Neurologic Complications Following Peripheral Nerve Block in Foot and Ankle Surgery

Abstract

Background: It is often challenging to determine the cause of nerve injury following peripheral nerve block (PNB). The etiology can be multifactorial and may be influenced by patient-specific factors, variation in anesthesia practice, and the location of the nerve block. This study examines the incidence of postoperative neurologic complications following the use of PNB in foot and ankle surgery. The primary goal was to identify PNB characteristics associated with neurologic complications. Methods: A bibliographic search was conducted from 2012 to 2024. Included studies analyzed neurologic complications following the use of PNB in foot and ankle surgery. Studies that included pediatric or pregnant populations were excluded, along with those that involved orthopedic surgeries other than foot and ankle. The primary outcome was complication rate, which included neurologic complications, defined as sensory or motor nerve dysfunction remaining after the period of expected block effect. Analyzed block characteristics included choice of local anesthetic, use of adjuvant, patient position, and level of sedation during block administration. Results: Fifteen studies met criteria for inclusion. Of 6,012 total patients, 794 reported neurologic complications (13.2%). Of these, 2.9% (175 of 6,012) had symptoms that remained unresolved at the last follow-up. Ninety-seven percent of nerve deficits were sensory (770 of 794), 1.8% were motor (14 of 794), and 1.3% were mixed (10 of 794). Popliteal block had a complication rate of 12.2% (400 of 3,273), the highest of any solitary block; of these patients, and 0.3% (11 of 3,273) developed complex regional pain syndrome. Complication rates for bupivacaine and ropivacaine were 8.8% (243 of 2,776) and 24.1% (330 of 1,367), respectively. Comparison of adjuvants yielded complication rates of 24.3% with epinephrine (89 of 367) and 15.5% with corticosteroids (277 of 1,784). Conclusion: While most neurologic complications after PNB involve transient paresthesia followed by spontaneous resolution, some patients develop long-lasting symptoms resulting in chronic pain and motor compromise. Implementation of a screening protocol is needed to identify patients at risk of nerve injury who may be poor candidates for regional anesthesia. Level of Evidence: Level II. See Instructions for Authors for a complete description of levels of evidence.