Anatomical variation of the sciatic nerve division in the cadaver studies: a systematic review and meta-analysis

The extent and patterns of variability in the sciatic nerve (SN) division are not well documented in cadaver studies. This review aimed to determine the pooled prevalence and distribution patterns of anatomical variations in the SN division, from existing cadaveric studies, and to explore their potential clinical implications. Articles were searched in PubMed, Google Scholar, ScienceDirect, African Journals Online, and other relevant sources. Stata 14 software was used for data analysis. The prevalence was calculated using a random-effects model. Heterogeneity was assessed using the Cochran Q test and the I² values of a forest plot. Publication bias was checked using funnel plots and Egger's test. Twenty cadaver studies were used for this systematic review and meta-analysis. In this study, the pooled prevalence of the anatomical variation of the SN division was approximately 31.01% (95% CI: 16.24-45.78). The subgroup analysis demonstrated the highest variability within the popliteal fossa (21.17%; 95% CI: -2.01-44.34), followed by the pelvic region (11.13%; 95% CI: 5.85-16.40), the middle third of the thigh (7.11%; 95% CI: 3.67-10.55), the gluteal region (4.86%; 95% CI: 2.03-7.69), and the upper third of the thigh (4.74%; 95% CI: 1.71-7.76). In this study, the anatomical variation of the SN division was high, and one in three divisions was outside the typical pattern. The variation of SN division may affect intramuscular injections and surgical procedures.