Endoscopic gluteus maximus tendon release for external snapping hip syndrome: a functional assessment

Purpose The aim of this retrospective study was to investigate the clinical follow-up of patients with external snapping hip syndrome (ESHS) treated with endoscopic gluteus maximus tendon release and to compare the residual muscular strength and thigh circumference as an indirect outcome measure. Methods Patients of all ages with external snapping hip syndrome were treated with endoscopic gluteus maximus tendon release. Outcome measures evaluated included: visual analog scale (VAS), modified Harris Hip Score (mHHS), and Non-Arthritic Hip Score (NAHS). The gluteus maximus strength and the circumference of the thigh were also evaluated. Results Among 25 patients, 23 fulfilled the inclusion criteria and one patient was lost to follow-up. The series included 22 patients, 6 males and 16 females with a mean age of 27.9 ± 13.4 years (range 16–76 years). All patients had resolution of the snapping symptoms after the procedure. The mean follow-up was 18 ± 9.3 months. All outcomes improved in a statistically significant manner: VAS value decreased from 6.8 (range 6–8) to 0.6 (range 0–4) (p < 0.001), mHHS increased from 48.6 (range 17.6–67) to 88.2 (range 67–94.6) (p < 0.001), NAHS increased from 49.0 (range 21.5–66) to 90.8 (range 66–98.75) (p < 0.001). A statistically significant reduction of operated limb thigh circumference compared to the contralateral side (3.7%) was also found, while there were no statistical differences regarding the strength of gluteus maximus muscles. Conclusions Endoscopic gluteus maximus tendon release is an excellent surgical option to treat snapping hip syndrome. The evaluated muscle strength revealed no functional impairment. The significance of the limb circumference reduction has yet to be determined. Level of evidence IV: retrospective comparative trial.

External snapping hip syndrome is associated with an increased femoral offset

Background External snapping hip syndrome (ESH) is postulated to be one of the causes of greater trochanteric pain syndrome, which also includes greater trochanteric bursitis and tendinopathy or tears of the hip abductor mechanism. However, it was not yet described what kind of bony morphology can cause the snapping and whether symptomatic and asymptomatic individuals have different imaging features. Purpose It was the purpose of this study to look for predisposing morphological factors for ESH and to differentiate between painful and asymptomatic snapping. Methods A consecutive cohort with ESH and available magnetic resonance imaging (MRI) between 2014 and 2019 was identified. The control group consisted of patients that underwent corrective osteotomies around the knee for mechanical axis correction and never complained of hip symptoms nor had undergone previous hip procedures. The following parameters were blindly assessed for determination of risk factors for ESH: CCD (corpus collum diaphysis) angle; femoral and global offset; femoral antetorsion; functional femoral antetorsion; translation of the greater trochanter (GT); posterior tilt of the GT; pelvic width/anterior pelvic length; intertrochanteric width. Hip and pelvic offset indexes were calculated as ratios of femoral/global offset and intertrochanteric/pelvic width, respectively. For the comparison of symptomatic and asymptomatic snapping, the following soft-tissue signs were investigated: presence of trochanteric bursitis or gluteal tendinopathy; presence of surface bony irregularities on trochanter major and ITB (Iliotibial band) thickness. Results A total of 31 hips with ESH were identified. The control group (n = 29) consisted of patients matched on both age (± 1) and gender. Multiple regression analysis determined an increased hip offset index to be independent predictor of ESH (r = + 0.283, p = 0.025), most likely due to the higher femoral offset in the ESH group (p = 0.031). Pearson correlation analysis could not identify any significant secondary factors. No differences were found between painful and asymptomatic snapping on MRI. Conclusions A high hip offset index was found as an independent predictor for external snapping hip in our cohort, mainly due to increased femoral offset. No imaging soft-tissue related differences could be outlined between symptomatic and asymptomatic external snapping. Level of evidence III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00590.

Mid- to long-term clinical outcomes of arthroscopic surgery for external snapping hip syndrome

ABSTRACT This study evaluated the outcomes of arthroscopic surgery for the treatment of external snapping hip at 2- to 10-year follow-ups. Eighteen patients with refractory external snapping hip treated by arthroscopic surgery were enrolled in this prospective study. All patients underwent unsuccessful conservative treatment for more than 3 months before surgery. We made diamond-shaped defects on the iliotibial band and resected peripheral fibrosis tissues for iliotibial band release with an arthroscopic approach. The visual analog scale (VAS), modified Harris hip score and return to previous level of activity were evaluated as functional outcomes. In addition, residual discomfort or the presentation of complications was also investigated. The average follow up period was 7 years. The modified Harris hip score increased from 70.08 preoperatively to 93.14 postoperatively, and the VAS score decreased from 3.67 preoperatively to 1.17 2 weeks after the operation and declined to 0.33 at the last follow-up. Neither recurrence of snaps nor complications were recorded. Two patients complained of a tight sensation with tenderness after exertion. Our clinical outcomes were compatible with those of previous studies, and no long-term complications were noted, even with a relatively longer follow-up period than what was reported in previous studies. Arthroscopic surgery is a safe and effective treatment that can provide promising long-term clinical outcomes for patients with refractory external snapping hip.