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Updated: Oct 15, 2025

Posterior Approach for Debridement of the Psoas Abscess
Published on: March 2, 2020
Iliacus minor and psoas quartus muscles traversing the femoral nerve
Abstract:
Anatomical variations of the nerves of the body can be relevant to surgical approaches anesthetic blockade, and other region procedures. Herein, we report a case of three muscle fascicles of the variant psoas quartus and iliacus minor muscles traversing the femoral nerve. Salient literature is reviewed regarding this phenomenon. Variations in the femoral nerve, such as illustrated in the current case, could also help explain hip and thigh pain, and failure of traditional anesthetic placement to block sensation from the femoral nerve completely. Given the procedural relevance of variations in the femoral nerve, further characterizations of nontraditional courses could help to avoid nerve injury during interventions.
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