The Effectiveness of Ultrasonography in the Diagnosis of Spontaneous Hourglasslike Constriction of Peripheral Nerve in the Upper Extremity

Objective: To investigate the ultrasonographic characteristics in hourglasslike constriction of peripheral nerve in the upper extremity and to evaluate the value of ultrasonography in the diagnosis.

Methods: Nineteen patients with hourglasslike constriction of peripheral nerve in the upper extremity underwent ultrasonography and the results were compared with surgery. The ultrasonographic characteristics, the accurate rate, and the relation between the ultrasonography and surgery were analyzed.

Results: There were 22 affected nerves involved in 19 patients, including 17 radial neuropathies, 4 median neuropathies, and 1 musculocutaneous neuropathy. The accuracy rate of ultrasonography in diagnosing hourglasslike constriction of upper limb nerve was 87.93%. Ultrasonography showed that the constriction sites were completely consistent with the operation. The ultrasonography characteristics of hourglasslike constriction of upper limb nerves were hourglasslike nerve incompleteness or complete constriction, and the nerves at both ends were thickened, and no compression structure was seen around. All lesions with complete constriction diagnosed by ultrasonography were treated with resection of the lesion with or without graft. In addition, 71.43% with incomplete constriction were treated with neurolysis, and 28.57% with resection of the lesion with direct repair.

Conclusions: Ultrasonography could be used as a routine noninvasive examination for hourglasslike constriction of upper limb nerves. Ultrasonography suggests that resection of the lesion rather than neurolysis should be considered in the treatment of complete constriction. For patients with clinical symptoms, ultrasonography showed local nerve enlargement but no constriction; clinicians should be prompted to explore carefully during operation to avoid missing nerve hourglasslike constriction.