SAFETY OF INFRAPATELLAR BRANCH OF THE SAPHENOUS NERVE DURING ACL RECONSTRUCTION: ANATOMICAL AND CLINICAL STUDY Ayman Ahmed Khanfour, El Sayed Aly Mohamed Metwally, and Bahaa Ahmed Motawea* Departments Anatomy and Orthopaedic Surgery*, Faculty of Medicine, Alexandria University.
Introduction: Damage to the infrapatellar branch of the saphenous nerve (IPBSN) has been described during knee arthrotomy and arthroscopy. The true incidence of damage to this nerve during anterior cruciate ligament (ACL) reconstruction has been reported as a complication of arthroscopic examination and surgery of the knee. Aim of the work: To define the anatomy of IPBSN at the level of the joint line to be avoided during surgical procedures at the posteromedial corner of the knee. Also, to assess safety of a new incision for graft harvesting in arthroscopic ACL reconstruction using hamstring tendons autograft. Material & Methods: 76 patients using hamstring tendons autograft. A comparison between horizontal posteromedial and standard vertical anteromedial incisions were done as regard morbidity. The anatomical part of the study included cadaveric dissection of the medial aspect of 30 male knees preserved in formalin from the dissecting rooms of the Faculty of Medicine, Alexandria University. The detailed anatomy of IPBSN was done. Results: There is less morbidity and better cosmoses with horizontal posteromedial incision. There is a safe trapezoid area for entry of knee arthroscopy. This area is determined by middle of the medial border of the patella and a second point 30 mm on the vertical line below it, the third point at the apex of the patella and the fourth point is 15 mm in a vertical line descending from it. Conclusion: Horizontal posteromedial incision for harvest of semitendinosus and gracilis tendons for ACL reconstruction has lower morbidity incidence.