Isolated Endoscopic Gluteus Medius Repair Can Achieve Successful Clinical Outcomes at Minimum 2-Year Follow-up

Comparable Pain Levels and Functional Outcomes With and Without the Use of Dermal Allograft Augmentation in Endoscopic Gluteus Medius Repair

PURPOSE

To compare retrospectively the clinical outcomes of patients undergoing endoscopic gluteal tendon repair with and without the use of dermal allograft augmentation.

METHODS

A retrospective review of prospectively collected data, single-surgeon cohort study was performed on all patients undergoing endoscopic gluteus medius repair (GMR) and GMR with augmentation (GMR-A) between April 2017 and April 2022. Dermal allograft augmentation was used in cases where intraoperative gluteus tissue quality was poor. An electronic survey of patient-reported outcome measures (PROMs) was completed at a minimum of 1 year postoperatively. PROMs included a visual analog scale (VAS) for pain; the University of California, Los Angeles (UCLA) Activity Scale; the modified Harris Hip Score (mHHS); the Hip Outcome Score-Sport-Specific Subscale (HOS-SSS); and the Single Assessment Numeric Evaluation (SANE). The proportion of patients achieving the minimal clinically important difference (MCID), patient acceptable symptom state (PASS), and substantial clinical benefit (SCB) for each PROM were compared between groups.

RESULTS

Sixty-four patients were reached for follow-up (26 GMR, 38 GMR-A). No differences were found between the groups in terms of demographics. There was a significantly longer time to follow-up in the GMR group (39.4 ± 26.9 vs 24.2 ± 11.7 months, P = .003). There were no differences between the GMR and GMR-A groups in terms of postoperative PROMs including VAS (3.3 ± 2.6 vs 3.3 ± 2.8, P = .99), UCLA (5.8 ± 2.1 vs 5.1 ± 2.0, P = .17), mHHS (70.1 ± 18.1 vs 68.9 ± 17.8, P = .80), HOS-SSS (67.7 ± 28.9 vs 62.5 ± 30.2, P = .50), and SANE (71.7 ± 27.9 vs 71.3 ± 22.8, P = .95). A significantly greater proportion of patients in the GMR group achieved a PASS for UCLA (64% vs 34%, P = .02). One patient each in the GMR (3.8%) and GMR-A (2.6%) groups underwent revision gluteus medius repair with dermal allograft augmentation at the final follow-up.

CONCLUSIONS

Our study demonstrates comparable clinical outcomes with and without the use of dermal allograft augmentation in endoscopic gluteus medius repairs.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Editorial Commentary: Endoscopic Repair of Abductor Tendon Tears Results in Variable Patient Reported Outcomes and Generally Good to Excellent Results

Abductor tendon pathology is fairly common, with up to a 25% incidence in patients having total hip arthroplasty and 30% having hip arthroscopy. A systematic review of endoscopic abductor tendon repair demonstrated that as few as 41% of patients with endoscopic repair of abductor tendon tears achieve a patient acceptable satisfactory state, but a major limitation of systematic reviews is extreme heterogeneity between included studies. Surgical techniques and skills differ, as do tear severity and confounding pathology such as labral tears. Another limitation is a focus on patient-reported outcome measures (PROMs). PROMs are important (we prefer happy patients with poor healing to unhappy patients with healed repairs), but PROMs are also "subjective," and different cohorts of patients in different studies from different locations may have different perceptions or goals with regard to pain and function. As surgeons, we are able to observe gait, strength, and, with advanced imaging when indicated or for research purposes, healing. These, combined with PROMs, influence overall assessment of outcome. Experience and review of the literature show that endoscopic surgical repair of abductor tendon tears generally shows good or excellent results. If a patient has significant pain improvement and objectively improved gait, a calculation of an outcome threshold based on a subjective survey may not tell the full story.

Forty-One to 75% of Patients Achieve a Patient Acceptable Symptomatic State After Endoscopic Repair of Hip Abductor Tendon Tears: A Systematic Review

PURPOSE

To systematically review clinical and functional outcomes of endoscopic repairs of hip abductor tendon tears.

METHODS

A search following guidelines established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses was performed in the PubMed, Embase, and Cochrane databases using variations of the terms "endoscopy," "gluteus medius," "hip abductor," "outcome," "success," and "failure." Data for patient demographics, tear severity and location, patient-reported outcomes (PROs), clinical benefit, and rates of retears and revision surgery were collected and tabulated. Forest plots depicting preoperative versus postoperative PROs were generated. Quality assessment was performed using the modified Coleman Methodology Score.

RESULTS

In total, 13 studies, 3 Level III and 10 Level IV, were included in this review, with a total of 272 patients whose ages ranged from 46.0 to 66.9 years and follow-up times from 16.4 to 46.7 months. Most tears were isolated to the gluteus medius, with the number of partial- versus full-thickness tears being similar. Trendelenburg gait, reported by 4 studies, persisted in 0% to 13.6% of patients after repair. Of 9 studies reporting both preoperative and postoperative PROs at latest follow-up, 8 reported significant improvements in all PROs (P < .05). In 5 studies, rates of achieving minimal clinically important difference and patient-acceptable symptomatic state ranged from 50.0% to 93.3% and 40.7% to 75.0%, respectively. Surgical complication rates were 0% in 11 studies and 4.3% and 18.2% in 2 studies. Retear rates were 0% in 10 studies and ranged from 6.7% to 33.3% in 3 studies. Rates of revision due to retear, reported by 12 studies, were 0% in 8 studies and ranged from 2.2% to 13.0% in 4studies.

CONCLUSIONS

Endoscopic repairs of both partial- and full-thickness hip abductor tendon tears have good-to-excellent PROs and low complication, retear, and revision rates. However, rates of minimal clinically important difference and patient-acceptable symptomatic state achievement rates are highly variable and less than favorable.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and IV studies.

Gluteus Repair Yields Satisfactory Clinically Significant Outcome Achievement by 1 Year in Mostly Partial-Thickness Tears With Preoperative Hip Abduction Weakness Associated With Delayed Achievement

PURPOSE

To define the time to achievement of clinically significant outcomes (CSOs) after primary gluteus medius and/or minimus (GM) repair and to identify factors associated with delayed CSO achievement.

METHODS

Patients who underwent primary GM repair between January 2012 and June 2021 with complete preoperative, 6-month, 1-year, and 2-year Hip Outcome Score-Activities of Daily Living (HOS-ADL) were retrospectively identified. Cohort-specific minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were calculated. The time to achievement of MCID and PASS was analyzed using Kaplan-Meier survival analysis. Median time to MCID and PASS achievement was recorded. Multivariate stepwise Cox regressions were used to identify factors associated with delayed CSO achievement.

RESULTS

Fifty GM repairs were identified (age 59.4 ± 9.7 years, body mass index 27.9 ± 6.2, 94% female). Tears were grade 1 in 39 cases, grade 2 in 7 cases, and grade 3 in 4 cases. Endoscopic repair was performed in 35 cases, and open repair was performed in 15 cases. Labral debridement and repair were each performed in 15 cases. Median time to CSO achievement was 5.7 months for MCID and 11.0 months for PASS. The 2-year cumulative probability of MCID and PASS achievement was 92.7% and 66.7%, respectively. Preoperative hip abduction weakness on physical examination was associated with delayed achievement of MCID (hazard ratio 2.27, confidence interval 1.067-7.41, P = .039) and PASS (hazard ratio 3.89, confidence interval 1.341-11.283, P = .012).

CONCLUSIONS

This study demonstrated that in patients undergoing repair of primarily grade 1 GM tears, most achieved MCID by 6 months, and more than one half achieved PASS by 12 months. Preoperative hip abduction weakness on physical examination was associated with delayed CSO achievement.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Outcomes of Isolated Endoscopic Gluteal Tendon Repair Compared With Concomitant Endoscopic Gluteal Tendon Repair and Arthroscopic Hip Labral Repair: A Propensity-Matched Analysis With Minimum 2-Year Follow-up

Background

Both gluteal and labral tears are common sources of hip pain, but no studies have evaluated how concomitant arthroscopic labral repair and correction of femoroacetabular impingement syndrome (FAIS) affect outcomes after endoscopic gluteus/minimus repair.

Purpose

(1) To compare patient-reported outcomes (PROs) and clinically significant outcomes achievements between patients who underwent endoscopic gluteus medius/minimus and arthroscopic hip labral repair with correction of FAIS versus endoscopic gluteus medius/minimus repair without labral repair and (2) to define threshold scores required to achieve the minimal clinically important difference (MCID) and the Patient Acceptable Symptom State (PASS) for the Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Specific, modified Harris Hip Score (mHHS), 12-item international Hip Outcome Tool, and visual analog scale for pain in these patients.

Study Design

Cohort study; Level of evidence, 3.

Methods

Patients who underwent primary endoscopic gluteus medius/minimus repair between 2012 and 2020 were identified. Those who underwent concomitant arthroscopic labral repair and correction of FAIS with femoroplasty or acetabuloplasty as indicated were propensity matched in a 1 to 1 ratio by sex, age, and body mass index to patients who underwent gluteus medius/minimus repair without labral repair. Patients who completed the study PROs were assessed preoperatively and at 2 years postoperatively. Threshold scores required to achieve the MCID and PASS thresholds were calculated.

Results

A total of 32 patients who underwent simultaneous gluteal and labral repair (G+L) were matched to 32 patients who underwent gluteal repair without labral repair (G); 75% of patients in the G cohort underwent labral debridement, while 25% in this cohort received no labral treatment. A significant difference was observed between groups in preoperative mHHS scores (G+L, 54.4 ± 12.9 vs G, 46.3 ± 14; P = .048) but no differences in any other PRO scores (P≥ .207). The MCID/PASS thresholds were as follows: Hip Outcome Score-Activities of Daily Living (11.14/83.82), Hip Outcome Score-Sports Specific (16.07/59.72), mHHS (11.47/70.95), 12-item international Hip Outcome Tool (13.73/45.49), and visual analog scale for pain (14.30/22). There were no significant differences in MCID or PASS achievement rates between the 2 groups (P≥ .108).

Conclusion

Patients who underwent combined G+L demonstrated comparable PROs and clinically significant outcomes achievement rates to patients who underwent G, highlighting sustained successful outcomes for patients with gluteal tendon pathology and concomitant FAIS and labral tears.

The Gluteus-Score-7 Predicts the Likelihood of Both Clinical Success and Failure Following Surgical Repair of the Hip Gluteus Medius and/or Minimus

PURPOSE

To identify patient preoperative history, examination, and imaging characteristics that increase the risk of postoperative failure of gluteus medius/minimus repair, and to develop a decision-making aid predictive of clinical outcomes for patients undergoing gluteus medius/minimus repair.

METHODS

Patients from 2012 to 2020 at a single institution undergoing gluteus medius/minimus repair with minimum 2-year follow-up were identified. MRIs were graded according to the "three-grade" classification system: grade 1: partial-thickness tear, grade 2: full-thickness tears with <2 cm of retraction, grade 3: full-thickness tears with ≥2 cm retraction. Failure was defined as undergoing revision within 2 years postoperatively or not achieving both a cohort-calculated minimal clinically important difference (MCID) and responding "no" to patient acceptable symptom state (PASS). Inversely, success was defined as reaching both an MCID and responding "yes" to PASS. Predictors of failure were verified on logistic regression and a predictive scoring model, the Gluteus-Score-7, was generated to guide treatment-decision making.

RESULTS

In total, 30 of 142 patients (21.1%) were clinical failures at mean ± SD follow-up of 27.0 ± 5.2 months. Preoperative smoking (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.0-8.4; P = .041), lower back pain (OR, 2.8; 95% CI, 1.1-7.3; P = .038), presence of a limp or Trendelenburg gait (OR, 3.8; 95% CI, 1.5-10.2; P = .006), history of psychiatric diagnosis (OR, 3.7; 95% CI, 1.3-10.8; P = .014), and increased MRI classification grades (P ≤ .042) were independent predictors of failure. The Gluteus-Score-7 was generated with each history/examination predictor assigned 1 point and MRI classes assigned corresponding 1-3 points (min 1, max 7 score). A score of ≥4/7 points was associated with risk of failure and a score ≤2/7 points was associated with clinical success.

CONCLUSIONS

Independent risk factors for revision or not achieving either MCID or PASS after gluteus medius and/or minimus tendon repair include smoking, preoperative lower back pain, psychiatric history, Trendelenburg gait, and full-thickness tears, especially tears with ≥2 cm retraction. The Gluteus-Score-7 tool incorporating these factors can identify patients at risk of both surgical treatment failure and success, which may be useful for clinical decision-making.

LEVEL OF EVIDENCE

Level IV, prognostic case series.

Survivorship, Outcomes, and Risk Factors for Conversion to Total Hip Arthroplasty After Revision Hip Arthroscopic Surgery in Obese Patients: Results at a Minimum 5-Year Follow-up

Background

There is a paucity of literature reporting outcomes after revision hip arthroscopic surgery in obese patients.

Purpose

To report the minimum 5-year survivorship, patient-reported outcomes (PROs), clinical benefit, and risk factors for conversion to total hip arthroplasty (THA) in obese patients after revision hip arthroscopic surgery.

Study Design

Case series; Level of evidence, 4.

Methods

Data were prospectively collected and retrospectively reviewed for patients who underwent revision hip arthroscopic surgery by a single surgeon between April 2010 and August 2016. Inclusion criteria were a body mass index ≥30 and baseline and minimum 5-year postoperative values for the modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), Hip Outcome Score-Sport-Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain. Exclusion criteria were Tönnis grade >1 and hip dysplasia. Survivorship was defined as no conversion to THA. Clinical benefit was measured using the minimal clinically important difference (MCID). Survivors and nonsurvivors underwent further bivariate and regression analyses to determine the predictors of conversion to THA.

Results

Included were 24 hips in 24 patients. The mean patient age was 39.3 ± 12.7 years, and the mean follow-up was 83.9 ± 26.5 months. The survivorship rate was 75.0%, and patients demonstrated a significant improvement in all PROs (P < .01). At 5-year follow-up, the MCID for the mHHS, NAHS, HOS-SSS, and VAS was achieved by 70.6%, 94.1%, 92.9%, and 64.7%, respectively, of the patients. Older age, higher grade ligamentum teres tears, and acetabuloplasty were significant on bivariate analysis for conversion to THA, and increased age was identified as a significant variable for conversion to THA on regression analysis (odds ratio, 1.297 [95% CI, 1.045-1.609]; P = .018), with a 29.7% greater risk for every additional year of age at the time of revision.

Conclusion

In this study, 25.0% of obese patients who underwent revision hip arthroscopic surgery required conversion to THA. The study patients who did not need conversion to THA had a significant improvement in all PROs, with >90% achieving MCID for one or more outcome measures. Older age was identified as a significant predictor of conversion to THA.

Endoscopic Gluteus Medius Repair

Endoscopic gluteus medius repair is indicated after failed conservative management for debilitating peritrochanteric hip pain. In our experience, most of these surgeries are performed on women, 45 to 75 years old. Often for undersurface high-grade partial-thickness tears and some small full-thickness tears, a single-row repair technique is performed. For larger, full-thickness tears, a double-row repair is often performed. For minimal, superficial, partial-thickness tears with a longitudinal component of tearing through the gluteus medius tendon, a side-to-side repair is performed. Short-term follow-up shows significant improvements in hip outcome score for activities of daily living and in numeric rating scale.

Satisfactory results after endoscopic gluteus medius repair combined with selective gluteus maximus reflected tendon release for the treatment of a full-thickness tear of gluteus medius

PURPOSE

The current study aimed to report the mid-term follow-up results of endoscopic gluteus medius repair combined with a systematic release of the gluteus maximus reflected tendon.

METHODS

Twenty-two patients with a symptomatic full-thickness tear of the gluteus medius tendon, as diagnosed by clinical examination and imaging (MRI), and who had a failure of conservative treatment for at least 6 months, were retrospectively enrolled for this study. An endoscopic repair of gluteus medius was performed for all patients in combination with gluteus maximus reflected tendon release according to the Polesello technique. The Visual Analogue Scale (VAS) for pain, Modified Harris Hip Score (mHHS), Lower Extremity Functional Scale (LEFS), Hip Outcome Score-Activity Daily Life (HOS-ADL), and Hip Outcome Score-Sport Specific Subscale (HOS-SSS) were administered to each patient before surgery for 6 months, 1 year, and every following year after surgery.

RESULTS

All analysed hip scores (mHHS, LEFS, HOS-ADL, and HOS-SSS) showed statistically significant improvements between the pre-operative and post-operative values at 6 months, 1 year, and the latest follow-up appointments after surgery (p < 0.001). The mean pre-operative pain was 8.6 ± 1.0 on the VAS. After surgical treatment, the pain was significantly reduced (p < 0.001) on the VAS at 6 months (5.4 ± 1.5), 1 year (4.4 ± 1.8) and the latest follow-up control visit (3.6 ± 2.2). No patient-reported major complications (re-rupture, deep infection or neurovascular injury). Eleven (50%) patients indicated the results as excellent, 7 (32%) as good, 2 (9%) as fair, and 2 (9%) as poor.

CONCLUSION

The use of abductor tendon repair in combination with a systematic release of the reflected tendon of the gluteus maximus according to the Polesello technique seems to be a safe and effective endoscopic way of treating a full-thickness tear of the gluteus medius.

LEVEL OF EVIDENCE

Level IV.

Gluteus Maximus Transfer following Total Hip Arthroplasty Does Not Improve Abductor Moment: A Case-Control Gait Analysis Study of 15 Patients with Gluteus Medius Disruption

Gluteus maximus flap transfer (GMT) is a surgical technique used to improve gait kinematics and kinetics, as well as to reduce and ameliorate the functional outcome in patients with hip abductor deficiency following total hip arthroplasty (THA). The purpose of this observational study was to evaluate the gait pre- and postoperatively and examine whether GMT increases the abduction moment. Materials and Methods: A gait analysis based on reflective markers and force plates was performed in 15 patients who underwent GMT and were examined using an optical tracking system before and at a minimum of 13 months after the operation. The median follow-up time was 24 (13−60) months. The primary outcome was hip abduction moment (Nm/kg) during gait. The control group consisted of 15 female subjects without any gait pathology. Results: The mean adduction moment was significantly higher compared with controls before the operation (p = 0.02), but this did not apply to the abduction moment (p = 0.60). At the group level, the abduction moment did not improve postoperatively (p = 0.30). Only six of fifteen patients slightly improved their hip abduction moment postoperatively. However, speed (0.74 to 0.80 m/s) and cadence (94 to 105 steps/min) were improved (p < 0.03). Discussion: The results of this study showed no improvement in the hip abduction moment after GMT surgery. In our experience, abduction deficiency following primary THA is still a difficult and unsolved problem.