Objectives The objective of this case report is to describe a femoral nerve injury after a psoas compartment block (PCB) and to discuss the probable mechanisms of injury and neuron regeneration. To date, this is the first report of severe femoral nerve injury after PCB.

Case Report A 60-year-old, American Society of Anesthesiologists II woman underwent right total knee replacement under general anesthesia and continuous PCB for postoperative analgesia. Postoperatively, she showed signs of severe femoral nerve injury. A physical therapy program and muscle electrical stimulation were instituted and continued for 6 months. The patient recovered completely with no residual motor or sensory deficit and had no other complication.

Conclusions Severe nerve injuries after regional anesthesia techniques remain infrequent and probably unreported. Our case report suggests that severe femoral nerve injury should be added to the list of reported complications during PCB. This case report is also encouraging because it shows the possibility of a good recovery after such injury.