In contrast to electrophysiologic tests, high-resolution sonography can show the exact location, extent, and type of a postoperative peripheral nerve lesion and the concurrent disease of surrounding tissues. Because the latter can often be the causative agent for the development of a lesion or the lack of improvement with conservative treatment, sonography yields important information that may not be obtained with other diagnostic modalities.

Sonography allows radiologists to visualize neural and extraneural pathology and to define the exact level and extent of lesions. Thus, it may be a valuable adjunct in the decision of whether surgical intervention is necessary.

The deep branch of the radial nerve appears enlarged in patients with supinator syndrome.

The effect of extracorporeal shock wave (ESW) therapy on skin flap survival and growth factor expression was investigated in a rat model using epigastric skin flap. Treatment and control groups each contained 20 animals. ESW effectively enhanced epigastric skin flap survival by significant reduction of areas of necrotic zones. At day 7 after the operation, necrotic zones of 4.2% were found in the ESW-treated group compared with 18.3% in the control group ( P < 0.01). Concomitantly, in tissue samples adjacent to the necrosis areas, increased vascular endothelial growth factor expression was observed in the ESW-treated animals (median 84.5%, range 57.4 to 94.5%) compared with the control group (median 46.7%, range 29.1 to 93.1%; P < 0.1). However, for expression of basic fibroblast growth factor, no difference was found between the two groups. The authors conclude that the success of the shock wave treatment may partly be due to modulation of growth factor expression.