Anatomy of the sural nerve in a sample of South African human adult cadavers.

The sural nerve (SN) is a sensory nerve in the lower limb with notable variability in its origin, course, and branching patterns. This variability has important implications for diagnostic procedures, nerve grafting, and surgical planning, yet it remains underexplored in Southern African populations. This cadaveric study examined 90 lower limbs from 45 embalmed adult human cadavers (24 males, 21 females) at the University of Pretoria in South Africa. Each specimen was assessed for SN formation type, anatomical location, and morphometric data, including its contributing branches (medial sural cutaneous nerve [MSCN] and lateral sural cutaneous nerve [LSCN]). Measurements were recorded, and bilateral symmetry and sex-based differences were analyzed. Four SN formation types were identified, with Type 1 (union of MSCN and LSCN) being most common (62.2%). Formation most frequently occurred in the middle third of the leg (38.9%), although distribution across the middle, lower, and ankle levels was more evenly spread than in other populations. Bilateral symmetry in SN formation was seen in only 40% of cadavers. The average SN length was 100.1 mm and the mean distance from the lateral malleolus was 27.2 mm. This study confirms high anatomical variability of the SN among South African cadavers, and understanding such variation is crucial for clinicians performing nerve grafting or procedures in the distal leg. These findings may enhance surgical planning and education by emphasizing region-specific anatomical variation.