Italian multicentre study of peroneal mononeuropathy at the fibular head: study design and preliminary results

BACKGROUND: The most common entrapment in the lower extremity is peroneal mononeuropathy (PM) at the fibular head. Several studies of this condition have been published but, until now, no wide multicenter clinical-neurophysiological studies on PM are available. In recent years, multicenter studies have been suggested; moreover it is commonly accepted that a multiperspective approach provides more comprehensive results. METHOD: The Italian CTS and other entrapments Study Group has designed a strict clinical and neurophysiological protocol to carry out a wide multicentre study on PM at the fibular head. In addition to traditional clinical-neurophysiological evaluation, the group has also adopted validated disability and patient-oriented measurements in order to obtain more comprehensive and reliable data about this entrapment. The study was designed: 1) to identify predisposing factors; 2) to better assess the clinical picture; 3) to evaluate relationships between etiological, clinical and neurophysiological findings; 4) to evaluate the natural evolution of the entrapment. Study design is described. FINDINGS: During the period from November 2002 to January 2004, 69 patients were enrolled consecutively in eleven Italian centres. Our preliminary data show that PM involves men more frequently than women (M:F = 3.9:1). With regard to the predisposing factors, PM is idiopathic (16%) or due to surgery (21.7%), prolonged posture (23.2%), weight loss (14.5%), external compression (5.8%), arthrogenic cyst at the fibula (1.4%), trauma (10.1%); it also occurred in bedridden patients (7.3%). Unexpectedly, peroneal nerve lesions were due not only to surgical operation close to the peroneal region, but were also associated with thoracic-abdominal surgery. Usually PM involves both terminal branches; patients complain of motor deficit in 99.5% of cases, sensory symptoms in 87.9% and pain in 19.7%. CONCLUSIONS: Our preliminary results provide some interesting information and confirm the usefulness of multicentre and multiperspective studies to standardise the approach to nerve entrapment.