Clinical features of wrist drop caused by compressive radial neuropathy and its anatomical considerations.
OBJECTIVE
Posture-induced radial neuropathy, known as Saturday night palsy, occurs because of compression of the radial nerve. The clinical symptoms of radial neuropathy are similar to stroke or a herniated cervical disk, which makes it difficult to diagnose and sometimes leads to inappropriate evaluations. The purpose of our study was to establish the clinical characteristics and diagnostic assessment of compressive radial neuropathy.


METHODS
Retrospectively, we reviewed neurophysiologic studies on 25 patients diagnosed with radial nerve palsy, who experienced wrist drop after maintaining a certain posture for an extended period. The neurologic presentations, clinical prognosis, and electrophysiology of the patients were obtained from medical records.


RESULTS
Subjects were 19 males and 6 females. The median age at diagnosis was 46 years. The right arm was affected in 13 patients and the left arm in 12 patients. The condition was induced by sleeping with the arms hanging over the armrest of a chair because of drunkenness, sleeping while bending the arm under the pillow, during drinking, and unknown. The most common clinical presentation was a wrist drop and paresthesia on the dorsum of the 1st to 3rd fingers. Improvement began after a mean of 2.4 weeks. Electrophysiologic evaluation was performed after 2 weeks that revealed delayed nerve conduction velocity in all patients.


CONCLUSIONS
Wrist drop is an entrapment syndrome that has a good prognosis within several weeks. Awareness of its clinical characteristics and diagnostic assessment methods may help clinicians make diagnosis of radial neuropathy and exclude irrelevant evaluations.
Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea.
Bo Ram
BR
Han
Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea.
Yong Jun
YJ
Cho
Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea.
Jin Seo
JS
Yang
Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea.
Suk Hyung
SH
Kang
Department of Neurosurgery, Chuncheon Sacred Heart Hospital, College of Medicine, Hallym University, Chuncheon, Korea.
Hyuk Jai
HJ
Choi
Arcade of Frohse; Entrapment syndrome; Posterior interosseous nerve; Radial nerve; Superficial radial nerve