Anatomical variability of the lumbosacral plexus: A review of clinical implications

Year 2025, Volume: 42 Issue: 4, 473 - 479, 31.12.2025

Mennan Ece Pirzirenli , Büşra Nur Özcan , Sena Kamalı

Abstract

The lumbosacral plexus (LSP) is a complex neural network that provides motor and sensory innervation to the lower limbs, pelvic organs, and perineal region. Although traditionally depicted as a fixed structure in anatomical literature, recent cadaveric dissections, radiological imaging, and surgical observations have revealed significant morphological variations within the LSP. This review synthesizes studies published between 2000 and 2025, classifying and evaluating the prevalence and clinical relevance of anatomical deviations in both lumbar and sacral components of the plexus. Variations in the origin and course of nerves such as the ilioinguinal, genitofemoral, lateral femoral cutaneous, femoral, and obturator nerves pose critical risks during surgical procedures and regional anesthesia. At the sacral level, alterations in the morphology of the piriformis muscle affect the pathway of the sciatic nerve, potentially leading to conditions such as piriformis syndrome, nerve entrapments, and failed nerve blocks. Additionally, anatomical variations of less emphasized nerves like the pudendal and posterior femoral cutaneous nerves carry significant implications for pelvic surgeries. These findings highlight the limitations of relying solely on “average” anatomical models and underscore the necessity of individualized surgical planning. The integration of advanced techniques such as MR neurography and intraoperative neuromonitoring into routine clinical practice can aid in identifying anatomical variations preoperatively, thereby minimizing complication risks and improving patient outcomes.

Keywords

Lumbosacral plexus , anatomical variation , peripheral nerves

Ethical Statement

This article is in the form of review type and the inner content is designed from retrospective archives.

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