Thomas D. Beck Jr., D.O.,
Richard Kruse, D.O.
Alfred I. duPont Institute
1600 Rockland Road
Wilmington, Delaware 19803
INTRODUCTION: Multiple reports of ganglion cysts involving peripheral nerves have appeared in the literature. The nerve most frequently involved is the common peroneal. Most reports are either individual cases or small series. Compression of the common peroneal nerve by intra- or extraneural ganglion cysts in children is rare. A review of the literature reveals only five cases in patients less than eighteen years of age, the youngest being nine. The most common presenting symptoms are pain, swelling, sensory dysfunction, and motor dysfunction.
MATERIALS AND METHODS: A case is presented of a three year old male with initial complaint of pain and intoeing. Patients symptoms progressed with increasing pain, sensory changes, and eventually a foot drop. Pre-operative evaluation including physical exam, laboratory studies, imaging studies, and electromyelography will be presented. Intra-operative findings, pathology, and post-operative course will be discussed.
RESULTS: Patient was found to have cystic mass causing compression of the common peroneal nerve. Intra-operatively an extraneural ganglion cyst was identified arising from the tibio-fibular joint. Microscopic analysis showed a ganglion cyst with adjacent and partially incorporated peripheral nerve. Patients symptoms eventually resolved following cyst excision with complete return of sensory and motor function. There was no evidence of recurrence of the cyst at one year follow-up.
DISCUSSION: The origin of ganglion cysts found in the peroneal nerve is controversial. One theory proposes that ganglion arises from the superior tibiofibular joint and tracks along the sheath of the small recurrent articular nerve. A second theory states that ganglion arises within the nerve itself from cystic degeneration of perineural tissue. A third theory is that these intraneural cystic structures are formed from myofibroblasts outside of the nerve and subsequently invade the nerve sheath. In our case the cyst appeared to be extraneural intra- operatively, however microscopic analysis of the specimen showed peripheral nerve incorporated in the ganglion cyst. This seems to suggest invasion of the nerve by the ganglion as the origin in this case.
[Return to Table of Contents, Back to Research Symposium Home Page, Orthopaedic Department Home Page,]