Objective : Causes of nontraumatic posterior interosseous nerve (PIN) palsy include space-occupying lesions, constrictions of the PIN, and supinator syndrome. The purpose of this study was to identify these causes using Ultrasonography (US). Methods : We performed US in seven cases (seven elbows) with palsy and examined the PIN and surrounding structures. Results : We identified the three causes by the following US findings : 1) A space-occupying lesion in two elbows. Both were low-echoic and diagnosed as ganglion. In these two cases, the PIN was elevated by the lesion and compressed against the arcade of Frohse. 2) A diffusely swollen PIN with constrictions was found in three cases. 3) A PIN showing a reduction in caliber beneath and a swelling (pseudoneuroma) proximal to the arcade of Frohse, compatible with supinator syndrome was also identified. Conclusion : US is useful for the diagnosis of nontraumatic PIN palsy.

STUDY DESIGN: Case series. PURPOSE: The aim of this study was to describe translaminar microendoscopic herniotomy (TL-MEH) for cranially migrated lumbar disc herniations encroaching on the exiting nerve root in the preforaminal and foraminal zones and to report preliminary results of the procedure. OVERVIEW OF LITERATURE: Conventional interlaminar approaches for preforaminal and foraminal lumbar disc herniations result in extensive removal of the lamina and facet joint to remove disc fragments safely. More destructive approaches increase the risk of postoperative segmental instability. METHODS: TL-MEH is a minimally invasive procedure for herniotomy via the translaminar approach using a microendoscopic technique. TL-MEH was performed in seven patients with a cranially migrated lumbar disc herniation encroaching on the exiting nerve root. The disc fragments were located in the preforaminal zone in four patients, and in the preforaminal and foraminal zones in three. RESULTS: All patients experienced immediate relief from symptoms after surgery and satisfactory results at the final follow-up. Surgical complications, such as a dural tear, nerve injury, and surgical site infection, were not investigated. CONCLUSIONS: TL-MEH seemed to be an effective and safe alternative minimally invasive surgical option for patients with a cranially migrated lumbar disc herniation encroaching the exiting nerve root in the preforaminal and foraminal zones.
Follow-Up Studies ; Humans ; Zygapophyseal Joint