Abstract
Background The lateral femoral cutaneous nerve (LFCN) plays a vital sensory role, innervating the skin of the anterior and lateral thigh. It originates from the lumbar plexus, primarily from the L2 and L3 spinal nerves, and typically exits the pelvis beneath the inguinal ligament to reach the femoral area. However, the LFCN shows significant anatomical variability, both in its course and branching patterns. These variations can be influenced by individual factors such as body size and structural differences. The relationship between the LFCN and key landmarks, such as the anterior superior iliac spine (ASIS), the inguinal ligament, and the sartorius muscle, is crucial for accurately locating the nerve during surgical procedures. Variations in the anatomy of the LFCN are clinically significant, particularly in surgeries involving the inguinal and hip regions. Surgeons performing procedures like inguinal hernia repairs, hip arthroplasty, iliac bone grafting, and abdominal surgeries need to be aware of these variations to minimize the risk of nerve injury. Failure to properly identify or inadvertently injure the LFCN during surgery can lead to conditions such as meralgia paresthetica, which causes numbness and tingling along the lateral thigh. A thorough understanding of the LFCN's anatomical diversity is essential to prevent such injuries and improve surgical outcomes.
Aim The purpose of this study was to explore the anatomical variability of the lateral femoral cutaneous nerve (LFCN) relative to critical landmarks, including the anterior superior iliac spine (ASIS), the inguinal ligament, and the sartorius muscle. This research aimed to document variations in the nerve's path, branching patterns, and its interactions with surrounding structures, with a specific focus on the nerve's origin and trajectory within the pelvis and abdominal regions. By examining these variations, the study sought to offer practical insights for surgical planning in the inguinal and femoral areas, aiming to reduce the risk of nerve damage during common surgical interventions. The study's goal was to improve the safety of surgeries like inguinal hernia repairs, hip replacements, and other abdominal surgeries by providing detailed anatomical data on the LFCN's
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variability. Ultimately, the research aims to contribute to better surgical outcomes and patient care by offering evidence that helps tailor surgical approaches to individual anatomical differences.
Method This study used a qualitative approach involving cadaveric dissection of 30 human specimens. The specimens were sourced from a formalin-preserved collection and were dissected to trace the course of the LFCN from its origin in the lumbar spine (typically at the L2 and L3 levels) to its exit beneath the inguinal ligament and its branching patterns in the femoral region. Anatomical landmarks such as the ASIS, the inguinal ligament, and the sartorius muscle were identified and used as reference points. Special attention was given to variations in the LFCN’s course, including its relationship with the ASIS, the inguinal ligament, and surrounding musculature. The nerve's branching patterns were recorded, noting deviations from standard anatomical descriptions. Measurements were taken to quantify the distances between the LFCN and these key landmarks, allowing for a better understanding of the variability in the nerve’s position across different specimens.
Procedure The dissection procedure began by locating the origin of the LFCN within the lumbar plexus, typically at the L2 and L3 levels. The nerve's path through the pelvic cavity was traced, focusing on its trajectory relative to the inguinal ligament, ASIS, and sartorius muscle. The inguinal ligament served as a key reference point for tracking the nerve’s course as it exited the pelvis toward the femoral region. Special attention was given to variations in the nerve’s location, including whether it passed beneath, above, or through the inguinal ligament. The nerve’s branching patterns were thoroughly examined, and measurements were taken at several points to document deviations from the typical anatomical course. A detailed analysis of the nerve’s position in relation to bony landmarks and surrounding muscles was performed. The dissection also included observations of the relationship between the LFCN and the sartorius muscle, as the nerve often runs close to this muscle. After completing the dissections, the data were analyzed to assess the variability in the nerve’s anatomy, providing insight into its clinical significance.
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Results The study found considerable variability in the anatomical course of the lateral femoral cutaneous nerve (LFCN). While most specimens followed the typical path beneath the lateral portion of the inguinal ligament, significant variations were observed in its exact trajectory and branching patterns. In some specimens, the nerve passed through or above the inguinal ligament rather than beneath it. The origin of the LFCN also varied, with the nerve arising from different levels of the lumbar spine, including as low as the L4 level. The branching patterns of the LFCN showed substantial variability, with some specimens exhibiting additional branches or more distal bifurcations. The position of the nerve relative to the ASIS and inguinal ligament varied as well, with some nerves located more medially or laterally. These findings highlight the importance of recognizing the full spectrum of anatomical variations of the LFCN, as they can affect surgical planning and reduce the risk of inadvertent nerve damage.
Conclusion This study underscores the significant anatomical variability of the lateral femoral cutaneous nerve (LFCN) and the importance of considering these variations in surgeries involving the inguinal and hip regions. The findings indicate that the traditional anatomical descriptions of the LFCN do not universally apply, and variations in its position relative to landmarks such as the ASIS, inguinal ligament, and sartorius muscle must be factored into preoperative planning. Procedures like inguinal hernia repairs, hip arthroplasty, iliac bone grafting, and abdominoplasty can benefit from a deeper understanding of the LFCN's anatomical variability. By tailoring surgical techniques to the individual anatomy of the LFCN, the risk of iatrogenic injury and conditions like meralgia paresthetica can be minimized, leading to better patient outcomes. The study also suggests considering a "safe zone" of approximately three centimeters from the ASIS during surgical interventions in the inguinal region to avoid inadvertent nerve damage. Overall, the insights gained from this study enhance our understanding of the LFCN's role in clinical practice and contribute to safer, more effective surgical procedures.