Clinical Characteristics of Peroneal Nerve Palsy by Posture

OBJECTIVE: Posture induced common peroneal nerve (CPN) palsy is usually produced during the prolonged squatting or habitual leg crossing while seated, especially in Asian culture and is manifested by the onset of foot drop. Because of its similarity to discogenic foot drop, patients may be diagnosed with a lumbar disc disorder, and in some patients, surgeons may perform unnecessary examinations and even spine surgery. The purpose of our study is to establish the clinical characteristics and diagnostic assessment of posture induced CPN palsy. METHODS: From June 2008 to June 2012, a retrospective study was performed on 26 patients diagnosed with peroneal nerve palsy in neurophysiologic study among patients experiencing foot drop after maintaining a certain posture for a long time. RESULTS: The inducing postures were squatting (14 patients), sitting cross-legged (6 patients), lying down (4 patients), walking and driving. The mean prolonged neural injury time was 124.2 minutes. The most common clinical presentation was foot drop and the most affected sensory area was dorsum of the foot with tingling sensation (14 patients), numbness (8 patients), and burning sensation (4 patients). The clinical improvement began after a mean 6 weeks, which is not related to neural injury times. Electrophysiology evaluation was performed after 2 weeks later and showed delayed CPN nerve conduction study (NCS) in 24 patients and deep peroneal nerve in 2 patients. CONCLUSION: We suggest that an awareness of these clinical characteristics and diagnostic assessment methods may help clinicians make a diagnosis of posture induced CPN palsy and preclude unnecessary studies or inappropriate treatment in foot drop patients.

Bilateral Visual Loss as a Sole Manifestation Complicating Carotid Cavernous Fistula

Visual loss is one of the ocular symptoms resulting from a carotid cavernous fistula (CCF), but has rarely been reported as the sole manifestation in CCF. Visual impairment is known to be associated with a poor outcome unless timely intervention is employed. Herein, the authors report a patient with bilateral rapid progressing visual loss as a sole manifestation in CCF. Vision was successfully restored by transarterial embolization. The authors discuss the necessity of urgent fistula obliteration in patients with visual loss.