Patient-related risk factors associated with less favourable outcomes following hip arthroscopy

Primary Hip Arthroscopy in Patients With Acetabular Dysplasia: A Systematic Review of Published Clinical Outcomes at Minimum 5-Year Follow-up

BACKGROUND

Hip arthroscopy in patients with borderline hip dysplasia has satisfactory outcomes at short-term follow-up; however, the data on midterm outcomes are inconsistent, and failure rates are high in some studies, limiting understanding of the role and utility of hip arthroscopy in this patient cohort.

PURPOSE

To provide an up-to-date, evidence-based review of the clinical outcomes of primary hip arthroscopy in patients with frank or borderline hip dysplasia at ≥5-year follow-up and report the failure rate and progression to total hip arthroplasty in this cohort.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A comprehensive literature search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they evaluated outcomes of primary hip arthroscopy in patients with lateral center-edge angle (LCEA) <25° at ≥5-year follow-up. Risk of bias assessment was performed using the methodological index for non-randomized studies scoring system. Level of evidence was determined using criteria from the Oxford Centre for Evidence-Based Medicine.

RESULTS

Nine studies were included in this review. Patients with LCEA <25° demonstrated satisfactory clinical outcomes, high patient satisfaction, and significant postoperative improvements in patient-reported outcomes (PROs) at follow-up ranging from a ≥5 to 10 years. Studies comparing patients with dysplasia to those without did not demonstrate significant differences in preoperative, postoperative, or delta PROs or in failure, reoperation, or revision rates. There was no overall significant correlation between outcomes and LCEA stratification.

CONCLUSION

Hip arthroscopy in carefully selected patients with LCEA <25° can be successful at mid- to long-term follow-up and may provide clinical outcomes and failure rates comparable with patients with normal LCEA, understanding that this is a singular, 2-dimensional radiographic measure that does not differentiate instability from impingement or combinations thereof, warranting future studies delineating these differences. These findings suggest that hip dysplasia may not be an absolute contraindication for isolated hip arthroscopy and may serve as a viable intervention with consideration of staged future periacetabular osteotomy (PAO). Importantly, this review does not suggest that hip arthroscopy alters the natural history of dysplasia; therefore, patients with dysplasia should be counseled on the potential utility of PAO by appropriate hip preservation specialists.

Clinical Equipoise in the Management of Patients With Femoroacetabular Impingement Syndrome and Concomitant Tönnis Grade 2 Hip Osteoarthritis or Greater: An International Expert-Panel Delphi Study

PURPOSE

To gather global-expert opinion on the management of patients with femoroacetabular impingement syndrome (FAIS) and Tönnis grade 2 hip osteoarthritis (OA) or greater.

METHODS

An internet-based modified Delphi methodology was used via an online platform (Online Surveys) using the CREDES (Conducting and Reporting Delphi Studies) guidelines. The expert panel comprised 27 members from 18 countries: 21 orthopaedic surgeons (78%), 5 physiotherapists (18%), and 1 dual orthopaedic surgeon-sport and exercise medicine physician (4%). Comments and suggestions were collected during each round, and amendments were performed for the subsequent round. Between each pair of rounds, the steering panel provided the experts with a summary of results and amendments. Consensus was set a priori as minimum agreement of 80%.

RESULTS

Complete participation (100%) was achieved in all 4 rounds. A final list of 10 consensus statements was formulated. The experts agreed that there is no single superior management strategy for FAIS with Tönnis grade 2 OA and that Tönnis grade 3 OA and the presence of bilateral cartilage defects (acetabular and femoral) is a contraindication for hip preservation surgery. Nonoperative management should include activity modification and physiotherapy with hip-specific strengthening, lumbo-pelvic mobility training, and core strengthening. There was no consensus on the need for 3-dimensional imaging for initial quantification of joint degeneration.

CONCLUSIONS

There is clinical equipoise in terms of the best management strategy for patients with FAIS and Tönnis grade 2 OA, and therefore, there is an urgent need to perform a randomized controlled trial for this cohort of patients to ascertian the best management strategy.

LEVEL OF EVIDENCE

Level V, expert opinion.

Secondary Hip Labral Reconstruction Yields Inferior Minimum 2-Year Functional Outcomes to Primary Reconstruction Despite Comparable Intraoperative Labral Characteristics

PURPOSE

To compare intraoperative labral characteristics and minimum 2-year functional outcomes of allograft labral reconstruction in primary versus revision hip arthroscopy across multiple orthopaedic centers.

METHODS

A retrospective multicenter hip arthroscopy registry was queried for patients with completed labral reconstruction surgeries from January 2014 to March 2023 with completed 2-year international Hip Outcome Tool-12 (iHOT-12) reports. Age, sex, and major intraoperative variables also were collected. Patients were placed in cohorts based on whether their arthroscopic allograft labral reconstruction was a primary procedure or secondary procedure (reconstruction following failed hip arthroscopy). One-way analysis of variance was performed on continuous variables. χ2 test was performed on categorical variables. Achievement of minimal clinically important difference (MCID), Patient Acceptable Symptom State (PASS), and Substantial Clinical Benefit (SCB) also was assessed.

RESULTS

In total, 77 patients met the inclusion and exclusion criteria and had complete information. The primary reconstruction group (n = 50) was significantly older than the secondary reconstruction group (n = 27) (47.5 ± 10.5 vs 39.1 ± 8.8 years; P = .001). In both cohorts, most patients had labral bruising, advanced labral degeneration, and/or grade III complexity of labral tearing. There was no difference in any recorded intraoperative findings (P = .160, P = .783, P = .357, respectively). Each cohort experienced significant improvement in iHOT-12 scores (P < .0001). However, patients undergoing secondary labral reconstruction reported inferior iHOT-12 scores (60.1 ± 29.2 vs 74.8 ± 27.0; P = .030). Patients undergoing primary reconstruction were more likely to reach MCID, PASS, and nearly normal SCB (92 vs 66.7%, P = .024; 68.0 vs 40.7%, P = .021; 76.0 vs 48.1%, P = .014, respectively).

CONCLUSIONS

Primary and secondary allograft labral reconstruction show clinical improvement, but primary reconstruction demonstrates better outcomes and greater percentage of patients reaching MCID, PASS, and nearly normal SCB than reconstruction in the revision setting.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic case-control study.

Editorial Commentary: Suboptimal Early Postsurgical Outcomes May Indicate Poor Long-Term Outcomes as a Result

Recent research has shown that hip arthroscopy outcomes at 6 months correlate with long-term outcomes. In theory, a score below a certain "threshold" at 6 months might predict poor long-term outcomes and thus allow intervention to improve the future prognosis of recovery and success. Yet, the trajectory toward a positive-or less than positive-outcome is dependent on multiple factors, and evaluation of patient-reported outcome measures in the early postoperative period may not reliably predict the long-term result.

Hip Arthroscopy in Patients With Generalized Joint Hypermobility Yields Successful Outcomes: A Systematic Review

PURPOSE

To evaluate the outcomes of hip arthroscopy in patients with generalized joint hypermobility (GJH).

METHODS

A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses. An electronic record search was performed in PubMed, Web of Science, Cochrane Library, and Embase. A 2-stage title/abstract and full-text screening was performed using the following inclusion criteria: (1) observational studies, cohort studies, and randomized controlled trials; (2) describing more than 5 patients with a mean age over 18 years and GJH; (3) undergoing arthroscopy of the hip; (4) reporting patient-reported outcome measures (PROMs), return to sport, or complications/reoperations; and (5) published in English.

RESULTS

Of the 517 articles identified, 10 studies meeting all selection criteria were included. Included studies report significant improvements in a range of different functional and pain-based PROMs. Most patients (25.0%-97.0%) in each study achieved a clinically important improvement postoperatively in at least 1 PROM. No complications were described in any of the 4 studies reporting this metric. One study each found an association between GJH and an increased risk of postoperative deep gluteal syndrome and iliopsoas tendinitis. The rate of revision arthroscopy ranged from 0% to 11.4%, and only 2 patients in a single study of 11 hips required conversion to total hip arthroplasty. No statistically significant differences were reported between patients with and without GJH with respect to any of the described outcomes.

CONCLUSIONS

Patients with GJH may achieve good outcomes following hip arthroscopy with respect to PROMs, perioperative complications, reoperation, and return to sport. With effective labral repair and capsular closure, outcomes achieved in patients with GJH are comparable to those reported in patients without hypermobility.

LEVEL OF EVIDENCE

Level IV, systematic review of level III to IV studies.

Concomitant Ipsilateral Knee Pain Is Associated With Worse Preoperative Functional Status and Short-Term Outcomes After Hip Arthroscopy in Patients With Femoroacetabular Impingement Syndrome

PURPOSE

(1) To determine the effect of concomitant ipsilateral knee pain (IKP) on short-term outcomes after hip arthroscopic treatment of femoroacetabular impingement syndrome (FAIS) and (2) to determine whether IKP would improve with surgery.

METHODS

Data between September 2021 and May 2022 were reviewed. Patients with a diagnosis of FAIS who underwent hip arthroscopy with a minimum of 1-year follow-up were included. The exclusion criteria were prior ipsilateral hip or knee surgery, hip Tönnis grade greater than 1, knee Kellgren-Lawrence grade greater than 2, hip conditions (avascular necrosis, Legg-Calvé-Perthes disease, pigmented villonodular synovitis, osteoid osteoma, synovial chondromatosis, and developmental dysplasia of the hip), and spine diseases. All patients underwent knee magnetic resonance imaging preoperatively. Preoperative and short-term (1-year) patient-reported outcomes were collected, consisting of the Hip Sports Activity Scale score, weekly sports participation, modified Harris Hip Score (mHHS), 12-component International Hip Outcome Tool (iHOT-12) score, and visual analog pain scale (VAS) scores for the hip and the ipsilateral knee. The percentages of patients achieving the minimal clinically important difference and patient acceptable symptom state (PASS) for the mHHS and iHOT-12 score were calculated. Multivariate regression analysis was performed to determine the effect of IKP severity on postoperative outcomes. Subgroup analysis was performed between patients with IKP alleviation and those without IKP alleviation.

RESULTS

Among the 107 patients included, 47 presented with preoperative IKP. Compared with patients without IKP, the IKP cohort had comparable knee structural abnormalities (all with P > .05). Still, the IKP cohort showed inferior preoperative values for the mHHS (P = .003), iHOT-12 score (P = .016), hip VAS score (P = .001), and weekly sports participation (P = .039). Postoperatively, the IKP cohort had a lower mHHS (P = .046), lower iHOT-12 score (P = .037), and lower hip VAS score (P = .003) and were less likely to achieve the PASS for the mHHS (P = .021) and iHOT-12 score (P = .049). Patients with higher knee VAS scores were less likely to achieve the PASS for the mHHS (odds ratio, 0.61; P = .023). Within the IKP group, the knee VAS score improved from 2.3 to 1.0 (P < .001). Patients with alleviated IKP showed superior postoperative iHOT-12 scores (P = .038) compared with patients with persistent IKP.

CONCLUSIONS

Concomitant IKP at baseline negatively affected preoperative status and short-term clinical outcomes after arthroscopic treatment of FAIS. Patients with IKP were less likely to meet clinical thresholds. Most patients achieved IKP alleviation postoperatively, which was associated with superior clinical outcomes.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

PREHAB FAI- Prehabilitation for patients undergoing arthroscopic hip surgery for Femoroacetabular Impingement Syndrome -Protocol for an assessor blinded randomised controlled feasibility study

BACKGROUND

The past decade has seen an exponential growth of minimally invasive surgical procedures. Procedures such as hip arthroscopy have rapidly grown and become the standard of care for patients with Femoroacetabular Impingement Syndrome (FAIS). Although, the results of such procedures are encouraging, a large proportion of patients do not achieve optimal outcomes due to chronicity and deconditioning as a result of delay in diagnosis and increased waiting times amongst other factors. In a recent systematic review and meta-analysis of randomised control trials, moderate certainty evidence supported prehabilitation over standard care in optimising several domains including muscle strength, pain and health related quality of life in patients undergoing orthopaedic surgical interventions. However, the role of prehabilitation in patients with FAI syndrome undergoing hip arthroscopy has received little attention.

AIM

To evaluate the feasibility, suitability, acceptability and safety of a prehabilitation programme for FAI to inform a future definitive randomised control trial to assess effectiveness.

METHODS

A systematically developed prehabilitation intervention based on a literature review and international consensus will be utilised in this study. A mixed methodology encompassing a two-arm randomised parallel study alongside an embedded qualitative component will be used to answer the study objectives. Patients will be recruited from a tertiary referral NHS centre for young adult hip pathology in the UK. Patient reported outcomes such as iHOT-12, Brief Pain Inventory Scale (Short form), Hospital Anxiety and Depression Scale and Patient Global Impression of Change score will be obtained alongside objective measurements such as Muscle Strength and Star Excursion Balance Test at various time points. Outcome measures will be obtained at baseline (prior to prehabilitation intervention), after prehabilitation before surgery, and at 6 weeks+/- 4 weeks and 6 months +/- 4 weeks (planned primary endpoint for definitive RCT) postoperatively when participants attend the research site for clinical care and remotely at 12 months +/- 4 weeks postoperatively. Mean change and 95% CI, and effect size of outcome measures will be used to determine the sample size for a future RCT. For the qualitative component, in depth face-to-face semi-structured interviews with physiotherapists and focus groups with participants will be conducted to assess the feasibility, suitability, and acceptability of the prehabilitation intervention using a predetermined success criteria. All qualitative data will be recorded, transcribed verbatim and thematically analysed.

DISCUSSION

This study will be first of its kind to evaluate a systematically developed prehabilitation intervention for patients with FAIS undergoing hip arthroscopy. This study will provide important preliminary data to inform feasibility of a definitive RCT in the future to evaluate effectiveness of a prehabilitation intervention.

TRIAL REGISTRATION

ISRCTN 15371248, 09/03/2023.

TRIAL PROTOCOL

Version 2.3, 26th June 2023.

Development of Machine-Learning Algorithms to Predict Attainment of Minimal Clinically Important Difference After Hip Arthroscopy for Femoroacetabular Impingement Yield Fair Performance and Limited Clinical Utility

PURPOSE

To determine whether machine learning (ML) techniques developed using registry data could predict which patients will achieve minimum clinically important difference (MCID) on the International Hip Outcome Tool 12 (iHOT-12) patient-reported outcome measures (PROMs) after arthroscopic management of femoroacetabular impingement syndrome (FAIS). And secondly to determine which preoperative factors contribute to the predictive power of these models.

METHODS

A retrospective cohort of patients was selected from the UK's Non-Arthroplasty Hip Registry. Inclusion criteria were a diagnosis of FAIS, management via an arthroscopic procedure, and a minimum follow-up of 6 months after index surgery from August 2012 to June 2021. Exclusion criteria were for non-arthroscopic procedures and patients without FAIS. ML models were developed to predict MCID attainment. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC).

RESULTS

In total, 1,917 patients were included. The random forest, logistic regression, neural network, support vector machine, and gradient boosting models had AUROC 0.75 (0.68-0.81), 0.69 (0.63-0.76), 0.69 (0.63-0.76), 0.70 (0.64-0.77), and 0.70 (0.64-0.77), respectively. Demographic factors and disease features did not confer a high predictive performance. Baseline PROM scores alone provided comparable predictive performance to the whole dataset models. Both EuroQoL 5-Dimension 5-Level and iHOT-12 baseline scores and iHOT-12 baseline scores alone provided AUROC of 0.74 (0.68-0.80) and 0.72 (0.65-0.78), respectively, with random forest models.

CONCLUSIONS

ML models were able to predict with fair accuracy attainment of MCID on the iHOT-12 at 6-month postoperative assessment. The most successful models used all patient variables, all baseline PROMs, and baseline iHOT-12 responses. These models are not sufficiently accurate to warrant routine use in the clinic currently.

LEVEL OF EVIDENCE

Level III, retrospective cohort design; prognostic study.

The impact of pre-operative mental health on outcomes of foot and ankle surgery: A scoping review

BACKGROUND

Evidence suggests that certain groups of orthopaedic patients have an increased prevalence of mental health disorders than the general population. This scoping review aims to evaluate the effect of pre-operative mental health on outcomes of foot and ankle surgery.

METHODS

A literature search was performed in four databases. Studies investigating a relationship between preoperative mental health and postoperative patient reported outcome measures (PROMs), complications, readmissions or reoperations were included.

RESULTS

Of the 19 studies investigating the effect of preoperative mental health on PROMs, 16 (84.2%) reported a significant relationship between poorer preoperative mental health and inferior postoperative PROMs. Poorer mental health was associated with an increased rate of complications, readmissions and/or reoperations in four studies.

CONCLUSIONS

Poorer preoperative mental health is associated with significantly inferior outcomes following foot and ankle surgery. Clinicians should evaluate mental health to stratify likely outcomes and aid in the management of patient expectations.

LEVEL OF EVIDENCE

Level IV: Scoping review of Level II-IV studies.

Predicting Outcomes in Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE OF REVIEW

Arthroscopic treatment of femoroacetabular impingement syndrome (FAIS) continues to rise in incidence, and thus there is an increased focus on factors that predict patient outcomes. The factors that impact the outcomes of arthroscopic FAIS treatment are complex. The purpose of this review is to outline the current literature concerning predictors of patient outcomes for arthroscopic treatment of FAIS.

RECENT FINDINGS

Multiple studies have shown that various patient demographics, joint parameters, and surgical techniques are all correlated with postoperative outcomes after arthroscopic FAIS surgery, as measured by both validated patient-reported outcome (PRO) scores and rates of revision surgery including hip arthroplasty. To accurately predict patient outcomes for arthroscopic FAIS surgery, consideration should be directed toward preoperative patient-specific factors and intraoperative technical factors. The future of accurately selecting patient predictors for outcomes will only improve with increased data, improved techniques, and technological advancement.

Physical Therapy May Not Be Successful for Patients With Cam-Type Femoroacetabular Impingement Syndrome and May Result in Insufficient Hip Range of Motion When Femoral Anteversion Is Less Than 16° and α-Angle Is Greater Than 65°

PURPOSE

To identify factors associated with insufficient range of motion (ROM) improvement after the posterior pelvic tilt change in cam-type femoroacetabular impingement syndrome.

METHODS

Preoperative computed tomography images from 71 consecutive patients with femoroacetabular impingement syndrome treated with arthroscopic cam resection were evaluated. Using a dynamic computer simulation program, 3-dimensional models with a 10° posterior pelvic tilt from the supine functional pelvic plane (baseline) were created by computed tomography models. Patients were divided into 2 groups: those who experienced >10° (effective group) and ≤10° (ineffective group) improvements in internal rotation at 90° flexion after a 10° posterior pelvic tilt. Demographic characteristics; preoperative range of internal rotation at 90° flexion; and radiographic parameters, including Tönnis grade, lateral center-edge angle, acetabular roof obliquity angle, central acetabular anteversion, cranial acetabular anteversion, femoral anteversion, and α angle, were compared in the 2 groups. Univariate and multivariable logistic regression analyses were performed to evaluate factors associated with insufficient ROM improvement following a 10° posterior pelvic tilt.

RESULTS

The 71 patients included 58 men and 13 women, of mean age 41.4 ± 14.6 years. Posterior pelvic tilt was effective in 13 hips and ineffective in 58. Univariate analysis showed that preoperative range of internal rotation at 90°flexion, femoral anteversion, and α angle differed significantly in the 2 groups. Multivariable analysis showed that femoral anteversion <16° (odds ratio 7.4; 95% confidence interval 1.6-35; P = .012) and α angle >65° (odds ratio 6.7; 95% confidence interval 1.2-37; P = .027) were significant factors associated with insufficient ROM improvement after posterior pelvic tilt.

CONCLUSIONS

Physical therapy may not be successful for patients with cam-type femoroacetabular impingement syndrome and may result in insufficient hip ROM when femoral anteversion is less than 16° and α-angle is greater than 65°.

CLINICAL RELEVANCE

Patients with a prominent cam-type deformity and lower anterior femoral anteversion are at high risk of clinical failure following improvement in pelvic mobility by conservative treatment alone and are likely to benefit from surgery for cam deformity.

Functional Outcome Scores and Conversion to Total Hip Arthroplasty After Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Patients With Tönnis Grade 1 Versus Grade 0 Arthritis: A Propensity-Matched Study at Minimum 10-Year Follow-up

BACKGROUND

Hip arthroscopy has become the mainstay surgical intervention for the treatment of femoroacetabular impingement syndrome (FAIS). However, postoperative outcomes and rates of secondary surgery are mixed in patients with differing levels of preoperative osteoarthritis (OA). Furthermore, there is a paucity of literature comparing patients with and without OA at long-term follow-up.

PURPOSE

To compare outcomes and rates of secondary surgery at minimum 10-year follow-up, including revision hip arthroscopy and conversion to total hip arthroplasty (THA), in patients with Tönnis grade 1 undergoing hip arthroscopy for FAIS compared with a propensity-matched control group of patients with Tönnis grade 0.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent primary hip arthroscopy for FAIS between January 2012 and February 2013 were identified. Patients with Tönnis grade 1 were propensity matched in a 1:2 ratio by age, sex, and body mass index (BMI) to patients with Tönnis grade 0. Patient-reported outcomes (PROs) were collected at varying timepoints including preoperatively and 1, 2, 5, and 10 years postoperatively and compared between the 2 cohorts. Rates of minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) achievement at 10 years were evaluated and compared between groups. Rates of secondary surgery including revision hip arthroscopy and conversion to total hip arthroplasty (THA) were evaluated. Gross survivorship between cohorts was evaluated using a Kaplan-Meier gross survivorship curve. A subanalysis was performed comparing patients with Tönnis grade 1 who converted to THA and those who did not.

RESULTS

A total of 31 patients with Tönnis grade 1 (age, 42.6 ± 9.0 years; BMI, 28.0 ± 6.3) were successfully matched to 62 patients with Tönnis grade 0 (age, 42.1 ± 8.5, P = .805; BMI, 26.1 ± 3.9, P = .117). Both the Tönnis grade 1 and Tönnis grade 0 groups demonstrated significant improvements regarding all PROs at minimum 10 years (P < .05 for all), except for the Hip Outcome Score Activities of Daily Living subscale (HOS-ADL) (P = .066) in the Tönnis grade 1 cohort. No significant difference (P > .05 for all) was noted between cohorts regarding any 10-year PRO. When the authors evaluated comparisons between preoperative and 1-, 2-, 5-, and 10-year PRO measures, significant differences were noted between cohorts regarding 2-year HOS-ADL (P = .021), Hip Outcome Score Sports-Specific subscale (P = .016), and modified Harris Hip Score (P = .026); otherwise, differences did not reach significance. High rates of 10-year MCID and PASS achievement were seen, with no significant differences between groups. Patients with Tönnis grade 1 had significantly higher rates of conversion to THA compared with patients who had Tönnis grade 0 (25.8% vs 4.8%; P = .006). Patients with Tönnis grade 1 had significantly lower gross survivorship compared with those who had Tönnis grade 0 (71.0% vs 85.5%, respectively; P = .04).

CONCLUSION

Hip arthroscopy confers comparable postoperative clinical improvements to patients who have FAIS with and without mild OA; however, the benefits among patients with mild OA may be less durable. Patients with Tönnis grade 1 had significantly higher conversion to THA and reduced gross survivorship compared with patients with no evidence of preoperative OA, suggesting that patients with evidence of OA may need to be cautioned on the higher rate of conversion surgery.

Workers' Compensation Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement Syndrome Experience Worse Mid-Term Outcomes but Similar Return-to-Work: A Propensity-Matched Analysis at 5-Year Follow-Up

PURPOSE

To investigate mid-term patient-reported outcomes (PROs) and return-to-work for workers' compensation (WC) patients undergoing primary hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) versus propensity-matched, non-WC controls and to determine whether achievement rates of minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) differ between these populations.

METHODS

A retrospective cohort study was conducted on WC patients who underwent primary HA for FAIS from 2012 to 2017. WC and non-WC patients were propensity matched on a 1:4 basis by sex, age, and body mass index (BMI). PROs were compared preoperatively and at 5 years postoperatively, employing the Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales, modified Harris Hip Score (mHHS), 12-item international Hip Outcome Tool (iHOT-12), and visual analog scales (VAS) for pain and satisfaction. MCID and PASS were calculated using published thresholds for these measures. Preoperative and postoperative radiographs and the presence and timing of return to unrestricted work were evaluated.

RESULTS

Forty-three WC patients were successfully matched to 172 non-WC controls and followed for 64.2 ± 7.7 months. WC patients demonstrated lower preoperative scores for all measures (P ≤ .031) and worse HOS-ADL, HOS-SS, and VAS pain scores at 5-year follow-up (P ≤ .021). There were no differences in MCID achievement rates or magnitude of change between preoperative and 5-year postoperative PROs (P ≥ .093); however, WC patients achieved PASS at lower rates for HOS-ADL and HOS-SS (P ≤ .009). 76.7% of WC and 84.3% of non-WC patients returned to work without restrictions (P = .302) at 7.4 ± 4.4 versus 5.0 ± 3.8 months, respectively (P < .001).

CONCLUSIONS

WC patients undergoing HA for FAIS report worse preoperative pain and function than non-WC patients and experience worse pain, function, and PASS achievement at 5-year follow-up. However, they demonstrate similar MCID achievement and magnitude improvement between preoperative and 5-year postoperative PROs, and return to work without restrictions at a similar rate to non-WC patients, although they may take longer to do so.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Does response to preoperative intra-articular anesthetic injections predict outcomes of femoroacetabular impingement syndrome?

INTRODUCTION

Some patients with femoroacetabular impingement syndrome (FAIS) who undergo surgery do not show satisfactory outcomes. Reliable tests that can inform prognosis of FAIS surgery are needed for optimized indications and contraindications to surgery. We aimed to review and critically appraise available literature on the capability of patient response to preoperative intra-articular anesthetic injections (PIAI) to predict post-surgical outcomes in patients with FAIS.

MATERIALS AND METHODS

This study was conducted in accordance with the PRISMA statement. Studies that assessed the patient pain response to PIAI and post-surgical outcomes in patients with FAIS were considered eligible. Study selection and data collection were performed by three independent reviewers. Main outcomes evaluated were those measured by hip outcome scales often used in assessing postoperative pain and functional recovery, such as the modified Harris Hip Score (mHHS) and international Hip Outcome Tool (iHOT). The likelihood ratio of achieving satisfactory postoperative outcomes at the mHHS (LHR) was extracted or calculated-for patients with significant response to PIAI and for those without a significant response to PIAI. The risk of bias was assessed using the Quality In Prognosis Studies (QUIPS) tool.

RESULTS

Six studies were considered eligible for analysis. Five studies indicated that patient response to PIAI are associated to surgical outcomes for patients with FAIS, with a greater reduction in pain typically indicating a better surgical outcome. Additionally, the LHR ranged from 1.15 to 1.92 for patients with significant response to PIAI (I2 = 90.6%). For patients without a significant response, the LHR ranged from 0.18 to 0.65 (I2 = 87.5). An overall high risk of bias was observed for all studies included in the analysis. Study attrition, the prognostic factor measurement and the presence of confounding factors were the main sources of bias.

CONCLUSIONS

Greater reductions in pain with preoperative intra-articular anesthetic injections were found to be associated to better outcomes after FAIS surgery, but all available studies contain a high risk of bias.

Stratified care in hip arthroscopy: can we predict successful and unsuccessful outcomes? Development and external temporal validation of multivariable prediction models

OBJECTIVE

Although hip arthroscopy is a widely adopted treatment option for hip-related pain, it is unknown whether preoperative clinical information can be used to assist surgical decision-making to avoid offering surgery to patients with limited potential for a successful outcome. We aimed to develop and validate clinical prediction models to identify patients more likely to have an unsuccessful or successful outcome 1 year post hip arthroscopy based on the patient acceptable symptom state.

METHODS

Patient records were extracted from the Danish Hip Arthroscopy Registry (DHAR). A priori, 26 common clinical variables from DHAR were selected as prognostic factors, including demographics, radiographic parameters of hip morphology and self-reported measures. We used 1082 hip arthroscopy patients (surgery performed 25 April 2012 to 4 October 2017) to develop the clinical prediction models based on logistic regression analyses. The development models were internally validated using bootstrapping and shrinkage before temporal external validation was performed using 464 hip arthroscopy patients (surgery performed 5 October 2017 to 13 May 2019).

RESULTS

The prediction model for unsuccessful outcomes showed best and acceptable predictive performance on the external validation dataset for all multiple imputations (Nagelkerke R2 range: 0.25-0.26) and calibration (intercept range: -0.10 to -0.11; slope range: 1.06-1.09), and acceptable discrimination (area under the curve range: 0.76-0.77). The prediction model for successful outcomes did not calibrate well, while also showing poor discrimination.

CONCLUSION

Common clinical variables including demographics, radiographic parameters of hip morphology and self-reported measures were able to predict the probability of having an unsuccessful outcome 1 year after hip arthroscopy, while the model for successful outcome showed unacceptable accuracy. The externally validated prediction model can be used to support clinical evaluation and shared decision making by informing the orthopaedic surgeon and patient about the risk of an unsuccessful outcome, and thus when surgery may not be appropriate.

Three-Dimensional CT and 3D MRI of Hip- Important Aids to Hip Preservation Surgery

Common hip internal derangements include femoroacetabular impingement (FAI), developmental dysplasia of hip (DDH) dysplasia, and avascular necrosis (AVN) of the femoral head. These are initially screened by radiographs. For preoperative planning of hip preservation, 3-dimensional (3D) CT is commonly performed to assess bony anatomy and its alterations. Magnetic resonance imaging (MRI) is used to evaluate labrum, hyaline cartilage, tendons, synovium, and loose bodies, and provides vital information for surgical decision-making. However, conventional 2D MRI techniques are limited by lack of isotropic multiplanar reconstructions and partial volume artifacts. With advancements in hardware and software, novel isotropic 3D MR Proton Density images are acquired with acceptable acquisition times leading to improved visualization of soft tissue and osseous structures for various hip conditions. Three-Dimensional MRI allows multiplanar non-gap reconstructions along the structures of interest. It results in detection of small, otherwise inconspicuous labral tears without the need for MR arthrogram, which can be subsequently measured. In addition, radial reconstructions of the femoral head can be performed from original 3D volume MR imaging and CT imaging without the need for individual different plane acquisitions. Three-Dimensional MRI thus impacts surgical decision-making for the important common hip derangement conditions. For example, femoral head hyaline cartilage loss may make hip preservation difficult or impossible. In this review, we discuss the advantages and technical details of 3D CT and MRI and their significant role in aiding hip preservation surgery for common hip conditions. The conditions discussed in this article include FAI, DDH, AVN, synovial disorders, cartilaginous tumors, and hip fractures.

When are patients with osteoarthritis referred for surgery?

Current treatment strategies in hip and knee osteoarthritis (OA) involve a combined approach that includes not only modification of risk factors and conservative treatment but also joint-preserving surgical therapy in the early stages, or joint replacement in late OA. With the recent development of new etiological concepts (i.e. hip dysplasia and femoroacetabular impingement as major risk factors for hip OA), treatment alternatives for joint preservation could be extended significantly. Satisfactory results of osteotomies and other reconstructive procedures around hip and knee joints can only be expected in early OA (Kellgren/Lawrence grade 0-II). If patients with advanced radiographic OA grades III-IV do not respond to conservative treatment over at least 3 months and express a relevant burden of disease, joint replacement might be considered. Prior to surgery, potential contraindications must be excluded, patient expectations need to be discussed, and modifiable risk factors, which may negatively influence the outcome, should be optimized.

The HAR-index: a reliable method for evaluating the risk of total hip arthroplasty conversion after hip arthroscopy for femoroacetabular impingement

PURPOSE

Hip arthroscopy is a growing technique in the treatment of femoroacetabular impingement (FAI), but can sometimes lead to unsatisfactory results such as the early conversion to total hip arthroplasty (THA). The purpose of this study is to describe a new tool for assessing the preoperative risk of THA conversion after hip arthroscopy in patients with FAI.

METHODS

This study is a retrospective analysis of a prospective cohort of 584 patients with FAI who underwent hip arthroscopy at a single centre with a minimum 2 years follow-up. The preoperative variables of these patients were analysed to calculate the risk of each variable for THA. By selecting variables with an area under the receiver operating characteristic (ROC) curve greater than 0.7, a calculator was created to provide a risk index for each patient.

RESULTS

Four variables (age, body mass index, Tönnis score and ALAD) were associated with an increased risk of THA conversion. The optimal cut-off points for each variable were determined, and a risk index was created. The Hip-Arthroplasty-Risk Index (HAR-Index) is a 0-4 points scale obtained from four binary scores of 0 or 1 depending on whether the cut-off point for each variable was reached or not. The increased risk of THA for each HAR-Index value was 1.1%, 6.2%, 17.9%, 55.1% and 79.3% respectively. The HAR-Index showed a very good predictive capacity with an area under the ROC curve of 0.89.

CONCLUSION

The HAR-Index is a simple and practical tool for practitioners to make more informed decisions about performing hip arthroscopy in patients with FAI. With a very good predictive capacity, the HAR-Index can help to reduce the rate of conversion to THA.

LEVEL OF EVIDENCE

Level III.

High Survivorship and Comparable Patient-Reported Outcomes at a Minimum 5 Years After Hip Arthroscopic Surgery in Patients With Femoroacetabular Impingement, With and Without Lateral Rim Dysplasia

BACKGROUND

Femoroacetabular impingement (FAI) in patients with dysplasia presents a unique challenge to surgeons. Short-term outcomes are conflicting, while longer term follow-up data are only emerging.

PURPOSE

To quantify midterm (minimum 5-year follow-up) outcomes after the arthroscopic correction of FAI in the presence of lateral rim dysplasia compared with a matched control group with FAI with normal acetabular coverage.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Prospective outcome data, collected in a consecutive series of patients undergoing arthroscopic FAI correction with lateral rim dysplasia (lateral center-edge angle [LCEA] of 13°-25°), were reviewed (N = 75 cases). An age- and sex-matched control group of 120 cases was also formed (LCEA >25°). Survivorship was defined as the avoidance of total hip replacement and assessed using a Kaplan-Meier curve with the log-rank test. Survival rates and patient-reported outcome measure (PROM) scores (modified Harris Hip Score [mHHS], University of California, Los Angeles [UCLA], 36-Item Short Form Health Survey [SF-36], and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] preoperatively and at 5 years postoperatively) were compared between the groups. The proportion of patients across groups achieving the minimal clinically important difference (MCID) was compared for each PROM. The dysplasia group was also analyzed independently to identify any factors that may indicate a less favorable outcome using regression analysis. The group was divided into 2 subgroups: borderline dysplasia (LCEA of 20°-25°) and severe dysplasia (LCEA <20°).

RESULTS

The survival rate in the dysplasia group was 97%. There was no statistical difference with respect to survival rates or any PROM scores (P > .05 for all) between the groups. There were similar rates of achieving the MCID between the groups for the mHHS, UCLA, and WOMAC. The FAI control group had a higher rate of achieving the MCID for the SF-36 (P = .012; effect size = 0.274 [small]). Subgroup analysis indicated a lower survival rate (78% vs 100%, respectively; P < .001) in female cases in the dysplasia group (n = 9) compared with male cases in the dysplasia group (n = 66). The UCLA score in female cases in the dysplasia group at 5 years was statistically lower compared with that in male cases in the dysplasia group (6 vs 10, respectively; P = .003; effect size = 0.378 [medium]), but no other outcome revealed any differences between the sexes. There were also no variables identified on regression analysis that accurately predicted a poorer outcome in the dysplasia group. When stratified by severity, there was no difference in survivorship or outcomes between those with severe dysplasia (LCEA <20°; n = 11) and those with borderline dysplasia (LCEA of 20°-25°; n = 64).

CONCLUSION

An arthroscopic intervention was a successful treatment option for FAI in the presence of lateral rim dysplasia at midterm follow-up. Irrespective of the severity of dysplasia, patients can expect similar improvements to those in patients with normal femoral head coverage.

Associating Outcomes After Hip Arthroscopy With Patient Resilience

Background

Higher patient resilience has been shown to be associated with improved patient-reported outcome measures (PROMs) at 6 months after hip arthroscopy.

Purpose

To examine the relationship between patient resilience and PROMs at minimum 2 years after hip arthroscopy.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were 89 patients (mean age, 36.9 years; mean follow-up, 4.6 years). Patient demographics, surgical details, and preoperative International Hip Outcome Tool-12 (iHOT-12) and visual analog scale (VAS) pain scores were collected retrospectively. Postoperative variables were collected via a survey and included the Brief Resilience Scale (BRS), Patient Activation Measure-13 (PAM-13), Pain Self-efficacy Questionnaire-2 (PSEQ-2), VAS satisfaction, and postoperative iHOT-12, and VAS pain scores. Based on the number of standard deviations from the mean BRS score, patients were stratified as having low resilience (LR; n = 18), normal resilience (NR; n = 48), and high resilience (HR; n = 23). Differences in PROMs were compared between the groups, and a multivariate regression analysis was performed to assess the relationship between pre- to postoperative change (Δ) in PROMs and patient resilience.

Results

There were significantly more smokers in the LR group compared with the NR and HR groups (P = .033). Compared with the NR and HR groups, patients in the LR group had significantly more labral repairs (P = .006), significantly worse postoperative iHOT-12, VAS pain, VAS satisfaction, PAM-13, and PSEQ-2 scores (P < .001 for all), and significantly lower ΔVAS pain and ΔiHOT-12 scores (P = .01 and .032, respectively). Regression analysis showed significant associations between ΔVAS pain and NR (β = -22.50 [95% CI, -38.81 to -6.19]; P = .008) as well as HR (β = -28.31 [95% CI, -46.96 to -9.67; P = .004) and between ΔiHOT-12 and NR (β = 18.94 [95% CI, 6.33 to 31.55]; P = .004) as well as HR (β = 20.63 [95% CI, 6.21 to 35.05]; P = .006). Male sex was a significant predictor of ΔiHOT-12 (β = -15.05 [95% CI, -25.42 to -4.69]; P = .006).

Conclusion

The study results indicate that lower postoperative resilience scores were associated with significantly worse PROM scores, including pain and satisfaction, at 2 years after hip arthroscopy.

Hip Arthroscopy in the Presence of Advanced Osteoarthritis Results in 57% Survivorship, With 78% Survivor Satisfaction, at 10 Years. A Matched-Control Study

PURPOSE

To (1) determine the 10-year survivorship (avoidance of total hip arthroplasty, THA) for patients with advanced osteoarthritis (OA) undergoing hip arthroscopy for femoroacetabular impingement, and (2) compare survivorship and patient-reported outcomes (PROs) with a matched-control group without OA.

METHODS

Advanced OA hips (Tönnis ≥2) were matched in a 1:1 ratio (age ± 5 years, sex) to hips with preoperative Tönnis grade ≤1. Exclusion criteria was dysplasia, age <18 years, previous hip conditions/surgeries, and bilaterally operated patients with OA on one side only. Survival was estimated by Kaplan-Meier analysis for levels of sex, age groups and Tönnis. Cox proportional hazards model estimated hazard ratios (HR) of undergoing THA conversion. Where THA was avoided, outcomes and proportion of cases achieving patient acceptable symptomatic state was determined RESULTS: 53 OA hips were matched with 53 control hips. Survival distributions were significantly different for: (1) Group: OA 57.1%, control 87.0% (P = .001); (2) Tönnis grade: Tönnis 0, 89.2%; Tönnis 1, 77.8%; Tönnis 2, 67.6%; Tönnis 3, 25.0% (P < .001); and (3) age: (OA: 75.0% vs 44.8%, control: 100%, vs 75.0%, for <35 and >35 years respectively) (P = .002). Conversion to THA was greater for increasing Tönnis: HR 1.9 (P = .450), 3.5 (P = .032), and 11.0 (P < .001) for Tönnis 1, 2, and 3 respectively, relative to no OA (Tönnis 0) and >35 years: HR 4.3 (95% confidence interval 1.6-11.3, P = .003). Patient acceptable symptomatic state achievement was similar for both groups (78% OA vs 91% control, P = .167). modified Harris Hip Score and Short Form-36 significantly improved within both groups from baseline to 10 years CONCLUSIONS: Arthroscopic correction of femoroacetabular impingement, in the presence of advanced OA results in 57% survivorship at 10 years (68% Tönnis 2, 25% Tönnis 3). Where THA was avoided, 78% considered their 10-year post-HA state to be satisfactory, with patient-reported outcomes similar to a matched non-OA cohort. Tönnis 2 in particular should be considered for arthroscopic hip preservation to avoid the need to prematurely replace the hip joint.

LEVEL OF EVIDENCE

IV, case series.

Lateral to Medial Joint Space Ratio is Predictive of Survivorship After Primary Hip Arthroscopy

PURPOSE

To assess whether preoperative joint space measures would be predictive of survivorship in patients undergoing hip arthroscopy (HA) for femoroacetabular impingement (FAI).

METHODS

Data on consecutive patients who underwent hip arthroscopy between February 2008 and February 2018 were retrospectively reviewed. To be eligible for final analysis, patients were required to have preoperative radiographs for joint space measurements and data indicating conversion to a total hip arthroplasty (THA), hip resurfacing, or neither; at a minimum of 2 years after primary hip arthroscopy. Survivorship following HA was defined as remaining conversion free and served as the primary outcome. A multivariate logistic regression analysis and receiver operator curve (ROC) were used to evaluate the correlation between joint space measurements and survivorship following HA.

RESULTS

A total of 1,885 primary arthroscopy cases were included in this study. The multivariate regression analysis found preoperative lateral-to-medial joint space ratio (L/M ratio) to be the strongest predictive factor of survivorship after primary hip arthroscopy (OR = 2.084, CI_95% = 1.239-3.503; P = .006). The ROC curve for the model demonstrated acceptable discrimination with an area under the curve (AUC) of 0.792. Patients with an L/M ratio ≥0.75 had a survivorship rate of 91.7% compared to a rate of 75% for patients with an L/M ratio <0.75 (OR: 3.68).

CONCLUSIONS

This study found that, of the factors evaluated in this study, the most significant factor in predicting survivorship at 2 years after undergoing primary hip arthroscopy was a larger lateral-to-medial joint space ratio. This may suggest an initiation of primary arthritis at the edge-loading area of the lateral acetabulum. LEVEL OF EVIDENCE: III, retrospective comparative observation study.

Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial

BACKGROUND

Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life.

PURPOSE

To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change.

RESULTS

A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (β = -0.82; P = .034), access to private health care (β = 12.91; P = .013), and worse baseline iHOT-33 score (β = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (β = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively).

CONCLUSION

No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.

No evidence exists on outcomes of non-operative management in patients with femoroacetabular impingement and concomitant Tönnis Grade 2 or more hip osteoarthritis: a scoping review

PURPOSE

The purpose of this scoping review was to assess the outcomes of all the non-operative modalities of management for femoroacetabular impingement (FAI) and concomitant osteoarthritis (OA) Tönnis Grade 2 or more.

METHODS

A systematic search of PubMed was performed from inception to December 1st 2021 for literature on outcomes of non-operative management strategies for young adults with symptomatic FAI using the PRISMA Extension for Scoping Reviews guidelines. Cohorts investigating FAI and concomitant hip OA Tönnis Grade 2 or more were considered eligible. Studies not written in English or German, below level 4 evidence, and reviews were excluded. A secondary analysis for FAI without OA stratification was conducted after the initial screening to allow identification of available non-operative interventions.

RESULTS

No study reported outcomes separately for non-operative management of FAI with Tönnis Grade 2 OA or more and as such, did not fulfil the inclusion criteria. A secondary analysis included 24 studies that reported on outcomes for non-operative interventions for FAI irrespective of the degree of degeneration. Three studies investigated the efficacy of hyaluronic acid injection, 5 reports investigated corticosteroid injections, 2 studies evaluated the outcomes of hip bracing and 16 studies included a physiotherapy programme. Associations between the aforementioned interventions were analysed. There is level I evidence supporting the efficacy of activity modification and hip-specific physiotherapy for FAI and mild OA. Core-strengthening exercises are prevalent amongst successful regimens in the literature. Contradictory evidence questions the efficacy of hip bracing even for short-term outcomes. Corticosteroid injections have mostly failed in intention-to treat analyses but may be valuable in delaying the need for surgery; further studies are warranted. Reports on outcomes following hyaluronic acid injections are contradictory.

CONCLUSION

No evidence exists on outcomes following non-operative management of FAI with concomitant Tönnis Grade 2 or more OA of the hip. Further studies are required and should explore the non-operative interventions that were employed for FAI and milder OA. There is strong evidence for a hip-specific physiotherapy program including activity modification and core strengthening exercises. Adjunct interventions such as corticosteroid injections and NSAID consumption may be valuable in delaying the need for surgery.

LEVEL OF EVIDENCE

Level IV.

Females with hip-related pain display altered lower limb mechanics compared to their healthy counterparts in a drop jump task

BACKGROUND

Hip-related pain describes femoroacetabular impingement syndrome, acetabular dysplasia, and other hip pain conditions without clear morphological features. Movement strategies in this population, notably sex-related patterns, are poorly understood and may provide insights into why females report more pain and worse function. This study examined the sex-related differences during a drop vertical jump task between those with hip-related pain and healthy controls.

METHODS

Patients with hip-related pain and healthy controls completed five repetitions of a drop jump while their kinematics and kinetics were recorded using a motion capture system and force plates. Hip, knee, and ankle joint angles and external joint moments during landing were used in general estimating equations for comparison of group by sex by limb interactions. Time series data were further investigated using statistical parametric mapping.

FINDINGS

Females with hip-related pain had 9.1° less hip flexion (P = .041) and 9.2° less knee flexion (P = .024) than healthy females, and 8.3° less knee flexion than male counterparts with hip-related pain (P = .039). Males demonstrated 1.4° less hip flexion on the affected side compared to their uninvolved side (P = .004). Statistical parametric mapping results showed significant differences in knee flexion angle for females with hip-related pain compared to healthy females (P = .042). There were no significant differences in hip, knee, or ankle moments.

INTERPRETATION

Females with hip-related pain showed kinematic patterns distinct from healthy controls. Sex may be an important variable of interest in characterizing movement impairments in this population and movement impairments may be an appropriate target for intervention for these patients.

Acetabular Cartilage Lesions Predict Inferior Mid-Term Outcomes for Arthroscopic Labral Repair and Treatment of Femoroacetabular Impingement Syndrome

PURPOSE

To analyze the effect of acetabular chondrosis at a minimum of 2 years following hip arthroscopy in patients undergoing labral repair and treatment of femoroacetabular impingement.

METHODS

From 2014 to 2017, patients undergoing arthroscopic labral repair were prospectively enrolled in a multicenter hip arthroscopy registry. The registry was retrospectively queried for primary labral repair patients with complete 2-year outcomes and a Tonnis grade of less than 2. Patients were grouped according to severity of articular cartilage damage noted intraoperatively using the Beck classification system: none, low-grade (Grade 1 or 2), or high-grade (Grade 3 or 4) damage. A Kruskal-Wallis test and post hoc Dunn's test with Holm correction compared 2-year postoperative outcome scores of the iHOT-12 scale between groups. The proportion of patients in each cohort who achieved the clinically significant thresholds of the minimum clinically important difference (MCID), patient-acceptable symptom scale, and substantial clinical benefit (SCB) were analyzed. Multivariate logistic regression models identified predictors of achieving clinical thresholds while controlling for demographic variation.

RESULTS

422 patients met inclusion criteria, from which 347 completed 2-year outcomes. All groups experienced improvement in iHOT-12 scores from baseline to follow-up (P < .001). iHOT-12 scores at follow-up were inferior for Low-Grade Damage and High-Grade Damage Groups relative to the No Damage Group (P = .04; P = .03). When accounting for age, body mass index, gender, and preoperative iHOT-12 scores in logistic regression models, the presence of high-grade lesions was a negative predictor for achieving SCB (OR [95% CI], 0.54 [0.29-0.96]) and low-grade lesions a negative predictor for achieving MCID (0.50 [0.27-0.92]. Among patients with high-grade lesions, there was no significant difference in 2-year iHOT-12 scores between those undergoing chondroplasty (n = 50) and those undergoing microfracture (n = 14) (P = .14).

CONCLUSIONS

Acetabular cartilage damage portends inferior patient-reported outcomes 2 years after primary labral repair and treatment of femoroacetabular impingement. The presence of cartilage lesions was a negative predictor of individual achievement of several clinical thresholds.

LEVEL OF EVIDENCE

III, Retrospective comparative cohort.

Symptom duration predicts inferior mid-term outcomes following hip arthroscopy

INTRODUCTION

Studies have demonstrated a negative relationship between the length of time with symptoms and patient-reported outcome measures in primary hip arthroscopy. Our aim was to expand the generalizability of this finding with a multi-center cohort.

METHODS

A multi-center hip arthroscopy registry was queried for patients undergoing primary hip arthroscopy from 2014 to 2017. Patients were stratified according to whether pre-operative symptom duration exceeded two years or did not exceed two years. A Wilcoxon rank sum test was performed for differences in two year post-operative outcome scores. Logistic regression models analyzed the influence of symptom duration on achieving clinically meaningful thresholds (minimum clinically important difference, patient-acceptable symptom state, substantial clinical benefit) when controlling for baseline scores, age, BMI, and sex.

RESULTS

Seven hundred forty-four patients met the inclusion criteria, from which 620 had complete outcomes information. The mean ± SD 2-year iHOT-12 scores of patients with symptom duration greater than two years (69 ± 26) were significantly lower than patients with symptom duration less than two years (77 ± 23) (Dunn test, p < 0.001). Chronic duration of pain was a negative predictor of achieving iHOT-12 MCID (0.47 [0.31-0.72]), PASS (0.53 [0.37-0.76]), and SCB (0.67 [0.47-0.94]).

CONCLUSION

When controlling for differences in baseline demographic factors and pre-operative iHOT-12 scores, patients with chronic pain report poorer functional outcomes at mid-term follow-up. These results suggest that chronic pain predicts inferior outcomes from primary hip arthroscopy and that surgical intervention at earlier time points may be beneficial in achieving better outcomes.

Presence of a Posterior Wall Sign in the Treatment of Femoroacetabular Impingement Syndrome: A Matched Comparative Cohort Analysis at Minimum 2-Year Follow-Up

BACKGROUND

Acetabular retroversion may predispose to more severe femoroacetabular impingement syndrome (FAIS) and early labral damage given impaction of the femoral head-neck junction on the retroverted acetabular rim. The cross-over sign (COS), posterior wall sign (PWS), and ischial spine sign (ISS) are markers of acetabular retroversion (AR) on plain radiographs.

METHODS

Patients who underwent primary hip arthroscopy for FAIS from January 2012 to December 2018 with a positive PWS were matched in a 1:1 ratio by age, gender, and body mass index (BMI) to controls with a negative PWS. Preoperative and postoperative patient-reported outcomes (PROs; HOS-ADL, HOS-SS, mHHS, and iHOT-12) were compared using independent t-tests. Achievement of a Patient Acceptable Symptom State (PASS) or Minimal Clinically Important Difference (MCID) was compared using Fisher's exact test.

RESULTS

Two hundred and seventy five patients with a positive PWS and 275 controls were included in the final analysis. Most patients (64%) were female, with average age, and BMI of 37.6 (SD 8.6) and 25.1 (SD 4.4), respectively. PROs improved significantly for both groups from preoperatively to 2 years postoperatively. There were no statistically significant differences (P ≥ .05) in PROs or achievement of MCID or PASS. On a subgroup analysis, patients with all three positive signs had significantly lower postoperative PROs and lower rates of achievement of MCID and PASS.

CONCLUSION

Patients with an isolated PWS achieve similar outcomes following hip arthroscopy at 2 years. However, patients with a concomitant PWS, ISS, and COS demonstrate less favorable outcomes, suggesting the need for increased perioperative counseling and potential evaluation for planned concurrent or serial open procedures such as periacetabular osteotomy.

Increased Readmission Rates but No Difference in Complication Rates in Patients Undergoing Inpatient Versus Outpatient Hip Arthroscopy: A Large Matched-Cohort Insurance Database Analysis

Purpose

Methods

Results

Conclusions

Level of Evidence

Do the outcomes of hip arthroscopy for femoroacetabular impingement change over time?

BACKGROUND

The purpose of this study was to search for changes in functional outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) between short and medium-term follow-up. Secondary aims included reporting rates of revision surgery and total hip arthroplasty (THA) at medium-term follow-up.

HYPOTHESIS

We hypothesised that patients' functional outcomes would improve between short and medium-term follow-up.

PATIENTS AND METHODS

Consecutive patients undergoing hip arthroscopy with a diagnosis of femoroacetabular impingement with labral tears between February 2013 and June 2015 were included. Twelve item international hip outcome tool (iHOT-12) and EuroQol 5D-5L (EQ-5D) scores were collected preoperatively, at short-term and medium-term follow-up. Short-term scores were recorded at a minimum of one year postoperatively and medium-term scores at a minimum of five years postoperatively. Survivorship was assessed with Kaplan-Meier analysis.

RESULTS

Short-term outcome data (at median follow-up 1.6 year, Interquartile range [IQR] 1-2.5) was available for 70 of 87 patients (80.5%) and medium-term outcome data (at median follow-up of 6.5 years, IQR 6-7.1) was available for 68 patients (78.2%). Median age at the time of surgery was 31 years (IQR 25-37). The median iHOT-12 scores at short and medium-term follow-up were 72 (IQR 48.75-91.25) and 85.8 (IQR 66.7-96.7) respectively (p<0.001). Medium-term survivorship was 91.2%. Survivorship following labral repair was 94.2%, and 81.3% following labral debridement (p=0.09).

DISCUSSION

Patients undergoing hip arthroscopy for FAI reported continued improvement in iHOT-12 scores between short and medium-term follow-up. Medium-term survivorship following FAI surgery may be greater when the labrum is repaired, although comparisons are limited by their differing indications. Conversion to THA was low with just 4 patients (4.6%) undergoing or being listed for THA at final follow-up.

LEVEL OF EVIDENCE

IV, Case series.

Pre- and intraoperative decision-making challenges in hip arthroscopy for femoroacetabular impingement

There has been a marked increase in the number of hip arthroscopies performed over the past 16 years, primarily in the management of femoroacetabular impingement (FAI). Insights into the pathoanatomy of FAI, and high-level evidence supporting the clinical effectiveness of arthroscopy in the management of FAI, have fuelled this trend. Arthroscopic management of labral tears with repair may have superior results compared with debridement, and there is now emerging evidence to support reconstructive options where repair is not possible. In situations where an interportal capsulotomy is performed to facilitate access, data now support closure of the capsule in selective cases where there is an increased risk of postoperative instability. Preoperative planning is an integral component of bony corrective surgery in FAI, and this has evolved to include computer-planned resection. However, the benefit of this remains controversial. Hip instability is now widely accepted, and diagnostic criteria and treatment are becoming increasingly refined. Instability can also be present with FAI or develop as a result of FAI treatment. In this annotation, we outline major current controversies relating to decision-making in hip arthroscopy for FAI. Cite this article: Bone Joint J 2022;104-B(5):532-540.

Incidence of heterotopic ossification following hip arthroscopy is low: considerations for routine prophylaxis

PURPOSE

This scoping review aims to map and summarise the available literature on heterotopic ossification (HO) following hip arthroscopy, with particular focus on incidence, distribution as per Brooker classification, efficacy of prophylactic measures and factors that may influence the likelihood of production of HO.

METHODS

A computer-based search was performed on PubMed, Embase, Emcare, Cinahl, ISI web of science and Scopus using the terms 'heterotopic ossification' and 'hip arthroscopy'. Articles reporting heterotopic ossification following hip arthroscopy for any condition were included after two-stage title/abstract and full-text screening.

RESULTS

Of the 663 articles retrieved, 45 studies were included. The proportion of patients with HO ranged from 0 to 44%. The majority of the cases were either Brooker grade I or II. Of the six studies investigating the effect of NSAID prophylaxis, five reported a significantly lower incidence of heterotopic ossification associated with its use. Weak evidence suggests that an outside-in arthroscopic approach, no capsular closure, male sex and mixed cam and pincer resection may be associated with an increased risk of HO.

CONCLUSION

Although there is a large variation in rates of HO following hip arthroscopy in the current literature, the majority of studies report a low incidence. Evidence exists advocating the administration of post-operative NSAIDs to reduce the incidence of HO following hip arthroscopy. This, combined with the low risk of complications, means there is a favourable risk-benefit ratio for prophylactic NSAID used in HA. Future research should work to identify patient clinical and demographic factors which may increase the risk of development of HO, allowing clinicians to risk stratify and select only specific patients who would benefit from receiving NSAID prophylaxis.

Ten-Year Outcomes After Hip Arthroscopy in Patients With Femoroacetabular Impingement and Borderline Dysplasia

BACKGROUND

The role of hip arthroscopy in the treatment of patients with borderline hip dysplasia is controversial and evolving.

PURPOSE

To evaluate outcomes at a minimum 10-year follow-up in patients who underwent hip arthroscopy for femoroacetabular impingement in a hip with borderline dysplasia.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All hips that underwent labral repair between June 2006 and March 2009 for femoroacetabular impingement with borderline dysplasia were included if they had a lateral center-edge angle of 20° to 25°, had primary hip arthroscopy for the diagnosis of femoroacetabular impingement, and were aged 18 to 70 years. Patients were excluded if they had previous hip surgery, avascular necrosis, or fracture. Kaplan-Meier survivorship was performed, with survivorship defined as avoidance of conversion to total hip arthroplasty (THA).

RESULTS

A total of 45 patients met the inclusion criteria, and 38 were contacted at a minimum 10 years postoperatively (84%; mean ± SD, 12 ± 1.3 years). There were 23 women and 15 men with an average age of 41 ± 9.6 years (range, 25-69). Twenty patients were ≥40 years of age. In this patient cohort, survivorship was 87% at 5 years and 79% at 10 years for conversion to THA. Of the 38 patients included, 9 were converted to THA (24%), and 3 required revision hip arthroscopy (7%). Patient age, Tönnis grade, microfracture of cartilage lesions, and Tönnis angle >15° were associated with conversion to THA. No statistically significant differences were found between those who underwent conversion to THA and those who did not regarding lateral center-edge angle, Sharp angle, or alpha angle. Significant improvements were seen at follow-up of 12 years (range, 10-13) for the modified Harris Hip Score (58 to 83; P = .002), Hip Outcome Score-Activities of Daily Living (70 to 87; P = .003), Hip Outcome Score-Sport (47 to 76; P = .004), and Western Ontario and McMaster Universities Osteoarthritis Index (31 to 10; P = .001). At follow-up, >80% maintained the minimal clinically important difference for the Hip Outcome Score (Activities of Daily Living and Sport) with no differences between patients aged <40 and ≥40 years.

CONCLUSION

Risk factors for conversion to THA after hip arthroscopy in the borderline dysplastic hip included older age, higher Tönnis grades, grade 4 chondral lesions that were microfractures, and Tönnis angle >15°. In those patients who did not convert to THA, improvement in outcome measures was seen at 10 years. Careful patient selection is critical to the success of this procedure.

Equality in Hip Arthroscopy Outcomes Can Be Achieved Regardless of Patient Socioeconomic Status

BACKGROUND

Access to quality health care and treatment outcomes can be affected by patients' socioeconomic status (SES).

PURPOSE

To evaluate the effect of patient SES on patient-reported outcome measures (PROMs) after arthroscopic hip surgery.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Demographic, radiographic, and intraoperative data were prospectively collected and retrospectively reviewed on all patients who underwent hip arthroscopy for femoroacetabular impingement syndrome (FAIS) and labral tear between February 2008 and September 2017 at one institution. Patients were divided into 4 cohorts based on the Social Deprivation Index (SDI) of their zip code. SDI is a composite measure that quantifies the level of disadvantage in certain geographical areas. Patients had a minimum 2-year follow-up for the modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), International Hip Outcome Tool-12, and visual analog scale (VAS) for both pain and satisfaction. Rates of achieving the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were calculated for the mHHS, NAHS, and VAS pain score. Rates of secondary surgery were also recorded.

RESULTS

A total of 680 hips (616 patients) were included. The mean follow-up time for the entire cohort was 30.25 months. Division of the cohort into quartiles based on the SDI national averages yielded 254 hips (37.4%) in group 1, 184 (27.1%) in group 2, 148 (21.8%) in group 3, and 94 (13.8%) in group 4. Group 1 contained the most affluent patients. There were significantly more men in group 4 than in group 2, and the mean body mass index was greater in group 4 than in groups 1 and 2. There were no differences in preoperative radiographic measurements, intraoperative findings, or rates of concomitant procedures performed. All preoperative and postoperative PROMs were similar between the groups, as well as in the rates of achieving the MCID or PASS. No differences in the rate of secondary surgeries were reported.

CONCLUSION

Regardless of SES, patients were able to achieve significant improvements in several PROMs after hip arthroscopy for FAIS and labral tear at the minimum 2-year follow-up. Additionally, patients from all SES groups achieved clinically meaningful improvement at similar rates.

Association Between Comorbid Depression and Rates of Postoperative Complications, Readmissions, and Revision Arthroscopic Procedures After Elective Hip Arthroscopy

Background:

Depression and related psychiatric diagnoses are common in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS). The effects of depression on postoperative complications, readmissions, and additional ipsilateral hip surgery are not well studied.

Hypothesis:

Patients with preoperative depression who undergo hip arthroscopy for FAIS would experience higher rates of 90-day postoperative complications and readmissions, with an increased risk of additional ipsilateral hip procedures, as compared with patients without depression.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective cohort study between 2010 and 2019 was performed using the Mariner/PearlDiver database. Current Procedural Terminology and International Classification of Diseases codes were used to compare patients with and without preexisting depression who underwent hip arthroscopy for FAIS. Patients were matched at a 1:1 ratio based on age, sex, Charlson Comorbidity Index, body mass index, and tobacco use. Patients undergoing shoulder or knee arthroscopy were also identified to compare lifetime preoperative depression prevalence amongst groups.

Results:

The lifetime preoperative depression prevalence was significantly higher in patients undergoing hip arthroscopy as compared with patients undergoing shoulder or knee arthroscopy (25.4% vs 22.2% vs 19.8%; P < .001). When compared with the patients without depression, patients with preoperative depression had higher rates of 90-day readmissions (2.4% vs 1.5%) and complications, including urinary tract infection (36.2% vs 28.9%), pneumonia (12.9% vs 9.1%), hematoma formation (3.1% vs 1.9%), acute kidney injury (4.0% vs 2.6%), deep venous thrombosis/pulmonary embolism (2.6% vs 1.7%), and superficial infection (4.9% vs 2.8%; P < .01 for all comparisons). Preoperative depression was associated with significantly higher odds of undergoing revision hip arthroscopy within 2 years (6.3% vs 2.4%; P < .001).

Conclusion:

Patients with preexisting depression experienced higher rates of 90-day postoperative complications and hospital readmissions after elective hip arthroscopy for FAIS and were more likely to undergo revision hip arthroscopy within 2 years of the index procedure.

The role of iliocapsularis in hip pathology: a scoping review

The iliocapsularis is a relatively unheard-of muscle, located deep in the hip covering the anteromedial capsule of the hip joint. Little is known about this constant muscle despite its clinical relevance. The aims of this scoping review are to collate the various research studies reporting on the detailed anatomy and function of iliocapsularis and to demonstrate how inter-individual differences in iliocapsularis can be used as a clinical adjunct in guiding diagnosis and treatment of certain hip joint pathologies. A computer-assisted literature search was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Our review found 13 studies including 384 cases meeting our inclusion criteria. About 53.8% of the studies involved human cadavers. The current scoping review indicates the relevant anatomy of the iliocapsularis, being a small muscle which arises from the inferior border of the anterior inferior iliac spine and anteromedial capsule of the hip joint, inserting distal to the lesser trochanter. Therefore, based upon these anatomical attachments, iliocapsularis acts as a dynamic stabilizer by tightening the anterior capsule of the hip joint. Implications of this association may be that the muscle is hypertrophied in dysplastic or unstable hips. Determining the size of the iliocapsularis could be of conceivable use in patients with hip symptoms featuring signs of both borderline hip dysplasia and subtle cam-type deformities. Although future research is warranted, this study will aid physicians to understand the clinical importance of the iliocapsularis.

Endoscopic Iliotibial Band Release During Hip Arthroscopy for Femoroacetabular Impingement Syndrome and External Snapping Hip Had Better Patient-Reported Outcomes: A Retrospective Comparative Study

PURPOSE

To compare patient-reported outcomes (PROs) in patients with femoroacetabular impingement (FAI) syndrome and external snapping hip (ESH) treated with hip arthroscopy with or without endoscopic iliotibial band (ITB) release.

METHODS

Retrospective review case series with both FAI syndrome and ESH who underwent surgical treatment under same indications. According to the primary operation that was determined by patients themselves, the patients undergoing ITB release during hip arthroscopy for FAI syndrome were enrolled in the ITB-R group, and patients undergoing hip arthroscopy without ITB release were enrolled in non-ITB-R group. Patients with dysplasia, severe osteoarthritis, revision, and bilateral surgery were excluded. PROs including international Hip Outcome Tool (iHOT-33), modified Harris Hip Score (mHHS), visual analog scale for pain (VAS-pain) and VAS-satisfaction, and the rates of achieving minimal clinically important difference, patient acceptable symptomatic state (PASS), and substantial clinical benefit for the PROs at 2 years operatively were comparative analyzed.

RESULTS

The prevalence of ESH in patients with FAI syndrome who underwent hip arthroscopy in our institution was 4.9% (30 of 612 hips). The mean age at the time of surgery was 33.1 ± 6.9 years (range 22-48 years). After exclusion, 16 patients (16 hips) were enrolled into ITB-R group and 11 patients (11 hips) enrolled into non-ITB-R group. PROs including iHOT-33, mHHS, VAS-pain, and VAS-satisfaction in patients in ITB-R group were better than that in non-ITB-R group at 2 years postoperatively (P = .013, .016, .002, and .005, respectively). The rates of achieving PASS for mHHS, PASS for VAS-pain, and substantial clinical benefit for iHOT-33 of patients in ITB-R group were significantly better than that in non-ITB-R group (P = .009, .006, and .027, respectively).

CONCLUSIONS

Patients with both FAI syndrome and ESH undergoing ITB release during hip arthroscopy had better PROs than those undergoing hip arthroscopy without ITB release.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Editorial Commentary: Predicting Satisfaction After Hip Arthroscopy Using Machine Learning: What Do Treadmills and Black Boxes Have to Do With Arthroscopy?

The use of advanced statistical methods and artificial intelligence including machine learning enables researchers to identify preoperative characteristics predictive of patients achieving minimal clinically important differences in health outcomes after interventions including surgery. Machine learning uses algorithms to recognize patterns in data sets to predict outcomes. The advantages are the ability, using "big data" registries, to infer relations that otherwise would not be readily understood and the ability to continuously improve the model as new data are added. However, machine learning has limitations. Models are only as good as the data incorporated, and data may be misapplied owing to huge data sets and strong computing capabilities, in which spurious correlations may be suggested based on significant P values. Hence, common sense must be applied. The future of outcome prediction studies will most definitely rely on machine learning and artificial intelligence methods.

The influence of pain catastrophizing and central sensitization on the reported pain after hip arthroscopy

PURPOSE

This study was conducted to investigate whether the pain catastrophizing scale (PCS) and the central sensitization inventory (CSI) are predictive factors for the reported pain after hip arthroscopy.

METHODS

A total of 37 patients undergoing hip arthroscopy for femoroacetabular impingement syndrome and labral tears were prospectively enrolled. All patients completed the PCS and CSI before hip arthroscopy. Postoperative pain was measured with the numeric rating scale (NRS) weekly the first 12 weeks after surgery by electronic diary.

RESULTS

At baseline, univariate analyses showed that both the CSI and PCS were significantly associated with the NRS outcome (p < 0.01). During 12 weeks follow-up, a significant decrease on the NRS was observed (p < 0.01). Univariate analyses showed that both the CSI and PCS were significantly associated with the NRS during follow-up. Multivariate mixed model analysis showed that only the PCS remained significantly associated with the NRS outcome with a ß of 0.07 (95% CI 0.03-0.11, p < 0.01).

CONCLUSION

Results indicate that both the PCS and CSI are associated with the reported postoperative pain after hip arthroscopy. The PCS and CSI may be useful in daily practice to identify patients that possibly benefit from pain catastrophizing reduction therapy (e.g. counseling) prior to surgery.

LEVEL OF EVIDENCE

IV.

Predicting Subjective Recovery from Lower Limb Surgery Using Consumer Wearables

Introduction

A major challenge in the monitoring of rehabilitation is the lack of long-term individual baseline data which would enable accurate and objective assessment of functional recovery. Consumer-grade wearable devices enable the tracking of individual everyday functioning prior to illness or other medical events which necessitate the monitoring of recovery trajectories.

Methods

For 1,324 individuals who underwent surgery on a lower limb, we collected their Fitbit device data of steps, heart rate, and sleep from 26 weeks before to 26 weeks after the self-reported surgery date. We identified subgroups of individuals who self-reported surgeries for bone fracture repair (n = 355), tendon or ligament repair/reconstruction (n = 773), and knee or hip joint replacement (n = 196). We used linear mixed models to estimate the average effect of time relative to surgery on daily activity measurements while adjusting for gender, age, and the participant-specific activity baseline. We used a sub-cohort of 127 individuals with dense wearable data who underwent tendon/ligament surgery and employed XGBoost to predict the self-reported recovery time.

Results

The 1,324 study individuals were all US residents, predominantly female (84%), white or Caucasian (85%), and young to middle-aged (mean age 36.2 years). We showed that 12 weeks pre- and 26 weeks post-surgery trajectories of daily behavioral measurements (steps sum, heart rate, sleep efficiency score) can capture activity changes relative to an individual's baseline. We demonstrated that the trajectories differ across surgery types, recapitulate the documented effect of age on functional recovery, and highlight differences in relative activity change across self-reported recovery time groups. Finally, using a sub-cohort of 127 individuals, we showed that long-term recovery can be accurately predicted, on an individual level, only 1 month after surgery (AUROC 0.734, AUPRC 0.8). Furthermore, we showed that predictions are most accurate when long-term, individual baseline data are available.

Discussion

Leveraging long-term, passively collected wearable data promises to enable relative assessment of individual recovery and is a first step towards data-driven intervention for individuals.