Comparable Injury to the Indirect Head of the Rectus Femoris During Interportal and Periportal Capsulotomy: A Cadaveric Study

BACKGROUND: There is concern for maintaining the integrity of the reflected head of the rectus femoris during arthroscopic hip joint access. Because of the proximity to the indirect head of the rectus femoris (IHRF), capsulotomy technique and capsular closure during routine hip arthroscopy may play a role in postoperative tendinitis. PURPOSE: To quantify the extent of injury sustained to the IHRF during interportal versus periportal capsulotomy for routine arthroscopic hip joint access. STUDY DESIGN: Controlled laboratory study. METHODS: A cadaveric study was conducted using 20 fresh-frozen cadaveric hips, in which hip joint access through a periportal capsulotomy (n = 10) or interportal capsulotomy (n = 10) was performed. Capsular closure followed by a layered dissection to the capsuloligamentous complex of the hip joint was then performed to localize the IHRF. Suture proximity to the tendon, tendon disruption, and the IHRF footprint was documented to the nearest 0.01 mm using digital calipers. Statistical analysis was performed using unpaired Student t tests. RESULTS: The mean capsulotomy length for the interportal specimens was 19.27 ± 3.25 mm, and the mean medial and lateral capsulotomy length for the periportal specimens was 4.47 ± 1.60 and 4.26 ± 0.89 mm, respectively. There was violation of the tendon in 3 of 10 interportal specimens and 4 of 10 periportal specimens. There was no significant difference in the closest suture measured to the IHRF for specimens with versus without tendon violation, for either interportal or periportal capsulotomy. CONCLUSION: We found comparable outcomes with regard to violation of the IHRF between interportal and periportal capsulotomy, with no significant difference in suture proximity to the IHRF in specimens with or without tendon violation. There remains no consensus on the ideal method by which to avoid iatrogenic damage to the IHRF. CLINICAL RELEVANCE: Our findings provide insight that may lead to future advances in surgical care, such that protection of the tendon during routine hip arthroscopy may allow for improved postoperative rehabilitation and strength.