The Efficacy of Ultrasound for Visualizing Radial Nerve Lesions with Coexistent Plate Fixation of Humeral Shaft Fractures

Pragmatic use of ultrasound in plaster room

X-ray represent gold standard to check reduction of fractures and dislocations. Sometimes plaster room is not equipped with C-arm or similar devices. Practical and focused use of ultrasound in plaster room cannot replace X-ray but may be a useful tool especially in tricky situations. We report three emblematic cases and we carry out a review of the literature.

The role of imaging in focal neuropathies

Electrodiagnostic testing (EDX) has been the diagnostic tool of choice in peripheral nerve disease for many years, but in recent years, peripheral nerve imaging has been used ever more frequently in daily clinical practice. Nerve ultrasound and magnetic resonance (MR) neurography are able to visualize nerve structures reliably. These techniques can aid in localizing nerve pathology and can reveal significant anatomical abnormalities underlying nerve pathology that may have been otherwise undetected by EDX. As such, nerve ultrasound and MR neurography can significantly improve diagnostic accuracy and can have a significant effect on treatment strategy. In this chapter, the basic principles and recent developments of these techniques will be discussed, as well as their potential application in several types of peripheral nerve disease, such as carpal tunnel syndrome (CTS), ulnar neuropathy at the elbow (UNE), radial neuropathy, brachial and lumbosacral plexopathy, neuralgic amyotrophy (NA), fibular, tibial, sciatic, femoral neuropathy, meralgia paresthetica, peripheral nerve trauma, tumors, and inflammatory neuropathies.

Optimal timing of needle electromyography to diagnose lesion severity in traumatic radial nerve injury

INTRODUCTION/AIMS

In patients with traumatic radial nerve injury (RNI), the chance of spontaneous recovery must be balanced against the benefits of early surgical reconstruction. We aimed to explore the time-specific value of needle electromyography (NEMG) to diagnose nerve lesion severity.

METHODS

In this retrospective diagnostic accuracy study at Leiden Nerve Center, patients at least 12 years of age with RNI caused by fractures or fracture treatment were included. The sensitivity and specificity of the patients' first NEMG examination were assessed, stratified by the timing after the nerve injury. The absence of motor unit potentials (MUPs) in muscles distal to the nerve lesion was considered a positive test result. Lesion severity was dichotomized to moderate injury (spontaneous Medical Research Council grade ≥3 recovery) or severe injury (poor spontaneous recovery or surgical confirmation of a mainly neurotmetic lesion).

RESULTS

Ninety-five patients were included in our study. The sensitivity of NEMG to detect severe RNI was 75.0% (3 of 4) in the fourth, 66.7% (2 of 3) in the fifth, and 66.7% (2 of 3) in the sixth month after the nerve injury. The specificity in the first to the sixth month was 0.0% (0 of 1), 50.0% (2 of 4), 77.3% (17 of 22), 95.5% (21 of 22), 95.8% (23 of 24), and 100.0% (12 of 12), respectively.

DISCUSSION

The specificity of NEMG is higher than 95% and therefore clinically relevant from the fourth month after the nerve injury onward. Absence of MUPs at this time can be considered an indication to plan nerve exploration. Moreover, the presence of MUPs on NEMG does not completely exclude the necessity for surgical reconstruction.

Radial nerve contrast fluoroscopy combined with ultrasound imaging for humeral shaft fracture

Ultrasonography is an alternative method for detecting the nerve tract in real-time. However, bones and soft tissues can encounter imaging difficulties because of the occasional blockade. Humeral shaft fracture can be addressed using several approaches, including open plate fixation and intramedullary nailing. Nevertheless, these methods are associated with a risk of radial nerve injury due to the presence of nerve tracts around the middle part of the humeral shaft. Here, we present a patient who underwent intramedullary nail fixation in the beach-chair position converted into open plate fixation in the prone position based on the radial nerve course on preoperative fluoroscopic evaluation. Combined fluoroscopy and ultrasonography of the fracture site facilitated the detection of anatomical structure disruption around the nerve and the safe completion of surgery. The nerve delineation technique with contrast-enhanced radiographic effects can prevent the risk of nerve injury.