Objectives: To document the anatomical variation of the lateral femoral cutaneous nerve (LFCN) at the proximal aspect of the thigh and to determine its susceptibility to injury during total hip arthroplasty via a direct anterior approach (DAA).Methods: We obtained 64 thighs from formalin-preserved cadavers of 45 Japanese individuals. LFCN was identified at the level of the inguinal ligament. All nerve branches of the LFCN were carefully traced distally in the subcutaneous tissue. The branching pattern and distribution at the proximal aspect of the thigh were described. A safe zone to avoid LFCN injury in DAA was estimated for the skin incision.Results: The branching pattern of LFCN was highly varied. There were 37% of the anterior type, characterized by a thicker anterior branch, which coursed along the medial border of the tensor fascia lata (TFL) muscle with thinner branches. There were 63% of the posterior type, characterized by posterior branches thicker than or equal to the anterior branch. In 27 of 64 thighs (42%), the LFCN crossed the skin incision along the midline of the TFL muscle.Conclusion: LFCN showed anatomical variation of anterior and posterior branches and 42% were in danger of injury during DAA.
Keywords: Cadaveric study; direct anterior approach; lateral femoral cutaneous nerve; total hip arthroplasty.