Morphologic and morphometric bilateral analysis and sexual dimorphism in sciatic nerves of adult cadaveric specimens in Uganda

Abstract

BACKGROUND: The Sciatic nerve (SN) exhibits distinct sex and side-related differences, which have significant implications for clinical practice. The study investigated the sex and side-related morphologic and morphometric variations of the nerve using cadavers. METHODS: This is a cross-sectional cadaveric study involving 62 Ugandan cadavers. Continuous variables were reported using descriptive statistics and discrete variables were reported as percentages. Ordinary two-way ANOVA was used to compare the dimensions and proportion of the patterns of the SN. RESULTS: The study identified six categories of exit patterns of the SN, type A ("Below and undivided") occurred in a majority of cases (62.9%). A penta-furcate branching pattern dominated the whole population. Bifurcate termination pattern was found in most SNs (90.3% and 87.1% for right and left limbs respectively) while the rest have the trifurcate termination pattern, with no side or sex-related variations. The average dimensions of SN were within normal ranges, and showed no side-related differences but with a sex difference (significantly higher in males than females), mean length of the SN in centimetres (length A: Males, right limbs = 30.58 ± 9.00; left limbs = 31.30 ± 6.20; Females, right = 26.07 ± 6.58; left = 26.30 ± 5.56). The difference in the length "A" for the males left limb and females right limb was statistically significant with a p-value of 0.0195. CONCLUSIONS: Most of the examined SNs showed normal anatomical characteristics with rare cases of sex-related dimorphism in the termination level and morphometry (length and diameter) of the nerve. The observed sexual dimorphisms in sciatic nerves are of clinical and surgical interest; hence, suggesting the need for further investigations in different populations, especially using advanced techniques such as ultrasonography anatomic techniques.