Anatomical Variations of Origin of Femoral Nerve- A Cross-sectional Observational Study

Abstract

Introduction: Femoral nerve is an important nerve supplying the lower limb. Variations in the origin and course of femoral nerve are frequently encountered. The knowledge of these is of vital importance for orthopaedic surgeons and anaesthetists to prevent iatrogenic injury and debilitating postoperative complications. Aim: To document the variations in origin and course of femoral nerve and its clinical significance. Materials and Methods: A cross-sectional study was conducted on 50 specimens by dissecting 25 embalmed adult human cadavers of South Indian population out of which 20 were male and five were female cadavers. The study was conducted by dissection method done in the Department of Anatomy in Sri Siddhartha Medical College, Tumkur and Sri Siddhartha Institute of Medical Sciences and Research Centre, T Begur, Bangalore Rural, Karnataka, India. Results were expressed in terms of frequency and percentages. Results: Out of the 50 specimens, in 47 specimens femoral nerve was found to be originating normally from dorsal divisions of L2, L3, L4 spinal nerves, whereas in three specimens it was found to be originating from dorsal divisions of L1, L2, L3. In two specimens femoral nerve was seen emerging from behind the psoas major muscle. Conclusion: A good knowledge about the embryological basis and variations in the branching pattern of femoral nerve is essential because of its numerous clinical implications, especially in localising neurological lesions of nerves, for their early and accurate diagnosis and thus preventing iatrogenic anaesthetic complications.

Keywords

• entrapment neuropathy
• nerve block
• prefixed lumbar plexus
• psoas abscess
• psoas block
• spinal anaesthesia