Prevalence of ganglion cysts originating from the proximal tibiofibular joint: A magnetic resonance imaging study.

Purpose: To determine the prevalence of proximal tibiofibular ganglion cysts in patients undergoing outpatient magnetic resonance imaging (MRI) of the knee.

Type Of Study: Observational cross-sectional study.

Methods: From November 2000 to June 2001, every MRI of the knee performed at an outpatient imaging center was reviewed by a single examiner for the presence of a proximal tibiofibular ganglion cyst. In addition to the reason for ordering the MRI, demographic information on all patients was gathered.

Results: A total of 654 knee MRI scans were performed at the outpatient imaging center during the study period. This study population consisted of 310 men and 344 women, with an average age of 43.4 years (range, 11 to 88 years). There were 308 left and 346 right knees imaged. The most common clinical diagnosis in these 654 patients was meniscal tear (42.8%). A total of 5 patients had a proximal tibiofibular ganglion cyst detected on MRI, yielding a prevalence of 0.76% (95% confidence interval [CI] = 0.1% to 1.4%). These cysts ranged in size from 1.0 to 2.8 cm in maximum diameter. Three were found in men and 2 in women. The mean age of these patients was 47.6 years (range, 42 to 54 years). The most common preimaging diagnosis in these patients was a medial meniscal tear (in 3 of 5).

Conclusions: This study is the first to provide data on the prevalence of proximal tibiofibular ganglion cysts in a population of patients with knee pain significant enough to warrant MRI. Over half of the patients found to have proximal tibiofibular ganglion cysts had no symptoms or signs attributable to them.