Proximal endoscopic repair of the hamstring tendons: a cadaveric anatomical study of posterior hip portals.

Arthroscopy and endoscopic hip surgery have attracted increasing attention in the orthopedic field. In the case of arthroscopy, portals and their relationships with neurovascular bundle structures at risk are well established. However, studies on endoscopic portals used for the repair of hamstring tendon injuries are insufficient. Hamstring injuries are the most common muscle injury in sports medicine, and up to 12% can present as a tendon rupture. Endoscopic surgery is advantageous because it has a lower rate of bleeding and avoids excessive handling of the gluteal muscles. The objective of this study is to perform an anatomical evaluation of endoscopic portals for hamstring repair and measure their distance to neurovascular structures-mainly sciatic nerve and posterior femoral cutaneous nerve (PFCN). Fifteen hips from frozen and formalized cadavers were evaluated. Specimens that showed any modification in their anatomy were excluded. Portals were simulated using Steinmann pins, and anatomical dissection was performed. Distances from neurovascular structures were measured using a digital caliper. Four male cadaver hips (26%) and eleven female cadaver hips (74%) were included. Two dissected hips presented PFCN injury through the posterolateral portal- mean 20.28 mm (±8.14), and one through the distal accessory portal- 21.87 mm (±12.03). The injury rate for PFCN was 3/15 or 20%. None of the portals presented sciatic nerve injury. Conclusion: There is an imminent risk of nerve injury to the PFCN by performing the lateral portals for hamstring repair. To avoid this, we recommend starting the procedure through the most medial (posteromedial) portal, and the other portals must be performed under direct visualization.