Medial Thigh Anatomy in Female Cadavers: Clinical Applications to the Transobturator Midurethral Sling

Abstract

Mesh resection for refractory pain after transobturator midurethral sling may require exploration of structures different than those involved in insertion. Our objective was to describe the muscular and neurovascular anatomy of the medial thigh compartment. Dissections were performed in unembalmed female cadavers. Relationships of medial thigh structures were evaluated relative to the midpubic arch and obturator nerve. An out-to-in transobturator tape was passed in a subset of cadavers, and its relationships to the obturator nerve and adductor muscles were examined. Descriptive statistics were used for analyses. Sixteen cadavers were examined. The adductor longus muscle was a median of 37 mm (26-50) from the midpubic arch with tendon length of 26 mm (12-53) and width of 16 mm (14-29). The gracilis was 21 mm (17-26) from the midpubic arch with tendon length of 28 mm (15-56) and width of 45 mm (31-68). The obturator nerve was 58 mm (51-63) from the midpubic arch with width of 5 mm (4-7). No differences between measurements in the supine and lithotomy positions were noted. The transobturator tape was 42 mm (30-47) from the midpubic arch, 36 mm (30-44) from the obturator nerve, and 20 mm (5-31) from the closest obturator nerve branch. The transobturator sling passed through the gracilis muscle in all specimens with variable passage through the adductors longus (75%) and brevis (25%). Familiarity with the medial thigh is essential for surgeons utilizing transobturator midurethral slings. Risks of mesh excision should be weighed against benefits before extensive thigh dissection for pain-related indications.