients in the study, 22 (32%) underwent minor LSS and 22 (32%) underwent major LSS; 25 underwent primary amputation (36%). Complications developed in 26 (38%) patients, and were more common in those with major or minor LSS in comparison to amputation (59% vs 36% vs 20%; p = 0.022). A time-dependent trend towards higher complication risk following any LSS was present (relative risk: 0.204; 95% confidence interval (CI) 0.026 to 1.614; p = 0.095). In the prospective cohort, mean TESS was higher following minor LSS in comparison to amputation (91.0 vs 67.3; p = 0.006), while there was no statistically significant difference between major LSS and amputation (81.6 vs 67.3; p = 0.099). There was no difference in mean UCLA (p = 0.334) between the three groups (p = 0.334). None of the items in FLZ or EQ-5D-5L were different between the three groups (all p > 0.05), except for FLZ item “self-relation”, being lower in amputees. Conclusion Complications are common following LSS for ankle sarcomas. QoL is comparable between patients with LSS or amputation, despite better mobility scores for patients following minor LSS. We conclude that these results allow a decision for amputation to be made more easily in patients particularly where the principles of oncological surgery would otherwise be at risk. Cite this article: Bone Joint J 2021;103-B(3):553–561.

Percutaneous autologous impaction bone graft for advanced femoral head osteonecrosis: a retrospective observational study of unsatisfactory short-term outcomes

Background Half of osteonecrosis of the femoral head (ONFH) patients suffer femoral head collapse at initial diagnosis, and more than half are bilaterally affected. This study developed a percutaneous autologous impaction bone graft (IBG) technique as a modification of core decompression (CD). We also summarized the short-term results and treatment efficacy of percutaneous autologous IBG in advanced ONFH. Methods Twenty patients (12 males, 8 females) with nontraumatic, postcollapse ONFH except one case underwent CD (10-mm core diameter) and reverse IBG. Radiological changes of the ONFH stage and type were analyzed. Survival analysis using Kaplan–Meier estimates was performed with conversion to total hip arthroplasty (THA) as the endpoint. In addition, the Harris hip score (HHS) and University of California, Los Angeles (UCLA) activity rating scale were evaluated. Results Percutaneous autologous IBG was performed successfully, with an average operation time of < 1 h and small blood loss, and 7 patients (35%) needed conversion to THA at an average of 17 months postoperatively. We observed radiological progressive change in 60% of the patients during a mean observation period of 3 years. The mean clinical scores, except data recorded, after THA significantly improved (before vs. after 3 years: UCLA activity score, 3.7 vs. 5.2 [P = 0.014]; HHS, 57.6 vs. 76.5 points [P = 0.005]). In addition, 6 patients showed radiological progression but no clinical deterioration. Conclusions Percutaneous autologous IBG was technically simple and minimally invasive, but short-term results were unsatisfactory for advanced ONFH. Indications for this procedure should be carefully examined to improve it in order to enable bone formation.

Hydroxyapatite-Coated Compaction Short Stem Represents a Characteristic Pattern of Peri-Prosthetic Bone Remodelling After Total Hip Arthroplasty

Purpose: We aimed to investigate the differences in peri-prosthetic bone remodelling between the full hydroxyapatite (HA)-collared compaction short stem and the short tapered-wedge stem.Methods: This retrospective cohort study enrolled 159 consecutive patients (159 joints) undergoing total hip arthroplasty (THA) using the full HA compaction short (n=64) and short tapered-wedge (n=95) stems. Body mass index (BMI), peri-prosthetic bone mineral density (BMD), and clinical factors, including the Japanese Orthopaedic Association score and the University of California Los Angeles (UCLA) activity score, were assessed and compared.Results: Both groups showed similar peri-prosthetic BMD changes. Peri-prosthetic BMD was almost maintained in the distal femur and Gruen zone 6 with both type of stems, but significant BMD loss was found in zones 1 and 7 in both groups and in zone 2 of the full HA compaction stem group. Significant positive correlations were found between the proximal femoral BMD changes and the UCLA score in the tapered-wedge stem group but not between BMD changes and clinical factors in the full HA compaction stem group. Femoral bone shape affected the peri-prosthetic BMD changes in the tapered-wedge stem but not in the full HA compaction group. The stem collar of the full HA compaction stem did not affect peri-prosthetic BMD, but unique bone remodelling in the calcar region was observed in 27.6% cases.Conclusion: Peri-prosthetic bone remodelling remained unaffected by clinical and radiographic factors after THA with the new short full HA compaction stem. Therefore, the new stem may be useful in a variety of cases.

Effect of activity level after a posterior-stabilized TKA on the relative bone mineral density measured on standard radiographs in periprosthetic tibial bone

Background: The aim of this study was to evaluate the effect of activity level after a posterior-stabilized total knee arthroplasty (TKA) on the relative bone mineral density (rBMD) measured on standard radiographs in periprosthetic tibial bone. Methods: A retrospective review identified 110 patients (110 knees，20 men/90 women) who underwent PS TKA with 5 years follow-up. Patients activity level was evaluated by University of California Los Angeles (UCLA) activity score, and the rBMD in periprosthetic tibial bone was measured on anteroposterior X-ray images. Clinical assessments included Western Ontario and McMaster Universities (WOMAC), Knee Society score (KSS) and visual analogue scale (VAS). Nonlinear regression analysis was used to assess the impact of activity levels on periprosthesis bone density.Results: During 5-year follow-up period, the bone density in the medial, lateral and distal areas decreased compared with that before surgery (p<0.0001). There was a U-shaped distribution between UCLA activity rating and rBMD loss, with the lowest rBMD loss when the UCLA activity score was between 6-8 at 1 and 3 years. The curve fitting of UCLA activity level and rBMD% showed there was a parabolic relationship between UCLA activity level and rBMD% at 1 and 3 years after surgery (P<0.001, P=0.001), while there was no significant relationship between UCLA activity level and rBMD% at 5 years after surgery (P=0.436).Conclusions: We found that physical activity had a significant effect on radiographic measurements of BMD at 1 and 3 years but not at 5 years. Moderate activity may be associated with less proximal tibial BMD loss after TKA, therefore it may be the most appropriate activity intensity for patients with TKA.