Amos Armony, BA
Medical Student
University of Massachusetts Medical School
Springfield, Massachusetts, United States
Andrew J. Duarte, MD
Assistant Professor of Orthopedics and Physical Rehabilitation
University of Massachusetts Medical School
Worcester, Massachusetts, United States
Using a high frequency linear probe, two branches of the AFCN above the sartorius and quadriceps muscles were identified. Following sterilization and local anesthetic administration, a handheld cryoneurolysis device (Iovera, Pacira Biosciences) was used, causing axonal degeneration at both branches of the AFCN. Following the procedure, MS reported pain reduction from 6/10 to 2/10 and decreased dysesthesia. She can walk at home without assistance but uses a cane for community mobility.
Discussions: The AFCN, a sensory branch of the femoral nerve, has two main branches that innervate the medial and anterior thigh. Following cardiac catheterization procedure, injury to the femoral artery led to pseudoaneurysm which compressed the AFCN and caused neurapraxia. The technique of cryoneurolysis applies extreme cold to nerve tissues, inducing localized axonal degeneration while preserving the myelin sheath, allowing for eventual nerve regeneration. Although radiofrequency nerve ablation (RFNA) with fluoroscopic guidance was considered, it was deemed difficult due to the lack of bony landmarks and the risk of burns from the superficial AFCN. Cryoneurolysis with ultrasound guidance proved to be a better alternative.
Conclusions: This case highlights cryoneurolysis with ultrasound guidance as a viable option when RFNA is impractical or risky. It suggests an increasing role for cryoneurolysis in treating superficial neuropathic pain.
