Anatomy and dimensions of the gluteus medius tendon insertion

High Rate of Concomitant Lumbo-Sacral Spine Pathology in the Setting of Hip Abductor Tendon Repair

BACKGROUND

Hip abductor deficiency is a common cause of lateral hip pain in middle-aged patients. Identifying upstream muscle denervation originating in the lumbo-sacral spine could potentially impact the management of patients who have abductor deficiency. The purpose of this study was to estimate the prevalence of lumbo-sacral pathology (L4 to S1) in patients undergoing hip abductor tendon repair.

METHODS

All cases of primary hip abductor repair performed at a tertiary care center between January 2010 and December 2021 were reviewed. Patients were classified into the following groups: A) confirmed L4 to S1 disease based on preoperative or perioperative L4 to S1 interventions (ie, surgery, epidural injections, and/or positive electromyography findings); B) radiographic evidence on lumbar spine magnetic resonance imaging demonstrating nerve compression at L4 to S1; and C) no evidence of L4 to S1 disease.

RESULTS

There were 131 cases of primary hip abductor repair that were included. Over 80% of patients were women, who had a mean age of 64 years (range, 20 to 85). There were thirteen patients (9.9%) who underwent concomitant total hip arthroplasty (THA). Of the included patients, 29% (n = 38) were categorized into group A, 12% (n = 16) into group B, and 59% (n = 77) into group C. Patients who had L4 to S1 pathology were older than patients who did not have L4 to S1 pathology (67 versus 61 years, P = .004). Of the patients undergoing concomitant THA and hip abductor repair, 54% demonstrated evidence of lumbo-sacral spine pathology.

CONCLUSIONS

Over 40% of patients undergoing isolated hip abductor tendon repair and >50% of patients undergoing concomitant hip abductor tendon repair and THA demonstrated evidence of L4 to S1 disease perioperatively. Patients demonstrating symptomatic hip abductor deficiency should be screened for concomitant lower lumbo-sacral spine pathology.

Exercise compared to a control condition or other conservative treatment options in patients with Greater Trochanteric Pain Syndrome: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

To estimate the effectiveness of exercise at end of treatment and long-term follow-up compared to a control condition or other conservative treatments in patients with Greater Trochanteric Pain Syndrome (GTPS).

METHODS

Databases were searched September 2021 and updated September 2023. Randomized controlled trials (RCT) comparing exercise interventions for patients with GTPS, to a control condition; corticosteroid injection; shock wave therapy; or other types of exercise programs were included. Risk of bias was assessed using the ROB2 tool. Meta-analyses were performed using a random-effects model. The certainty of the evidence was rated by the GRADE approach.

RESULTS

Six RCTs including a total of 733 patients with GTPS were included. Three trials compared exercise to sham exercise or wait-and-see control groups, two trials compared exercise to corticosteroid injection, two trials compared exercise to shockwave therapy, and one trial compared exercise to another type of exercise. Meta-analyses showed that in the long term, exercise slightly reduces hip pain and disease severity, while slightly improving patient-reported physical function and global rating of change compared to a control condition. No serious adverse events were reported. Compared to corticosteroid injection, exercise improves long-term global rating of change.

CONCLUSION

The current evidence supports a strong recommendation for exercise as first line treatment in patients clinically diagnosed with GTPS. Compared to corticosteroid injection, exercise is superior in increasing the likelihood that a patient experiences a meaningful global improvement. These results are based on few trials and a moderate number of patients.

REGISTRATION

This review was prospectively registered in the PROSPERO database of systematic reviews (ID: CRD42021261380). CONTRIBUTION OF PAPER.

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.

The Gluteus Medius Experiences Significant Excursion With Hip Flexion

Purpose

To evaluate the effect of hip flexion and rotation on excursion of the gluteus medius (Gmed) and minimus (Gmin) myotendinous unit.

Methods

Seven hips from 4 cadaveric specimens (males, 68.5 ± 18.3 years old) were dissected to isolate the Gmed posterior and lateral insertions and the Gmin proximal and distal insertions. Sutures were placed from tendon insertions through origins created in the iliac fossa to simulate the myotendinous unit. A load of 10N was applied. Myotendinous excursion was measured at 10° hip extension and 0°, 45°, and 90° of hip flexion in neutral rotation, and from maximum internal and external rotation in 90° flexion. The amount of abduction and rotation was also measured at each flexion position with 20N applied to each tendon. Repeated-measures analysis of variance with Tukey post hoc was used for statistics.

Results

Gmed-lateral excursion ranged from 2.4 ± 0.4 mm in 10° of hip extension to 23.0 ± 1.5 mm in 90° of flexion (P < .001), and Gmed-posterior excursion ranged from 0.92 ± 0.5 mm in 10° of extension to 38.1 ± 1.1 mm in 90° of flexion (P < .001). Gmin excursion shortened with hip flexion from 4.2 ± 0.3 mm in 10° of extension to -0.2 ± 1.5 mm in 90° of flexion (Gmin-prox: P = .525, Gmin-distal: P < .001). At 90° flexion from maximum internal to maximum external rotation, Gmin-distal and proximal demonstrated a 92.6% and 51.3% increase in excursion, respectively (P < .001). Gmed-lateral and Gmed-posterior demonstrated 49.4% and 23.1% increase in excursion with external rotation, respectively (P < .001).

Conclusions

The Gmed myotendinous unit undergoes significant excursion with hip flexion, whereas both Gmed and Gmin had significant excursion with femoral external rotation in 90° flexion.

Clinical Relevance

It is important to understand whether active or passive hip flexion or rotation in the early postoperative period causes excessive strain to an abductor tendon repair. We found that consideration should be given to limit flexion after Gmed repair and external rotation after Gmed or Gmin repairs.

Recreational activity after open hip abductor repair

BACKGROUND

Hip abductor tear (HAT) is an increasingly diagnosed cause of refractory lateral hip pain and dysfunction, affecting 10-25% of the general population.

PURPOSE

(1) to determine the rate of return to activity and to assess the physical and recreational activity of patients undergoing open hip abductor repair (oHATr) and (2) to describe the modification or initiation of new sports disciplines.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 28 patients (29 hips) who underwent an oHATr were prospectively analyzed at a midterm follow-up of 3.5 (range 2-5) years. The sports and recreational activity levels, as well as type of sports practiced before and after surgery, and The Veterans RAND 12 Item Health Survey (VR-12) were assessed via questionnaire.

RESULTS

At the final follow-up, all patients were active in sports after surgery. The duration and frequency of sports activities showed a slight decrease (48-42 min per week and 3.2-2.9 sessions per week, respectively) (p = 0.412 and 0.135, respectively). The VR-12 had a score of 45 (13.12-63.18) points for the physical component and 41 (32-53.8) points for the mental component. 100% of the patients would undergo the surgery again. 95% of patients were satisfied with the overall results of the surgical outcome, with 98% satisfied with their hip pain relief and ability to undertake daily and work activities. Moreover, 94% were satisfied with their ability to return to recreational activities. The failure rate in our cohort was approximately 14%.

CONCLUSION

All patients who underwent an oHATr were able to return at least to one type of sport. This cohort was highly satisfied with their sports involvement and recreational activity achievement. In addition, 88% of patients reported that oHATr improved sports activity. There was a shift from higher to lower impact sports. Furthermore, just 3 hips present a retear after surgery.

A Review of Abductor Tendon Tears: The Hidden Lesion of the Hip

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Greater trochanteric pain syndrome consists of a group of associated conditions involving the lateral hip that can be debilitating to patients, mostly women between ages 40 and 60 years.

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Abductor tendon tears are becoming a more recognized cause of lateral hip pain in patients without hip osteoarthritis.

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Diagnosis of this condition is critical to patient care because misdiagnosis often leads to unnecessary prolonged pain and even unnecessary procedures that address different pathologies.

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Treatment strategies consists of nonoperative modalities such as nonsteroidal anti-inflammatory medications, corticosteroid injections, and physical therapy, but for refractory cases, surgical techniques including repair, augmentation, and reconstruction have been well-described in the literature providing patients with acceptable outcomes.

Tendinopathies and Allied Disorders of the Hip

There are many soft tissue structures around the hip joint that may serve as a source of pain in both the native and prosthetic hip. In this review, the role of the gluteal, piriformis, iliopsoas, and rectus femoris musculotendinous units in the etiology of pathology around the hip joint will be discussed. Management options ranging from tailored physical therapy regimens to local steroid infiltration along with more invasive open and arthroscopic surgical techniques will be reviewed for each pathological entity. While not all conditions are well understood, advancements have been made in the management of each of these often challenging cases in both the native and prosthetic hip settings. This review explores these advancing treatment methods which will supplement the practice of any hip surgeon who is presented with problematic tendinopathy around both the native and prosthetic hip joint.

The relationship between gluteus medius and minimus muscle volumes and hip development in developmental dysplasia of the hip

BACKGROUND

Several studies in adult hips have revealed the role of the gluteus medius (Gmed) and gluteus minimus (Gmin) muscles in maintaining the stability and centripetal force of the hip joint. Hip centripetality in developmental dysplasia of the hip (DDH) patients contributes to subsequent healthy hip development later in life. The purpose of this study is to investigate the relationship between Gmed and Gmin volume and centripetality of the hip in infant DDH patients.

METHODS

We retrospectively enrolled 41 unilateral DDH patients (4 males, 37 females) who were treated by closed reduction from 2006 to 2016 and underwent magnetic resonance imaging at around 2 years old. Gmed, and Gmin volume was measured in magnetic resonance imaging. We defined both Gmin and Gmed together as hip abductor gluteus muscles (GMs; Gmed + Gmin). The muscle volume ratio of the affected side was calculated by dividing the GMs volume of the affected side by the contralateral side. Relationships between center-head distance discrepancy (CHDD) at 2 years old, and at 4-6 years old and GMs volume ratio were investigated by Pearson's correlation coefficient within the same patients.

RESULTS

Mean age of closed reduction was 0.8 years old and mean age at MRI was 2.2 years old with a mean follow-up period of 3.7 years. Mean GMs volume in the affected side, contralateral side, and muscle volume ratio were 25.3 cm³, 27.0 cm³, and 0.94, respectively. GMs volumes were significantly higher in the contralateral side (p < 0.001). GMs volume ratio at 2 years old significantly correlated with CHDD at 4-6 years old (p < 0.05).

CONCLUSION

GMs volume at 2 years old was found to be associated with later hip afferents. Promoting the healthy development of GMs by properly maintaining the infant's natural hip movement is important for the healthy hip development.

LEVEL OF EVIDENCE

Level III.

Repair of gluteus medius tears with bioinductive collagen patch augmentation: initial evaluation of safety and imaging

The purpose of this study was to perform an initial, prospective evaluation of imaging findings and outcomes after open surgical repair of gluteus medius tendon tears with bioinductive collagen patch augmentation. A prospective study was performed of patients with clinical and magnetic resonance imaging (MRI) evidence of symptomatic gluteus medius tears who underwent open, double-row suture anchor repair with bioinductive bovine collagen patch augmentation. Preoperative and 6-month postoperative MRIs were reviewed by a fellowship-trained musculoskeletal radiologist, and outcome scores were recorded preoperatively and 6 months postoperatively [Hip Outcome Score (HOS) Sport; HOS Activities of Daily Living (HOS ADL); Modified Harris Hip Score (mHHS) and International Hip Outcomes Tool (iHOT-33)]. Nine patients, four high-grade tears (≥50% tendon thickness) and five low-grade tears (<50% thickness) underwent surgical repair. At 6 months, 7/9 (77.8%) of tendons were qualitatively classified as completely healed on MRI, with no complications. Mean tendon thickness increased significantly: mediolateral dimension by 5.8 mm (P < 0.001), anteroposterior dimension by 4.1 mm (P = 0.02) and cross-sectional area (CSA) by 48.4 mm² (P = 0.001). Gluteus medius and minimus CSA did not change significantly (P > 0.05). Patients demonstrated improvements in mean scores for HOS ADL, mHHS and iHOT that met defined minimum clinically important differences (P < 0.05). Open surgical repair of gluteus medius tendon tears with bioinductive collagen patch augmentation is safe and associated with increased tendon thickness on postoperative MRI. Early outcome scores are encouraging and should be evaluated after patients have completed postoperative rehabilitation to measure the whole effect of treatment.

Surgical Treatment of Gluteus Medius Tears

The gluteus medius originates on the posterior face of the ilium between the posterior and anterior gluteal lines and inserts into the lateral and superoposterior facets of the greater trochanter. Because of the asymmetric nature of the muscle, tears are more likely to occur on the thinner anterolateral portion of the tendon footprint. Gluteus medius tears range from interstitial, partial thickness tears to retracted, full-thickness tears and may result from trauma, but they are more commonly the result of chronic degeneration. Patients commonly present with lateral hip pain aggravated by weight bearing and sleeping on the affected side, weakness in abduction, and the Trendelenburg sign observable on physical examination. Indications for surgery include failed conservative treatment and an ultrasound or magnetic resonance imaging study demonstrating a torn tendon. Surgical intervention aims to reapproximate and secure the torn tendon to the tendon footprint on the greater trochanter via suture anchors. Both open and endoscopic techniques have shown to be effective methods for treating gluteus medius tears at short- and long-term follow-up; however, endoscopic techniques have been shown to result in fewer postoperative complications, such as retear. A recent systematic review and meta-analysis found patients with more severe fatty infiltration (FI) may experience greater improvement after open repair, whereas patients with less severe FI may benefit more from endoscopic treatment. A double-row repair maximizes contact area between tendon and bone and has shown to be superior to single-row repair with an endoscopic technique.

High Prevalence of Lumbosacral Pathology in Patients with Greater Trochanteric Pain Syndrome

PURPOSE

To establish prevalence of lumbar and lumbosacral pathologies in patients with hip abductor tendon disorders.

METHODS

A retrospective review of patients' charts was conducted over a 5-year period, January 2013 to October 2018, using the S76 and M76 International Classification of Diseases Tenth Revision (ICD-10) codes. Patients with symptomatic and radiologically confirmed hip abductor tendon disorders (partial and full-thickness tear of the gluteus medius tear with or without gluteus minimus tearing) were included in the study. No exclusion criteria were applied. Patient medical history was examined for concurrent diagnoses of lumbar and lumbosacral pathologies (radiculopathy, lumbar stenosis, degenerative disc disease, and neurogenic claudication).

RESULTS

One-hundred and three patients with hip abductor tendon disorders were identified. Forty-seven (45.6%) patients had low-grade partial abductor tears, while 56 (54.4%) of patients had a high-grade partial or complete abductor tear. Fifty (48.5%) patients carried a concomitant lumbosacral diagnosis, with 20 (19.4%) patients being diagnosed with lumbar stenosis and 45 (43.7%) being diagnosed with degenerative disc disease.

CONCLUSION

Patients with hip abductor tendon disorders were associated with a high prevalence of underlying lumbar and lumbosacral pathologies. Nevertheless, a causal relationship between these conditions cannot be established.

LEVEL OF EVIDENCE

Level IV. Retrospective Case Series.

The Intergluteal Fat Stripe in Patients With Hip Abductor Tears

Background:

With a hip abductor tendon tear, widening of the intergluteal space, or “fat stripe,” is a characteristic change seen in and around the gluteus medius and minimus.

Purpose:

To determine the relationship of the intergluteal fat stripe in hips with pathologic abductor tears compared with the contralateral side and to evaluate the association of fat stripe size with hip-specific patient-reported outcome measures.

Study Design:

Case series; Level of evidence, 4.

Methods:

Of the 43 patients (42 female, 1 male; mean age, 56.6 years; range, 38-85 years) who underwent endoscopic gluteus medius repair, 19 met inclusion criteria of preoperative bilateral hip magnetic resonance imaging (MRI) scans and 2-year follow up. A single board-certified fellowship-trained orthopaedic surgeon (J.F.), who was blinded to outcomes, evaluated the MRI scans to measure the intergluteal fat stripe on the operative and nonoperative sides. The 2-year postoperative International Hip Outcome Tool (iHOT-12) and modified Harris Hip Score (mHHS) values were analyzed to determine their relationship to the size of the fat stripe. Statistical analysis was performed using a paired t test, and associations were determined using Pearson product correlation as well as nonparametric measurements.

Results:

The size of the intergluteal fat stripe differed significantly between the operative and nonoperative sides. The area of the fat stripe on the operative side was 645.73 ± 513.09 mm2, and on the nonoperative side it was 313.47 ± 360.71 mm2, an average of 332.36 mm2 greater than the nonoperative side ( P = .02). The width of the fat stripe was 9.10 ± 4.60 mm on the operative side and 5.15 ± 3.87 mm on the nonoperative side, 3.95 mm greater than the nonoperative side ( P < .01). There was no correlation between the width or area of the fat stripe on the operative side and iHOT-12 or mHHS values at 2-year follow-up.

Conclusion:

The study findings indicated that the intergluteal fat stripe is significantly wider and has a significantly larger area in hips with abductor tears compared with unaffected hips. This did not correlate with 2-year patient-reported outcomes.

Modelling gluteus medius tendon degeneration and repair in a large animal model

INTRODUCTION

Gluteus medius tendon tears often occur in the context of chronic tendinopathy and remain a difficult clinical problem. Surgical repair is challenging as it is often delayed and performed in degenerative tendons. No animal model currently exists to mimic the delayed repair of tendinopathic gluteus medius tears. The aims of this study were to develop a chronic model of gluteus medius tendinopathy and tear and then compare this model to an acute gluteus medius tear and repair.

MATERIALS AND METHODS

Six gluteus medius muscles were dissected and examined in mature sheep to confirm anatomical similarity to the human counterpart. Ten separate adult sheep underwent tendon detachment, followed by relook and histological sampling at 6 and 16 weeks to assess the extent of tendon degeneration. Six adult sheep underwent tendon repair at 6 weeks and were later assessed for healing of the tendon and compared to a further four adult sheep who underwent an acute tendon detachment and repair procedure.

RESULTS

The sheep gluteus medius muscle consisted of three compartments, the anterior, middle and posterior. All compartments inserted via the common tendon on the superolateral aspect of the greater trochanter. At both 6 and 16 weeks, there was significant tendinopathic changes on histology compared to controls as assessed by modified Movin's score (p = 0.018, p = 0.047) but no difference between the 6- and 16-week groups (p = 0.25). There were significant differences between delayed and acute repair in both histological appearance (p = 0.025) and biomechanical properties (p = 0.019), with acute repair superior in both.

CONCLUSIONS

Tendon detachment for 6 weeks is sufficient to produce histological changes similar to chronic tendinopathy and repair of this degenerative tendon results in significantly poorer healing when compared to an acute repair model. Animal models for gluteus medius tears should use a delayed repair model to improve clinical validity.

Open Hip Abductor Repair Hitting the Sack-Abductor Tendon Repair Significantly Improves Sleep Quality

PURPOSE

To (1) describe the prevalence of abnormal sleep quality in patients with hip abductor tears (HAT), to (2) determine whether sleep quality improves after open HAT repair, and to (3) to report clinical short-term outcomes in patients undergoing open HAT repair.

METHODS

The data of 28 patients (29 hips) who underwant open HAT repair were prospectively analyzed at midterm follow-up. The Pittsburgh Sleep Quality Index (PSQI), modified Harris Hip Score (mHHS), the University of California, Los Angeles activity scale (UCLA), and Visual Analog Scale (VAS) for pain were determined via questionnaire. Paired t-tests were applied to compare preoperative and post-operative Patient-reported Outcome Measures (PROMs). Logistic regression was performed to determine the association between PSQI improvement achievement and demographic variables (laterality, sex, age, body-mass-index (BMI), and preoperative mHHS). The minimal clinically important difference (MCID) was calculated for the mHHS.

RESULTS

A total of 28 patients were included. Four patients (14.3%) suffered post-operative complications after open HAT repair. The predominance of patients was female (77.4%), with a mean age of 60 ± 13 years. The average follow-up was 30.35 ± 16.62 months. Preoperatively, 27 (96.4%) patients experienced poor sleep quality (PSQI > 5); at follow-up, 7 (25%) patients experienced poor sleep quality. Univariate logistical regression analysis demonstrated no significant association between preoperative demographic data and achieving postoperative PSQI < 5. The MCID of mHHS was calculated to be 12.5. Overall, 90% of patients achieved MCID for mHHS.

CONCLUSION

Preoperative sleep quality was impaired in 96.4% of HAT patients (PSQI > 5). However, these patients showed an improvement in sleep disturbances after open HAT repair in the early postoperative period. Ninety percent of patients showed significant improvements in mHHS and achieved the corresponding MCID.

LEVEL OF EVIDENCE

Case series; Level IV.

Short-term outcomes following mini-open repair of chronic gluteus medius tendon tears using a double-row technique

Gluteal tendon tears represent a common but underreported cause of lateral hip pain and dysfunction. In case of conservative management failure, a surgical procedure must be performed to relieve patient symptoms. Current operative treatments, either open or endoscopic, have been however associated with different drawbacks which led to the introduction of the mini-open technique. The aim of this study was to evaluate and report the short-term outcomes of patients operated through the aforementioned surgical technique for gluteus medius (GM) chronic tears. We retrospectively analysed the records of 14 consecutive patients operated at the La Tour hospital by mini-open repair using a double-row technique for full-thickness GM chronic tears. Intra- and post-operative complications were recorded. The pre- and post-operative pain on visual analogue scale (pVAS), modified Harris Hip score (mHHS), abduction strength and gait dysfunction were assessed for all patients. Pre- and post-operative values were compared to evaluate whether improvements were statistically significant and clinically relevant. The study cohort comprised 13 women (93%) and 1 man (3%) aged 62.4 ± 18.0 at index surgery. No intra- or post-operative complications were noted. Compared to pre-operative values, patients reported a significant improvement in mHHS (59.1 ± 7.1 vs 92.7 ± 4.6) and pVAS (7.4 ± 1.0 vs 1.3 ± 1.3) at last follow-up. Patients exhibited a perfect improvement in muscle strength (3.6 ± 0.5 vs 5.0 ± 0.0), and the proportion of patients with a positive Trendelenburg sign decreased from 71% to 0%. Mini-open repair of chronic GM tendon tears using a double-row technique demonstrated excellent clinical and functional outcomes at short follow-up. Level of Evidence: IV.

[Avulsion injuries of the gluteus medius and gluteus minimus muscles]

Avulsion injuries of the gluteus medius and gluteus minimus muscles represent a diagnostic and therapeutic challenge. Such injuries are rarely to be expected in high-energy trauma. Degenerative damage or iatrogenic injuries in the context of hip surgery are more frequently identified as the cause. Clinically, in addition to lateral hip pain, limping is an important finding and depends on the extent of the tendon damage. In addition to the medical history and clinical examination, imaging by means of sonography and, above all, magnetic resonance imaging (MRI, possibly with artifact-reduced sequences in the presence of an endoprosthesis) are diagnostically groundbreaking. Therapeutically, a stepwise approach is indicated according to the extent of rupture and quality of the gluteal tendon and muscle tissues. Specific conservative training regimens, mini-open/endoscopic anatomic reconstruction techniques in cases of gluteal muscle integrity and muscle transfer techniques as salvage option with chronic mass ruptures are available. The common goal is the restoration of everyday occupational and private activities to regain the quality of life.

Defining Minimal Clinically Important Difference After Open Hip Abductor Repair

Background:

Open repair for gluteus medius and minimus tears is a common surgical treatment for patients with lateral hip pain associated with abductor tears; however, clinically meaningful outcomes have not been described after open surgical treatment.

Purpose:

To define the minimal clinically important difference (MCID) in patient-reported outcome measures (PROMs) in patients undergoing open gluteus medius or minimus repair, and to identify preoperative patient characteristics predictive of achieving MCID postoperatively.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective review of prospectively collected data from a consecutive series of patients undergoing open abductor repair between July 2010 and April 2019 was conducted. Perioperative patient data collected included patient characteristics and preoperative and postoperative modified Harris Hip Score (mHHS) and International Hip Outcome Tool (iHOT-33) score. Paired t tests were utilized to compare preoperative and postoperative PROMs and MCID was calculated for both PROMs. Multivariate logistical regression analysis was used to assess the association between preoperative variables and the likelihood for achieving MCID.

Results:

A total of 47 patients were included in the study. The majority of patients were female (78.7%), with an average age of 63 ± 10.7 years. The average follow-up for both the mHHS and the iHOT-33 surveys was 37.8 ± 27.9 months (range, 10-102 months). Patients demonstrated statistically significant improvements on the mHHS and iHOT-33 postoperatively (P < .001 for both). The MCIDs of mHHS and iHOT-33 were calculated to be 9.9 and 14.3, respectively. Overall, 82.9% of patients achieved MCID for mHHS and 84.1% of patients achieved MCID for iHOT-33 postoperatively. Multivariate logistical analysis demonstrated younger patients were less likely to achieve MCID for both outcome measures. Four patients (8.5%) suffered postoperative complications after open repair.

Conclusion:

This study defined MCID for mHHS and iHOT-33 for patients undergoing open repair of hip abductor tears, with a large percentage of patients (>80%) achieving meaningful outcomes for both outcome measures. There was a low complication rate. Younger patients were less likely to achieve MCID compared with older patients.

Pathogenesis and contemporary diagnoses for lateral hip pain: a scoping review

PURPOSE

Recent advances in diagnostic imaging techniques and soft tissue endoscopy now allow for precise diagnosis and management of extra-articular hip pathology. The aim of this scoping review is to present an evidence-based update of the relevant literature focussing only on the pathoanatomy, clinical assessment and the diagnosis of pathology in the peritrochanteric space.

METHODS

A literature search was performed on PubMed to include articles which reported on the anatomy and diagnosis of greater trochanteric pain syndrome, trochanteric bursitis, gluteus medius tears and external snapping hip syndrome.

RESULTS

A total of 542 studies were identified, of which 49 articles were included for full text analysis for the scoping review. Peritrochanteric space pathology can be broadly classified into (1) greater trochanteric pain syndrome (GTPS), (2) abductor tears and (3) external snapping hip syndrome. Anatomically, gluteus medius, gluteus minimus and tensor fascia lata work in conjunction to abduct and internally rotate the hip. The anterolateral part of the gluteus medius tendon is more prone to tears due to a thin tendinous portion. Increased acetabular anteversion has also been shown to be associated with gluteal and trochanteric bursitis. In terms of clinical examination, tests which were found to be most useful for assisting in the diagnoses of lateral hip pain were the single-leg stance, resisted external derotation of the hip, hip lag sign and the Trendelenburg's test. Dynamic ultrasound along with guided injections and MRI scan do assist in differentiating the pathology and confirming the diagnosis in patients presenting with lateral hip pain. Finally, the assessment of baseline psychological impairment is essential in this group of patients to ensure outcomes are optimised.

CONCLUSION

Lateral hip pain used to be a poorly defined entity, but advances in imaging and interest in sports medicine have led to a better understanding of the pathology, presentation and management of this cohort of patients. A thorough appreciation of the anatomy of the abductor musculature, specific clinical signs and imaging findings will lead to an appropriate diagnosis being made and management plan instituted.

LEVEL OF EVIDENCE

IV.

Relationship of the Pelvic-Trochanteric Index with greater trochanteric pain syndrome

OBJECTIVES

This study aimed to correlate a higher Pelvic-Trochanteric Index (PTI) with an increased varus of the femoral neck with greater trochanteric pain syndrome (GTPS). The secondary objective was to check whether the pelvic width changes with age.

METHODS

A prospective study was conducted to compare female patients diagnosed with GTPS (case group) with asymptomatic female participants (control group) from March 2011 to June 2017. On an anteroposterior pelvic radiograph, lines were drawn by two radiologists, and the PTI (ratio of the distance between the greater trochanters and distance between the iliac crests) was defined and the femoral neck-shaft angle was measured.

RESULTS

Data collected based on radiographs of 182 female patients (cases) and 150 female participants (controls) showed that the mean PTI was 1.09 (SD=0.01) in the case group and 1.07 (SD=0.01) in the control group (p<0.05), regardless of age. The distance between iliac crests increased with age (p<0.05) in symptomatic and asymptomatic individuals. It was also found that the mean femoral neck-shaft angle was 130.6° (SD=0.59) and progression of the varus angulation occurred with age in both groups, with a significance level of 5%.

CONCLUSIONS

The PTI was higher in patients with GTPS. The femoral neck-shaft angle does not differ between individuals with and without GTPS; however, it does decrease with age. The pelvic width tends to increase with aging in symptomatic or asymptomatic individuals; therefore, the increase in the pelvic width and decrease in the femoral neck-shaft angle can be interpreted as normal in aging women, which could alter the biomechanics of the hips and pelvis.

The pathological features of hip abductor tendon tears - a cadaveric study

Background

The hip abductors are crucial in maintaining pelvic stability. Tears in these tendons are common and often debilitating. There is uncertainty regarding both the histological and macroscopic features of hip abductor tears. This study aims to clarify both the macroscopic and microscopic features of the tendon and enthesis in hip abductor tendon tears.

Methods

Thirty-six cadavers with an average age of 81 were dissected, and the hip abductor mechanisms removed en-bloc. The presence, location and size of the tears were recorded and analysed. The samples were processed into histological blocks and viewed using both transmitted and polarised light. Tendon histology was graded using the modified Movin’s score in three sections (deep, middle and superficial layers) and the enthesis graded separately using 5-point criteria. Analysis of variance was used to confirm histological features associated with tears.

Results

Tears were found in 24 of 36 samples (67%). The most common finding was an isolated tear in the gluteus minimus (46%), followed by concurrent gluteus medius and gluteus minimus tears (33%). Histology revealed significantly more degeneration in both the tendon (p = 0.0005) and enthesis (p = 0.0011) when tears were present. Furthermore, these changes were concentrated in the deeper layers of the tendon (p = 0.0002) and enthesis (p = 0.003).

Conclusion

This study demonstrated degeneration as the primary pathology underlying hip abductor tendon tears. Degenerative changes occur in both the tendon and enthesis, with the deeper layers predominantly affected. These findings are important for guiding surgical repair techniques and to aid the development of novel materials and biologics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-020-03784-3.

Mid-Term Outcomes of Endoscopic Gluteus Medius Repair With Concomitant Arthroscopic Labral Treatment: A Propensity-Matched Controlled Study

PURPOSE

To report mid-term outcomes of patients who underwent endoscopic gluteus medius (GM) repair with arthroscopic labral treatment and to compare them with a control cohort of patients who underwent arthroscopic labral treatment without an endoscopic GM repair.

METHODS

Data were prospectively collected and retrospectively reviewed for all patients who underwent primary hip arthroscopy between February 2008 and August 2013. Patients were included if they underwent arthroscopic labral treatment, endoscopic GM repair, and had preoperative with minimum 5-year follow-up for the following patient-reported outcomes: modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), and Hip Outcome Score-Sports Specific Subscale (HOS-SSS). Propensity score matching was used to create a control cohort of patients who underwent primary arthroscopic labral treatment without GM repair.

RESULTS

There were a total of 46 patients with GM repair eligible for the current study, of whom 43 (93.5%) had 5-year follow-up. The average follow-up time was 73.4 months. At minimum 5-year follow-up, all PROs significantly improved (P < .001). Among the entire GM repair cohort, rates for achieving the patient acceptable symptomatic state (PASS) for mHHS, HOS-SSS, and international Hip Outcome Tool (iHOT-12) were 74.4%, 51.9%, and 71.8%, respectively. Rates for reaching a minimal clinically important difference for mHHS, NAHS, and HOS-SSS were 79.5%, 89.7%, and 73.1%, respectively. When the GM repair cohort was matched, there were 37 cases in the GM repair cohort and 78 in the control cohort. The GM repair cohort outcomes compared satisfactorily to the control cohort for mHHS (82.3 vs 82.6), NAHS (81.9 vs 82.3), and HOS-SSS (66.3 vs 67.5). Rates of achieving minimal clinically important difference and PASS for mHHS, NAHS, HOS-SSS, and iHOT-12 were also favorable.

CONCLUSIONS

Endoscopic GM repair with arthroscopic labral treatment results in safe, durable, and significant improvement in PROs at a minimum 5-year follow-up. The outcomes compared favorably with a control cohort without GM tears.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Clinical Outcomes After Endoscopic Repair of Gluteus Medius Tendon Tear Using a Knotless Technique With a 2-Year Minimum Follow-Up

PURPOSE

To evaluate clinical outcomes in patients who underwent endoscopic gluteus medius repair with at least 2-year follow-up.

METHODS

This was a single-center, single-surgeon retrospective study of 19 patients (20 hips) who underwent endoscopic knotless gluteus medius repair between August 2010 and August 2016 with ≥2 years of follow-up. Preoperative magnetic resonance imaging (MRI) was reviewed and graded according to the Goutallier/Fuchs classification; preoperative X-rays were reviewed and graded according to the Tonnis classification. Baseline and 2-year postoperative modified Harris hip score (mHHS) and nonarthritic hip score (NAHS) were prospectively collected. The numbers of patients reaching the minimal clinically important difference (MCID) and patient acceptable symptomatic rate (PASS) were determined.

RESULTS

Twenty hips from 19 patients met the inclusion criteria and were separated based on tear type. The study population comprised 15 (79%) females and 4 (21%) males presenting with a mean age of 51.3 ± 11.9 years and an average body mass index of 25.3 ± 3.9 kg/m². Patients with partial tears reported average preoperative mHHS and NAHS of 33.6 ± 11.3 and 40.4 ± 14.9, respectively; at 2-year follow-up, average mHHS and NAHS of 72.9 ± 22.9 and 77.2 ± 19.7 were reported. Patients with full-thickness tears reported average preoperative mHHS and NAHS of 43.8 ± 14.7 and 46.4 ± 8.3, respectively; at 2-year follow-up, average mHHS and NAHS of 80.1 ± 8.5 and 79.5 ± 10.1 were reported. There was significant clinical improvement at 2-year follow-up, relating to both outcome measures in each subject group (P < .001). At 2 years, 90% of hips surpassed MCID, and 63% of hips achieved PASS.

CONCLUSION

Endoscopic repair for gluteus medius tears results in improved mHHS and NAHS at 2 years of follow-up compared with baseline. Most patients reach critical thresholds of minimal and satisfactory clinical improvement.

LEVEL OF EVIDENCE

Level IV, case series with subgroup analysis.

Prevalence of Gluteus Medius Pathology on Magnetic Resonance Imaging in Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement: Asymptomatic Tears Are Rare, Whereas Tendinosis Is Common

BACKGROUND

There is a paucity of literature on asymptomatic gluteus medius pathology. Moreover, no studies have examined the prevalence of asymptomatic gluteus medius pathology.

PURPOSE

To describe the prevalence of asymptomatic gluteus medius pathology in patients undergoing hip arthroscopy for femoroacetabular impingement.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A database search of our institution was performed for patients undergoing hip arthroscopy for labral treatment between February 2008 and January 2019. Patients were included if they had gluteus medius pathology identified through magnetic resonance imaging (MRI). Patients were deemed to be asymptomatic if they lacked greater trochanteric hip tenderness, abductor weakness, a positive Trendelenburg sign, or a positive Trendelenburg gait on physical examination. Patients were excluded if they were unwilling to participate or did not have a documented physical examination or MRI read in the database.

RESULTS

A total of 2851 hips (2452 patients) met the inclusion/exclusion criteria. Gluteus medius pathology was found in 871 hips (30.6%) on MRI. Symptomatic gluteus medius pathology was observed in 414 (14.5%) hips, of which 305 (10.7%) had tendinosis, 99 (3.5%) had partial-thickness tears, and 10 (0.4%) had full-thickness tears. Asymptomatic gluteus medius pathology was observed in 457 (16.0%) hips, of which 408 (14.3%) had tendinosis and 49 (1.7%) had partial-thickness tears. No hips with full-thickness tears on MRI were asymptomatic. Patients with asymptomatic partial-thickness tears were significantly older than those with only tendinosis (45.3 vs 39.4 years, respectively; P = .001). Patients aged 40 years or older had a 2.11 (1.80-2.50) (P < .001) relative risk of asymptomatic pathology compared with patients younger than 40 years.

CONCLUSION

Although there is a meaningful prevalence of asymptomatic gluteus medius tendinosis, the prevalence of asymptomatic gluteus medius tears is low. Treatment of gluteus medius tendinosis should therefore be based not solely on MRI findings but rather on a complete clinical evaluation. In contrast, MRI findings of partial or full-thickness gluteus medius tears may be more likely to have clinical significance.

Lesions of the abductors in the hip

Abductor tendon lesions and insertional tendinopathy are the most common causes of lateral thigh pain. Gluteal tendon pathology is more prevalent in women and frequency increases with age.

Chronic atraumatic tears result in altered lower limb biomechanics. The chief complaint is lateral thigh pain. Clinical examination should include evaluation of muscle strength, lumbar spine, hip and fascia lata pathology. The hip lag sign and 30-second single leg stance tests are useful in diagnosing abductor insufficiency.

Magnetic resonance imaging (MRI) is the gold-standard investigation to identify abductor tendon tears and evaluate the extent of muscle fatty infiltration that has predictive value on the outcome of abductor repair.

Abductor tendinosis treatment is mainly conservative, including non-steroidal anti-inflammatory medications, activity modification, local corticosteroid injections, plasma-rich protein, physical and radial shockwave therapy. The limited number of available high-quality studies on treatment outcomes and limited evidence between tendinosis and partial ruptures make it difficult to provide definite conclusions regarding the best management of gluteal tendinopathy.

Surgical management is indicated in complete and partial gluteal tendon tears that are unresponsive to conservative treatment.

There are various open and arthroscopic surgical procedures for direct repair of abductor tendon tears. There is limited evidence concerning surgical management outcomes. Prerequisites for effective tendon suturing are neurologic integrity and limited muscle fatty infiltration. Chronic irreparable tears with limited muscle atrophy and limited fatty infiltration can be augmented with grafts. Gluteus maximus or/vastus lateralis muscle transfers are salvage reconstruction procedures for the management of chronic end-stage abductor tears with significant tendon insufficiency or gluteal atrophy.

Cite this article: EFORT Open Rev 2020;5:464-476. DOI: 10.1302/2058-5241.5.190094

Hip abductor tendon tears: where are we now?

Hip abductor tendon tear is a difficult problem to manage. The hip abductor mechanism is made up of the gluteus medius and minimus muscles, both of which contribute to stabilising the pelvis through the gait cycle. Tears of these tendons are likely due to iatrogenic injury during arthroplasty and chronic degenerative tendinopathy. Ultrasound and magnetic resonance imaging have provided limited clues regarding the pattern of disease and further work is required to clarify both the macro and microscopic pattern of disease. While surgery has been attempted over the last 2 decades, the outcomes are variable and the lack of high-quality studies have limited the uptake of surgical repair. Hip abductor tendon tears share many features with rotator cuff tears, hence, innovations in surgical techniques, materials and biologics may apply to both pathologies.

Bare area on the trochanter and its correlations to gluteal tendon insertion dimensions

Gluteus medius and minimus tears have recently been reported to be very common and the main etiology of lateral sided hip pain. The purpose of this study was to determine whether there is any correlation between the dimensions of the tendon insertions and bare areas (BA) and various bony landmarks. Twenty-seven hemipelvises from adult male hips were included. The bony landmarks [anterior tip (Ta), posterior tip of trochanter, vastus tubercle (VT) and center of BA] were marked. The longitudinal lengths and widths (maximum) of posterosuperior (PS), lateral facets (LF), minimus insertion (Min) and BA and the distance between posterior (Tp) and Ta and between anterior/posterior tips and the VT or center of BA were measured using a digital caliper. A correlation analysis was performed between variables. There was a correlation between LF_length and Min_length (r = 0.4, P = 0.01) and between Ta-BA and PS + LF (r = 0.5, P = 0.003) or Min_length (r = 0.4, P = 0.016). LF_width was negatively correlated with BA_width (r = -0.4, P = 0.002). Tp-BA was negatively correlated with BA_width (r = -0.4, P = 0.01). LF_width was correlated with Tp-BA, and this nearly reached statistical significance (r = 0.3, P = 0.05). BA can be used intraoperatively as landmarks to estimate the width of the LF and also to determine the length of the longitudinal insertion of the gluteus medius and minimus tendons.

Gluteus medius muscle pathologies - A case series & pictorial review

Introduction

Gluteus medius lesions are rare and can present with lateral hip pain. We present a spectrum of pathologies involving the gluteus medius and discuss the imaging features.

Material and methods

A search of our oncology database at tertiary orthopaedic oncology service was performed. The imaging features of these were analysed.

Results

There were nine cases involving the gluteus medius, which included soft tissue sarcomas, lipomas, infection and trauma with an average age of 62 years.

Conclusion

Gluteus medius lesions are rare and one should be aware of these as these can present as lateral hip pain.

Acute Traumatic Tear of the Gluteus Medius and Gluteus Minimus in a Marathon Runner

Background: Tears of the gluteus medius and gluteus minimus are common causes of chronic lateral hip pain in the middle-aged population. These tears are postulated to occur after chronic degeneration of the muscle-tendon unit. The majority of these patients have a long history of peritrochanteric pain. Acute traumatic tear of the gluteus medius and gluteus minimus in otherwise asymptomatic patients is rare but can occur.

Case Report: We report the case of a 78-year-old male marathon runner with acute traumatic tear of the gluteus medius and gluteus minimus. After conservative management (physical therapy, a nonsteroidal antiinflammatory drug for pain, and cortico-steroid and local anesthetic injection) failed, the patient underwent operative repair. The surgery was successful, and the patient returned to his preinjury lifestyle 6 months postoperatively with no limitations.

Conclusion: In most cases, chronic injuries are far more common than acute tears. Because of the nonspecific and slowly progressive symptoms, patients are often misdiagnosed with radiculopathy, osteoarthritis, or trochanteric bursitis. Patients typically present to the clinic with an insidious onset of dull pain over the lateral hip. This pain is often worse when lying on the affected side. Certain gluteal-focused movements, such as climbing stairs, may exacerbate the pain. To our knowledge, our report is only the third case of acute traumatic tear of the gluteus medius and gluteus minimus reported in the literature.

Diagnostic accuracy of a new clinical test (resisted internal rotation) for detection of gluteus medius tears

The objective of this study was to evaluate the diagnostic accuracy of a new dynamic clinical examination for detection of gluteus medius (GM) tears. A case group of 50 patients undergoing arthroscopy with GM repair was compared with a control group of 50 patients undergoing arthroscopy who had no peritrochanteric symptoms. Both groups were examined clinically, had magnetic resonance imaging studies performed and underwent arthroscopic surgery. Recorded clinical examinations included abnormal gait (Trendelenburg), tenderness to palpation of the greater trochanter, resisted abduction and the test being studied, resisted internal rotation. For all clinical tests, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy rates were calculated and compared with the arthroscopic and MRI data for the case group, and the MRI data for the control group. The resisted internal rotation test had a sensitivity of 92%, specificity of 85% and diagnostic accuracy of 88% in the detection of GM tears, with a low rate of false-positive and false-negative recordings. Other traditional clinical examination tests, with the exception of Trendelenburg gait, showed inferior rates. Trendelenburg gait had a higher specificity, but much lower sensitivity. The resisted internal rotation test aides in the detection of GM pathology. Due to the good results of the resisted internal rotation test in all the diagnostic parameters, we recommend incorporating it on the physical exam of patients with hip pain.

Superior Gluteal Reconstruction for Severe Hip Abductor Deficiency

Abductor tendon tears are one of the common causes of recalcitrant laterally based hip pain and dysfunction. In most cases, abductor tendon tears are associated with chronic nontraumatic tearing of the gluteus medius tendon. Restoring abductor function of the hip by primary repair of the gluteus medius tendon has been reported to have good and excellent outcomes. However, primary repair might not be as effective for chronic detachment of the gluteus medius tendon with a wide separation from the femoral footprint or severe tendon loss. The lack of tendinous foot for repair and the intrinsically degenerative condition of the tendon may create high tension at the repair site thereby predisposing to surgical failure. We believe that the use of soft-tissue allograft from the Achilles tendon or human dermal allograft may help strengthen the surgical site. We describe a superior gluteal reconstruction technique that is suitable for cases with abductor tendon tear with severe tendon loss.

[Surgical repair of gluteus medius muscle in hip replacement surgery]

Injury of gluteus medius muscle is a serious often complication after hip replacement surgery followed by pain, claudication and significant deterioration of the quality of life. Prevention of intraoperative injury of this muscle is especially relevant in young patients. Normal function of this muscle provides rapid rehabilitation and early postoperative recovery. However, hip replacement surgery through Hardinge's direct lateral approach is accompanied by fatty degeneration of gluteus medius muscle in 12-20% of cases. Moreover, two or more redo procedures lead to fatty degeneration of almost 70% of anterior and 40% of central muscular segment. Currently, there are many methods of surgical treatment of this complication including transosseous muscle fixation, endoscopic procedures, repair using Achilles tendon, gluteus maximus muscle, lateral head of quadriceps muscle and allografts. However, various publications devoted to this problem have certain disadvantages including short follow-up period, small sample size and often unsatisfactory outcomes. Therefore, the question of surgical repair of hip abductor function remains open.

Editorial Commentary: Single Versus Double-Row Abductor Tendon Repair: Is the Juice Worth the Squeeze?

Anatomical understanding of the peritrochanteric space and abductor insertions has been well documented in the literature. Extrapolating this knowledge to perform a "successful" abductor tendon repair has led to controversy over the best method to achieve a durable, stable repair and improve patient outcomes. I feel that the debate in the hip over single- versus double-row fixation is only beginning and we are in for a ride to uncover the best method, as we have with the shoulder over the last 15 years. What is best? Single or double row?

Single- Versus Double-Row Repair of Hip Abductor Tears: A Biomechanical Matched Cadaver Study

PURPOSE

The purposes of this study were (1) to evaluate the percentage of gluteus medius and minimus tendon footprint restoration that can be achieved with fixation using single-row repair versus double-row repair and (2) to evaluate the yield load of a repair of the gluteus medius and minimus tendon using single-row versus double-row repair techniques.

METHODS

Twelve human fresh-frozen cadaveric hip specimens (6 matched pairs, 4 female, mean age 47.5 ± 14.5 years) were tested. Specimens were excluded if they had any prior hip surgery or injury, if any abnormality of the tendon was noted on dissection, or if they had a body mass index <20 or >35 or a T-score <2.0 on dual-energy x-ray absorptiometry scanning. Matched pairs were randomized to receive either double-row repair with 2 standard suture anchors and 2 knotless anchor devices or a single-row repair with suture anchors only. The percentage of the footprint area covered after repair was determined using a computer-assisted digitization algorithm. With a mechanical testing system, each repaired specimen was tested for mechanical strength first with cyclic loading and then load to failure testing.

RESULTS

Footprint coverage of the lateral facet was significantly greater for double-row repair (mean 76.6%) compared with single-row repair (mean 50.3%) (P = .03). There was no significant difference between single- and double-row repair for posterior-superior or anterior facet coverage. Mechanical testing showed a higher mean yield load for double-row anchor repair (197.6 ± 61.7 N vs 163.5 ± 35.4 N for single-row repair), but this did not reach statistical significance (P = .15). The predominant mode of failure was suture pullout through the musculotendinous unit (9/12 specimens: 5 double-row and 4 single-row).

CONCLUSIONS

For hip abductor tears, double-row suture repair yields improved footprint coverage compared with single-row repair. Although it did not reach statistical significance, there was a higher mean yield load in the double-row group.

CLINICAL RELEVANCE

Double-row suture fixation technique for hip abductor tears maximizes strength and footprint coverage of the repair.

The Modified Resisted Internal Rotation Test for Detection of Gluteal Tendon Tears

Greater trochanteric pain syndrome (GTPS) has received increasing attention in recent years. Most patients with GTPS present with trochanteric bursitis and respond to nonoperative treatment. However, a subset of patients may have persistent lateral hip pain or recalcitrant GTPS resulting from an undiagnosed gluteal tendon tear. Recalcitrant GTPS may be a debilitating condition in this patient subset. There is a need for an accurate and evidence-based physical examination maneuver to aid in earlier diagnosis of gluteal tendon tears and timely intervention in these patients. Most studies evaluating gluteal tendinopathy fail to assess surgical indications and instead focus on identifying trochanteric bursitis, which may or may not require surgical treatment. The modified resisted internal rotation test has been used in our practice to detect gluteus medius tendon tears in the recalcitrant GTPS patient population. Fundamental anatomic, biomechanical, electromyographic, and clinical data have been reviewed to make this an evidence-based clinical test for early detection of this pathology.

Gluteus medius tears of the hip: a comprehensive approach

Greater trochanteric pain syndrome (GTPS) is a common clinical condition that can affect a wide range of patients. Historically, the condition has been associated with trochanteric bursitis. More recently, however, a growing body of literature has demonstrated gluteus medius tendinopathy and tearing is present in many cases of GTPS. Pathology of the gluteus medius can result in significant hip pain, loss of motion, and decreased function. Affected patients characteristically have symptoms including lateral hip pain and a Trendelenburg gait, which may be refractory to conservative management such as non-steroidal anti-inflammatory drugs (NSAIDs), physical therapy, and injections. In these cases, both open and arthroscopic repair techniques have been described, with recent literature demonstrating excellent patient-reported outcomes. We present a comprehensive review of gluteus medius tears including relevant anatomy, clinical evaluation, diagnosis, and treatment options.

The Gluteus Medius Tendon and Its Insertion Sites: An Anatomical Study with Possible Implications for Gluteus Medius Tears

BACKGROUND

Gluteus medius tears are a common hip disorder. Despite this, the etiology of these tears and the anatomical background of the gluteus medius tendon remain unclear. This study aimed to clarify the characteristics of the gluteus medius tendon. We hypothesized that the tendinous portions of the gluteus medius have a nonuniform structure contributing to the tear etiology.

METHODS

Twenty-five hips from 15 Japanese cadavers were analyzed. Twenty-one of the hips were analyzed macroscopically, and the other 4 were analyzed histologically. In all of the specimens, the 3-dimensional (3D) morphology of the greater trochanter was examined using microcomputed tomography (micro-CT). In 10 of the 21 hips analyzed macroscopically, the local thickness of the gluteus medius tendon, detached from the greater trochanter, was measured.

RESULTS

The posterior and anterolateral parts of the gluteus medius tendons were roughly distinguished on the basis of the aspects of the iliac origins. The posterior part of the gluteus medius tendon ran in a fan-like shape and converged onto the superoposterior facet of the greater trochanter. The anterolateral part ran posteroinferiorly toward the lateral facet of the greater trochanter. The thickness was greater in the posterior part than in the anterolateral part, and the border between these 2 parts was relatively thin compared with the other parts. The histological study showed that both the posterior and anterolateral parts inserted onto the greater trochanter via fibrocartilage.

CONCLUSIONS

The gluteus medius tendon consists of thick posterior and thin anterolateral parts, which were identified by the facet or aspect of the bone structures and thinness of their border region.

CLINICAL RELEVANCE

Our findings indicate that, given the nonuniform structure of the gluteus medius tendon, the thin anterolateral part may be more prone to tears than the thick posterior part is and tears may generally be limited to the anterolateral part.

Focused extracorporeal shock wave therapy for greater trochanteric pain syndrome with gluteal tendinopathy: a randomized controlled trial

OBJECTIVES:

To investigate if focused extracorporeal shock wave therapy (f-ESWT) is an effective treatment in a population affected by greater trochanteric pain syndrome (GTPS).

DESIGN:

Randomized controlled trial, with blind outcome assessors.

SETTING:

Outpatients, University Hospital.

SUBJECTS:

A total of 50 patients affected by GTPS with gluteal tendinopathy.

INTERVENTIONS:

The study group was assigned to receive f-ESWT, the control group received ultrasound therapy (UST).

MAIN MEASURES:

We assessed hip pain and lower limb function by means of a numeric rating scale (p-NRS) and the Lower Extremity Functional Scale (LEFS scale), respectively. The first follow-up evaluation (2M-FUP) was performed two months after the first treatment session, the second (6M-FUP) was carried out six months later.

RESULTS:

The mean age of the population was 61.24 (9.26) years. A marked prevalence of the female sex was recorded (44 subjects, 86%). The statistical analysis showed a significant pain reduction over time for the study group and the control group, the f-ESWT proving to be significantly more effective than UST ( P < 0.05) at the 2M-FUP (2.08 vs 3.36) and at the 6M-FUP (0.79 vs 2.03). A marked improvement of the LEFS total score was observed in both groups as well, but we found no statistical differences in the comparisons between groups.

CONCLUSION:

Our findings support the hypothesis that f-ESWT is effective in reducing pain, both in the short-term and in the mid-term perspective. We also observed a functional improvement in the affected lower limb, but, in this case, f-ESWT showed not to be superior to UST.

Knotless "Suture Staple" Technique for Endoscopic Partial Thickness Abductor Tendon Repair

Transtendinous abductor tendon repair is a technique the authors described previously to diagnose and treat undersurface tears of the abductor tendons. In this surgical technique article, the authors describe a technique for knotless repair of undersurface tears of the abductor tendons that does not require a transtendinous split or suture passage through the abductor tendon. Because there is no suture passage through the abductor tendon or knot tying, the potential advantages include expeditious technique, compression of tendon against bony footprint, anatomic repair, and avoidance of knots facing the undersurface of the iliotibial band, which may lead to bursal irritation.

Endoscopic Repair of Partial-Thickness Undersurface Tears of the Abductor Tendon: Clinical Outcomes With Minimum 2-Year Follow-up

PURPOSE

To report the minimum 2-year outcomes of transtendinous repair of partial-thickness undersurface tears of the abductor tendon using patient-reported outcomes (PROs), visual analog scale (VAS) scores, and patient satisfaction scores.

METHODS

All patients who underwent endoscopic transtendinous gluteus medius repair between October 2009 and May 2013 at 1 institution were prospectively evaluated. The exclusion criteria consisted of less than 2 years' follow-up, previous hip surgery, inflammatory arthritis, open surgery, full-thickness abductor tear, and Workers' Compensation patients. All patients underwent a documented preoperative physical examination with strength testing (scale of 0-5) and observation of their gait. Patient satisfaction and PRO scores were recorded preoperatively; at 3 months postoperatively; and at 1, 2, 5, and 10 years after surgery. The PRO scores collected were the modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living Subscale, Hip Outcome Score-Sports-Specific Subscale, Non-arthritis Hip Score, and VAS score. Preoperative strength and gait were compared with latest follow-up.

RESULTS

There were 25 patients who fit our criteria. Significant improvement in PRO scores were shown for the modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living Subscale, Hip Outcome Score-Sports-Specific Subscale, Non-arthritis Hip Score, and VAS score from 54.9 to 76.2, from 50.2 to 80.6, from 30.1 to 67.3, from 51.9 to 82.4, and from 7.1 to 2.7, respectively (P < .001). Before surgery, 11 patients had objective weakness; 7 of these patients moved up at least 1 strength grade by final follow-up. Preoperatively, 14 patients had a Trendelenburg gait; 12 of them had a normal gait at latest follow-up (P < .001). The average patient satisfaction rating was 7.5. There were no revision surgical procedures, and no complications were noted.

CONCLUSIONS

Partial-thickness undersurface tears of the abductor can be treated successfully with endoscopic transtendinous repair preserving the intact attachment of the superficial fibers of the gluteus medius. We recommend this treatment for partial undersurface tears recalcitrant to nonoperative treatment because patients showed clinical benefit at greater than 2 years' follow-up that exceeded substantial clinical benefit and the minimal clinically important difference.

LEVEL OF EVIDENCE

Level IV, case series.

Ultrasound Diagnostic and Therapeutic Injections of the Hip and Groin

Hip and groin pain often presents a diagnostic and therapeutic challenge. The differential diagnosis is extensive, comprising intra-articular and extra-articular pathology and referred pain from lumbar spine, knee and elsewhere in the pelvis. Various ultrasound-guided techniques have been described in the hip and groin region for diagnostic and therapeutic purposes. Ultrasound has many advantages over other imaging modalities, including portability, lack of ionising radiation and real-time visualisation of soft tissues and neurovascular structures. Many studies have demonstrated the safety, accuracy and efficacy of ultrasound-guided techniques, although there is lack of standardisation regarding the injectates used and long-term benefit remains uncertain.

Acute Isolated Tear of Gluteus Medius in Young Male

The hip rotator cuff tear usually develops in the middle-aged through gradual degenerative changes, similar to rotator cuff tears in the shoulder. An acute tear in the hip abductor by a traumatic event in young ages is very uncommon. The authors experienced an unusual case of an acute traumatic tear isolated to the gluteus medius in a young male; thus, we report the treatment results in this rare case with a review of the literature.

Endoscopic Gluteus Medius Repair With Concomitant Arthroscopy for Labral Tears: A Case Series With Minimum 5-Year Outcomes

PURPOSE

To report the minimum 5-year outcomes of endoscopic gluteus medius repair for partial- and full-thickness tears with concomitant hip arthroscopy.

METHODS

Data for all patients who underwent hip arthroscopy between February 2009 and September 2011 were prospectively collected. We included patients who underwent endoscopic gluteus medius repair with concomitant arthroscopic labral treatment and for whom the following measures were obtained preoperatively and at a minimum of 5 years' follow-up: modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, and visual analog scale score for pain. For included patients, the International Hip Outcome Tool-12 (iHOT-12) score and satisfaction rating were also available at latest follow-up. Patients with at least 1 of the following criteria were excluded: preoperative Tönnis osteoarthritis grade of 2 or greater, previous hip conditions, severe dysplasia, and Workers' Compensation claims.

RESULTS

There were 16 patients eligible for inclusion, 14 (87.5%) of whom had minimum 5-year follow-up, with a mean of 68.8 months (range, 60.1-79.6 months). The study group consisted of 13 women (92.9%) and 1 man (7.1%) with a mean age at surgery of 57.4 years (range, 46.3-74.8 years). Outcome scores improved as follows: modified Harris Hip Score, from 52.4 to 81.2 (P = .004); Non-Arthritic Hip Score, from 48.0 to 82.5 (P = .002); Hip Outcome Score-Sports Specific Subscale, from 30.1 to 66.4 (P < .001); and visual analog scale score, from 6.2 to 2.6 (P = .001). At minimum 5-year follow-up, the mean iHOT-12 score was 73.8 and the mean patient satisfaction rating was 8.4. Survivorship was 92.9%, with 1 patient who underwent conversion to total hip arthroplasty. There was no deterioration in patient outcomes and satisfaction between 2 and 5 years postoperatively. There were no clinical failures of gluteus medius repair and no complications.

CONCLUSIONS

Endoscopic gluteus medius repair with concomitant hip arthroscopy for labral tears is safe and shows favorable outcomes at minimum 5-year follow-up. Patient outcomes were as favorable at 5 years as they were at 2 years postoperatively.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Relationship Between Age at Onset of Symptoms and Intraoperative Findings in Hip Arthroscopic Surgery

Background:

Hip arthroscopic surgery is intended to treat multiple abnormalities in an effort to delay the progression to osteoarthritis, especially in young patients. However, the length of time in which patients experience joint pain before seeking a specialist for a diagnosis can delay hip preservation surgery and influence clinical outcomes.

Purpose:

To investigate the relationship between age at symptom onset and findings during hip arthroscopic surgery as well as outcomes after 2 years of clinical follow-up.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

From February 2008 to March 2015, data were prospectively collected on all patients undergoing hip arthroscopic surgery at a single institution. Anatomic and pathological characteristics were recorded intraoperatively. The mean age at onset of symptoms was calculated and correlated with intraoperative findings using Pearson correlation and logistic regression. All patients were assessed preoperatively and postoperatively with 4 patient-reported outcome measures: the modified Harris Hip Score (mHHS), the Non-Arthritic Hip Score (NAHS), the Hip Outcome Score–Activities of Daily Living (HOS-ADL), and the Hip Outcome Score–Sport-Specific Subscale (HOS-SSS). Pain was estimated using a visual analog scale (VAS). Furthermore, patients with an age at onset of symptoms below the mean (34.6 years) were compared with those of an age at onset of symptoms above the mean. The 2 groups were compared using the Student t test and the chi-square test. P values <.05 were considered significant.

Results:

A total of 1697 patients met the inclusion criteria. Body mass index was weakly correlated with age (r = 0.3). Younger patients had a lower prevalence of combined Seldes type 1 and 2 labral tears; acetabular labrum articular disruption (ALAD) grade 2, 3, and 4 acetabular chondral lesions; and Outerbridge grade 2, 3, and 4 femoral head chondral lesions (P < .05 for all). More advanced age was correlated with wider labral tears and chondral lesions based on a clock face (r ≥ 0.2, P < .05). Patients younger than 34.6 years had a lower prevalence of gluteus medius and ligamentum teres tears (P ≤ .001). The prevalence of synovitis was positively correlated with age, while instability was negatively correlated with age (P = .04). The improvement of scores from preoperatively to 2-year follow-up in the younger patient group was 62.69 to 83.82 for the mHHS, 64.97 to 87.35 for the HOS-ADL, 43.46 to 73.37 for the HOS-SSS, 63.01 to 85.19 for the NAHS, and 5.61 to 2.53 for pain VAS. All score improvements were statistically significant (P < .001). Regarding the older patient group, the improvement of scores from preoperatively to 2-year follow-up was 58.55 to 78.27 for the mHHS, 57.59 to 79.66 for the HOS-ADL, 35.63 to 61.88 for the HOS-SSS, 55.28 to 77.55 for the NAHS, and 5.72 to 3.01 for pain VAS. All score improvements were statistically significant (P < .001).

Conclusion:

Of the multiple intraoperative findings in hip arthroscopic surgery, many are related to age at onset of symptoms. Although we found a statistically significant improvement in clinical outcomes in both groups after 2-year follow-up, apparently the less complex and smaller lesions observed in both the articular cartilage and the labrum of younger patients result in better outcomes compared with older patients.

Imaging of Abductor Tears: Stepwise Technique for Accurate Diagnosis

This article presents the authors' technique for evaluation of possible abductor tears with magnetic resonance imaging (MRI). By using T2 fat-saturated coronal and axial slices of the hip and T1 coronal images of the pelvis, the authors show how to visualize all tears of the abductor tendons and signs of chronic abductor deficiency. After diagnosis has been made, signs that may help the surgeon determine if open or arthroscopic surgery would be best used are reviewed. Finally, the author reviews indications for a gluteus medius repair with concomitant gluteus maximus reconstruction.

Sonoanatomy and Pathology of the Posterior Band of the Gluteus Medius Tendon

Greater trochanteric pain syndrome is a common clinical entity that most often results from disorders of the gluteus medius tendon. There are two distinct bands of the gluteus medius tendon, and abnormalities may affect the anterior or posterior band in isolation or simultaneously. Although abnormalities of the anterior band are more common, awareness and sonographic detection of posterior band abnormalities is essential to guide treatment in the setting of greater trochanteric pain syndrome.

Does menopausal hormone therapy (MHT), exercise or a combination of both, improve pain and function in post-menopausal women with greater trochanteric pain syndrome (GTPS)? A randomised controlled trial

BACKGROUND

Greater trochanteric pain syndrome (GTPS) is pathology in the gluteus medius and minimus tendons and trochanteric bursa that causes debilitating tendon pain and dysfunction, particularly in post-menopausal women. Limited evidence in clinical studies suggests hormone changes after menopause may have a negative effect on tendon. This protocol describes a randomised controlled trial comparing the effectiveness of menopausal hormone therapy (MHT) and exercise therapy in reducing pain and dysfunction associated with GTPS in post-menopausal women.

METHOD

One hundred and sixteen post-menopausal women will be recruited and randomised to receive one of two exercise programs (sham or targeted intervention exercise) and transdermal creams (MHT cream containing oestradiol 50mcg and norethisterone acetate 140mcg or placebo cream). Interventions will be 12-weeks in duration and outcomes will be examined at baseline, 12-weeks and 52-weeks. The primary outcome measure will be the VISA-G questionnaire and secondary outcomes measures will include three hip pain and function questionnaires (Hip dysfunction and Osteoarthritis Outcome Score, Oxford Hip Score, Lateral Hip Pain questionnaire), a global change in symptom questionnaire (using a 15-point Likert scale) and a quality of life measure (AQoL-8D questionnaire). Data will be analysed using the intention to treat principle.

DISCUSSION

This study is the first randomised controlled trial to compare the effectiveness of menopausal hormone therapy therapy alone, and with the combination of exercise therapy, to treat pain and dysfunction associated with GTPS. This study has been pragmatically designed to ensure that the interventions in this study can be integrated into policy and clinical practice if found to be effective in the treatment of GTPS in post-menopausal women. If successful, there is potential for this treatment regimen to be explored in future studies of other persistent tendon conditions in the post-menopausal population.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12614001157662 Registered 31 October 2014.

Ultrasound-Guided Hip Procedures

This article describes the techniques for performing ultrasound-guided procedures in the hip region, including intra-articular hip injection, iliopsoas bursa injection, greater trochanter bursa injection, ischial bursa injection, and piriformis muscle injection. The common indications, pitfalls, accuracy, and efficacy of these procedures are also addressed.

Diagnosis, Evaluation, and Endoscopic Repair of Partial Articular Gluteus Tendon Avulsion

In addition to trochanteric bursitis, gluteus medius and minimus tears (GMMTs) can be a common source of insidious lateral hip pain and dysfunction. Partial-thickness GMMTs are much more common than full-thickness GMMTs but are frequently overlooked by both radiologists and orthopaedic surgeons. GMMTs are commonly identified on magnetic resonance imaging ordered for lateral hip pain unresponsive to conservative management. Imaging can show that high-grade partial articular gluteus tendon avulsion (PAGTA) can occur as either an isolated gluteus medius tear, an isolated gluteus minimus tear, or a combined GMMT. We describe how to identify PAGTA injuries with intraoperative assessment and identification of the interval between the gluteus medius and minimus tendons to allow access to the PAGTA without violating the bursal side of the tendon. PAGTAs can be repaired arthroscopically by single- or double-row suture anchor fixation depending on the size of the tear. The purpose of this article is to guide orthopaedic surgeons in the recognition of PAGTA with magnetic resonance imaging and dynamic examination to allow for accurate repair of GMMTs.