Orthopaedic MD

Poster presented to 8th EFORT Congress 2007

C. Jackman, D. Sokol, K. Applegate, K. Kayes, W. Mahmud: Foot Drop Due To Peroneal Ganglion Cyst In An Adolescent. The Internet Journal of Neurology. 2005. Volume 3 Number 2.
A 14 year-old male tennis player presented with a gradually progressive left foot drop. Three weeks prior, he found a knot behind his left knee that resolved. Sagital MRI T2-weighted images of the left knee demonstrated a lobulated, cystic mass, antero-lateral to the fibular head. Upon excision, a ganglion cyst was found to be compressing the common peroneal nerve. The child recovered at three months.
Keywords: Foot drop, nerve compression, ganglionic cyst

A ganglion is described as "...a tumour-like collection of viscous fluid encapsulated by a fibrous sheath." (Jaffe and Jones, 1994, p.248). About 4% of ganglia occur in the feet (Potter, 1992), and perhaps this explains why there is relatively limited literature written on the subject of foot ganglia. Most commonly identified on the dorsum of the wrist, ganglia are the most frequently encountered tumour-like lesion found on the dorsum of the ankle or foot, often associated with tendon sheaths and possibly communicating with the nearest joint capsule. This project is divided into sections as follows:
* Etiology
* Incidence
* Clinical presentation
* Diagnosis
* Treatment
* References

Ganglia are the commonest lumps referred to the Foot and Ankle Service. The commonest sites are the dorsolateral aspect of the foot; a few are related to the great toe or the ankle. They are commoner in women, with 55-83% reported in different series. They may occur at any age; the average age is about 40 years, slightly older than in the wrist.
The aetiology and pathogenesis of ganglia remains a controversy unencumbered by evidence.

Sudden onset loss of ankle dorsiflexion is rarely caused by compression of the common peroneal nerve by ganglion cysts. Peroneal nerve ganglion cysts typically present with a palpable mass or features of entrapment neuropathy, including pain, gradual onset motor and sensory weakness. Ganglion cysts are common in upper extremity, most often occurring in the wrist.1 They are relatively uncommon in the lower extremity, most commonly involving the peroneal nerve.
Rajinder Singh Gaheer, Jamie Mckenzie, Maurice Paterson J.Orthopaedics 2006;3(4)e20