Anatomical Variations in Formation and Branching Pattern of the Border Nerves of Lumbar Region

Abstract

Abstract Background Ilioinguinal, iliohypogastric, and genitofemoral nerves are together known as “border nerves” of the lumbar plexus. Aim of this study was to find out the variations in formation and branching pattern of these nerves and correlate with their clinical relevance. Materials and Methods For this study 30 formaldehyde preserved cadavers were used, and the nerves were studied on both the sides, thus making the sample size of 60. Results Iliohypogastric nerve was absent in 6.6% and double in 1.6%. It was prefixed with a twig from T12 in 6.6% and had origin from both L1 and L2 in 1.6%. The ilioinguinal nerve was absent in 3.3% and double in 3.3%. The genitofemoral nerve exhibited a large number of variations. It was absent in 1.6%. Early division of the nerve prior to emergence from the psoas major muscle was noticed in 13.3%, and early division soon after emergence from the muscle was noted in 3.3%. In one cadaver, on one side, genital branch was absent, and it continued as femoral branch only. In another cadaver, the nerve continued as genital branch only. In two other cases, genital and femoral branches were seen to arise separately from the lumbar plexus. The nerve had its origin from L1 and L2 in 25%, L2 and L3 in 25%, L1 in 3.3%, L2 in 46.66%, and L3 in 1.6% of the cases. Conclusion Knowledge of these variations would be of immense help during surgical approach and giving nerve block for anesthesia and postoperative analgesia in this region.