Ultrasonographic demonstration of intraneural neovascularization after penetrating nerve injury.

INTRODUCTION: Hypervascularization of nerves has been shown to be a pathological sign in some peripheral nerve disorders, but has not been investigated in nerve trauma. METHODS: An observational cohort study was performed of the intraneural blood flow of 30 patients (34 nerves) with penetrating nerve injuries, before or after nerve reconstruction. All patients underwent electrophysiological assessment, and B-mode and color Doppler ultrasonography. RESULTS: Intraneural hypervascularization proximal to the site of injury was found in all nerves, which was typically marked and had a longitudinal extension of several centimeters. In 6 nerves, some blood flow was also present within the injury site or immediately distal to the injury. No correlation was found between the degree of vascularization and age, size of the scar / neuroma, or degree of reinnervation. DISCUSSION: Neovascularization of nerves proximal to injury sites appears to be an essential element of nerve regeneration after penetrating nerve injuries. Muscle Nerve 57: 994-999, 2018.

Ultrasonography in neuralgic amyotrophy: Sensitivity, spectrum of findings, and clinical correlations.

INTRODUCTION: The aim of this study was to assess the value of ultrasonography in neuralgic amyotrophy. METHODS: Fifty-three patients with 70 affected nerves were examined with high-resolution ultrasound. RESULTS: The most commonly affected nerve was the anterior interosseous (23%). Ultrasonographic abnormalities in the affected nerves, rather than in the brachial plexus, were observed, with an overall sensitivity of 74%. Findings included the swelling of the nerve/fascicle with or without incomplete/complete constriction and rotational phenomena (nerve torsion and fascicular entwinement). A significant difference was found among the categories of ultrasonographic findings with respect to clinical outcome (P = 0.01). In nerves with complete constriction and rotational phenomena, reinnervation was absent or negligible, indicating surgery was warranted. DISCUSSION: Ultrasonography may be used as a diagnostic aid in neuralgic amyotrophy, which was hitherto a clinical and electrophysiological diagnosis, and may also help in identifying potential surgical candidates. Muscle Nerve 56: 1054-1062, 2017.

Ultrasonographic identification of nerve pathology in neuralgic amyotrophy: Enlargement, constriction, fascicular entwinement, and torsion.

INTRODUCTION: The aim of this study was to characterize the ultrasonographic findings on nerves in neuralgic amyotrophy. METHODS: Fourteen patients with neuralgic amyotrophy were examined using high-resolution ultrasound. RESULTS: Four types of abnormalities were found: (1) focal or diffuse nerve/fascicle enlargement (57%); (2) incomplete nerve constriction (36%); (3) complete nerve constriction with torsion (50%; hourglass-like appearance); and (4) fascicular entwinement (28%). Torsions were confirmed intraoperatively and were seen on the radial nerve in 85% of patients. A significant correlation was found between no spontaneous recovery of nerve function and constriction/torsion/fascicular entwinement (P = 0.007). CONCLUSION: Ultrasonographic nerve pathology in neuralgic amyotrophy varies in order of severity from nerve enlargement to constriction to nerve torsion, with treatment ranging from conservative to surgical. We postulate that the constriction caused by inflammation is the precursor of torsion and that development of nerve torsion is facilitated by the rotational movements of limbs.