The sinus tarsi represents a collection of ligaments on the dorsolateral aspect of the ankle that can be torn during ankle inversion sprains or fractures. The innervation of the sinus tarsi has been demonstrated by Rab, Ebmer, and Dellon (2001) to be from terminal branches of the deep peroneal nerve. Just as injury to the wrist joint can damage the terminal branch of the posterior interosseous nerve, it was hypothesized that dorsolateral ankle pain after ankle injury, the sinus tarsi syndrome, might be due to traumatic neuromata of these terminal nerve branches. Our first clinical experience with the results of denervation of the sinus tarsi are presented.

In ten patients, the etiology of the pain was inversion sprain in 8, ankle fracture in 1 and MBA-flatfoot implant in 1 patient. The mean post-injury time was 13.5 months. Each patient had failed conservative treatment, including NSAIDs, orthotics, steroid injections, and each had no residual bone deformity requiring treatment. Each patient had relief of pain with a block of the deep peroneal nerve proximal to the ankle joint.

Denervation was done 4 cm proximal to the ankle joint, preserving the sensory component to the first dorsal webspace and a portion of the innervation of the extensor brevis muscle. The technique will be illustrated.

At a minimum of 6 months of post-operative follow-up, 7 of the patients (70%) were completely free of pain, able to wear normal shoes, and had returned to work. In two of the patients, there was a small degree of residual pain, but they were able to resume normal activities and wear normal footwear (20%), and in one patient there was some pain relief, but the patient was not able to resume normal activities.