BACKGROUND: Hip replacement surgery is highly effective in relieving pain and improving mobility in patients with various hip conditions. However, some patients develop groin pain after surgery, often due to iliopsoas impingement (IPI), which can be challenging to diagnose. Conservative treatments are initially recommended, but when these are not effective, surgical options may be considered. This study aims to evaluate the clinical outcomes, success and failure rates, revision rates, and complications associated with arthroscopic and endoscopic surgery for IPI, thereby providing a comprehensive understanding of the effectiveness and risks of these surgical interventions.
METHODS: A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including a thorough search of five main databases: PubMed, Scopus, Embase, Medline, and Cochrane. Eligible articles were meticulously evaluated according to predefined criteria for levels of evidence (LoE), with retrospective studies assessed using the Coleman Methodology Score (mCMS). This systematic review was registered in the International Prospective Registry of Systematic Reviews (PROSPERO).
RESULTS: Among the 16 included studies, 431 patients with 434 hips underwent either endoscopic or arthroscopic tenotomy. Both techniques showed favorable outcomes, with arthroscopic tenotomy demonstrating slightly higher success rates than endoscopic tenotomy. Common complications included mild pain and occasional infections, with recurrence observed in some cases. Both techniques offer direct visualization of prosthetic components and potential preservation of psoas function.
CONCLUSIONS: Arthroscopic and endoscopic iliopsoas tenotomy are effective treatments for alleviating symptoms and improving hip function in patients with IPI post-total hip arthroplasty (THA).
METHODS: IV.

OBJECTIVE: This cadaveric study aimed at describing the anatomical variations of the iliopsoas complex.
METHODS: The iliopsoas complex was dissected unilaterally in 28 formalin-embalmed cadavers-13 males and 15 females with a mean age of 85.6 years. The number, courses and widths of the iliacus and psoas major tendons were determined. Patients with previous hip surgery were excluded. The following measurements were taken from the mid-inguinal point: the distance to the point of union of the psoas major and iliacus tendon; and the distance to the most distal insertion of iliopsoas.
RESULTS: The presence of single, double and triple tendon insertions of iliopsoas were found in 12, 12 and 4 of the 28 specimens, respectively. When present, double and triple tendons inserted separately onto the lesser trochanter. The average length of the iliopsoas tendon from the mid-inguinal point to the most distal attachment at the lesser trochanter was 122.3 ± 13.0 mm. The iliacus muscle bulk merged with psoas major at an average distance of 24.9 ± 17.9 mm proximal to the mid-inguinal point. In all cases, the lateral-most fibres of iliacus yielded a non-tendinous, muscular insertion on to the anterior surface of the lesser trochanter and the femoral shaft, rather than joining onto the main iliopsoas tendon(s). The average total width of the psoas major tendon decreased with an increasing number of tendons: 14.6 ± 2.2 mm (single tendon), 8.2 ± 3.0 mm (2 tendons present) and 5.9 ± 1.1 mm (3 tendons present) (P < 0.001).
CONCLUSIONS: The results of this study suggest that multiple tendinous insertions of iliopsoas are present as an anatomical variant in more than 50% of the population. The non-tendinous muscular insertion of the iliopsoas on to the anterior surface of the lesser trochanter and femoral shaft found represents a novel anatomical variant not previously described.
METHODS: Level V.

BACKGROUND: Iliopsoas impingement is a complication of total hip arthroplasty that often manifests as groin pain during initial hip flexion. However, there are no reports of mechanical complications after iliopsoas tenotomy following total hip arthroplasty (THA).
METHODS: We present the case of a 64-year-old woman with degenerative lumbar kyphosis who developed anterior hip dislocations after arthroscopic iliopsoas tenotomy for anterior impingement following THA. She ultimately required revision of the acetabular cup.
CONCLUSIONS: Arthroscopic tenotomy for refractory iliopsoas tendinopathy may be appealing because of its less invasive nature. However, caution should be exercised in the setting of significant cup malpositioning and/or spinopelvic imbalance to avoid iatrogenic anterior instability.

OBJECTIVE: 1 of the causes of groin pain after total hip arthroplasty (THA) is impingement of the iliopsoas tendon. The purpose of this study was to present our results with outside-in arthroscopic tenotomy for iliopsoas impingement after THA.
METHODS: We retrospectively reviewed 12 patients treated between 2009 and 2016 with a minimum follow-up of 2 years. Anterior acetabular component prominence was measured on a true lateral hip radiograph. A transcapsular tenotomy was performed near the edge of the acetabular component through an outside-in arthroscopic approach. The primary clinical outcomes evaluated were groin pain, assessed with a visual analogue scale (VAS), and the Harris Hip Score (HHS). Secondary outcomes included strength of hip flexion, measured with the Medical Research Council (MRC) scale.
RESULTS: All patients had groin pain improvement, though one patient continued to have moderate pain. The mean VAS score was significantly lower postoperatively (1.08) than preoperatively (6.2) (p < 0.001). The mean HHS improved from 58.8 (range, 37-76) to 86.1 (range, 59-98) (p = 0.001). The average postoperative MRC Scale was 4.58. The mean anterior prominence was 7.25 mm (range 3-12 mm). In patients with <10 mm of component prominence, tenotomy provided groin pain resolution in all cases (n = 8). In patients with ⩾10 mm of prominence, symptoms resolved in 3 out of 4 cases.
CONCLUSIONS: Outside-in arthroscopic iliopsoas release provided a high rate of success with no complications in this study, even in patients with moderate acetabular component prominence.

BACKGROUND: Iliopsoas (IP) muscle atrophy is a known consequence of open IP tenotomy, but the severity of IP muscle atrophy that occurs after arthroscopic labral-level IP tenotomies has not been documented.
OBJECTIVE: To document the severity of muscle atrophy that occurs in the iliacus, psoas, and adjacent hip musculature after arthroscopic labral-level IP tenotomy.
METHODS: Case series; Level of evidence, 4.
METHODS: Twenty-eight patients who had magnetic resonance arthrograms (MRAs) obtained prior to and 3 months to 5 years after arthroscopic labral-level IP tenotomies are the basis of this report. The pre- and postoperative MRAs of each patient were examined in consensus by 2 musculoskeletal radiologists who graded the postoperative muscle atrophy from 0 (no fatty infiltration) to 4 (>75% fatty infiltration) and noted any compensatory muscle hypertrophy or abnormal IP tendon morphology. Patients also were assessed with the Byrd 100-point modified Harris Hip Scoring system (MHHS) preoperatively and at the time of their postoperative MRA.
RESULTS: Postoperative MRAs were obtained on average 1.7 years (range, 3 months to 5 years) after hip arthroscopy. None of the patients had muscle atrophy on their preoperative MRAs. In contrast, 89% of patients had iliacus and psoas muscle atrophy on their postoperative MRAs, but only 2 (7%) developed grade 4 atrophy, and the majority (64%) had either grade 1 (n = 15) or no atrophy (n = 3). In addition, there were no significant differences in the MHHS of the patients with mild (grades 0-1), moderate (grades 2-3), or severe (grade 4) postoperative atrophy. Postoperative MRAs also demonstrated low-grade atrophy (grades 1-2) in the quadratus femoris (n = 5) and rectus femoris (n = 1) muscles, and 16 patients (57%) had distortion of the tendon, but none had a gap in their tendon.
CONCLUSIONS: A majority of patients (89%) developed IP muscle atrophy after arthroscopic labral-level IP tenotomies, and although this percentage was similar (89% vs 90%) to that reported with lesser trochanteric IP tenotomies, the patients did not (1) develop atrophy of the gluteus maximus and vastus lateralis muscles, (2) have chronic IP tendon disruption, or (3) develop the severity of IP atrophy (55% grade 4 vs 7% grade 4) that has been reported after arthroscopic lesser trochanteric IP tenotomies.