Secondary Posterior Interosseous Nerve Lesions Associated With Humeral Fractures

Introduction: Radial nerve lesions associated with humeral shaft fractures are the most common traumatic nerve lesions observed with long bone fractures. Secondary indirect posterior interosseous nerve (PIN) lesions can be associated with traumatic radial nerve palsy. The aim of this study was to identify cases of traumatic double-site radial nerve involvement through ultrasound (US). Methods: Patients with traumatic radial nerve lesions referred to our laboratory from January 2010 to January 2014 were evaluated. Results: Of the 35 patients, 18 had US evidence of a radial nerve lesion at the fracture site associated with secondary PIN involvement at the arcade of Frohse. Conclusions: Multiple-site nerve lesions are difficult to demonstrate through electrodiagnostic tests. In our case series, half of the patients with traumatic radial nerve damage had US evidence of PIN injury. Prospective studies with follow-up are needed to determine the clinical and prognostic relevance of this finding and the best therapeutic approach.