Intrasheath Peroneal Tendon Subluxation: A Report of Three Cases with Technical Note.

Peroneal intrasheath instability is a painful popping sensation and audible clicking of the lateral ankle. This condition is not commonly reported, and its exact incidence remains unknown. It consists of a transient retromalleolar subluxation of the peroneal tendons, with an abnormal motion of the peroneal tendons relative to each other, with the superior peroneal retinaculum intact. Diagnosis requires high clinical suspicion and dynamic ultrasound is the best imaging study to evaluate peroneal instability when the superior peroneal retinaculum is intact, for diagnosing peroneal intrasheath instability. The goal of the present study is to describe how to reach the diagnosis and to describe and evaluate the surgical technique for the treatment of this pathology. In the present report, we describe three cases of this pathology that received successful surgical treatment with peroneal groove-deepening procedure and retinaculoplasty of the superior retinaculum. This surgical technique provides good outcomes when conservative treatment fails.