Vol. 34, N 2

An extensive study and review of literature about multiple variations of the lumbar plexus

Nayak, S. B.; Surendran, S.; Reghunathan, D.; Maloor, P. A.; Shetty, P.

KEYWORDS: lumbosacral trunk, lumbar plexus, femoral nerve, genitofemoral nerve, sacral plexus

ABSTRACT: Introduction: Lumbar plexus involves the L1 L5 spinal segments for the formation of the nerves which supply parts of the abdominal wall, pelvis and the upper part of the thigh (both sensory and motor). Our aim in this study was to compile all the rare variations found in a single cadaver, which is of the rarest possible kind. Methods: During the dissection of the abdomen and pelvis in approximately 70 year old cadaver, there were multiple variations observed in the anatomy of the lumbar plexus. The entire region was cleaned for visibility of the variations and all those were clearly documented for compiling purpose. Results: The following variations in the formation of the lumbar and sacral nerves were observed. 1. The genitofemoral nerve bifurcated at a higher level; genital branch of genitofemoral nerve gave branches to the anterior abdominal wall muscles, 2. A communicating branch was given from the lateral cutaneous nerve of thigh to the medial cutaneous nerve of thigh, 3. A muscular branch was given from femoral nerve to psoas major, 4. There was absence of contribution of L4 spinal nerve in the formation of the lumbosacral trunk, and 5. Lumbosacral trunk gave communicating branches to the femoral and obturator nerves. Most of the variations found were rare and finding all the above said variations in a single cadaver is even rare. Conclusion: Knowledge of the normal anatomy and any possible variations would help the clinicians and surgeons dealing with this region and avoid possible complications beforehand.