Post-Operative Assessment of Ulnar Nerve Tension Using Shear-Wave Elastography

Background: Ulnar nerve compression at the elbow level is the second-most common entrapment neuropathy. The aim of this study was to use shear-wave elastography for the quantification of ulnar nerve elasticity in patients after ulnar nerve decompression with anterior transposition and in the contralateral non-operative side. Method: Eleven patients with confirmed diagnosis and ulnar nerve decompression with anterior transposition were included and examinations were performed on an AixplorerTM ultrasound system (Supersonic Imagine, Aix-en-Provence, France). Results: We observed significant differences at 0-degree (p < 0.001), 45-degree (p < 0.05), 90-degree (p < 0.01) and 120-degree (p < 0.001) elbow flexion in the shear elastic modulus of the ulnar nerve in the operative and non-operative sides. There were no statistically significant differences between the elasticity values of the ulnar nerve after transposition at 0-degree elbow flexion and in the non-operative side at 120-degree elbow flexion (p = 0.39), or in the ulnar nerve after transposition at 120-degree elbow flexion and in the non-operative side at 0-degree elbow flexion (p = 0.09). Conclusion: Shear-wave elastography has the potential to be used postoperatively as a method for assessing nerve tension noninvasively by the estimation of mechanical properties, such as the shear elastic modulus.

Compression neuropathies

Nerve compression disorders affect nerve trunks, particularly in the upper extremity where carpal tunnel syndrome (median nerve compression at the wrist) is the most common and ulnar nerve compression the second most common disorder. Compression affects the various components of the nerve trunk, including the intraneural blood vessels, the Schwann cells, the axons, and the connective tissue components. It results in sensory and motor dysfunction, and sometimes pain. Risk factors for nerve compression disorders are known and may predict surgical outcome. A careful clinical examination should always be done, sometimes complemented with appropriate electrophysiology and magnetic resonance imaging for diagnosis. If conservative treatment is not appropriate, or fails, simple decompression is generally the primary treatment, but problems may persist. The presence of other neuropathies should be considered.

Revision Peripheral Nerve Surgery of the Upper Extremity

Peripheral nerve injuries of the upper extremity can result from a wide array of etiologies, with the two most common being compression neuropathy and traumatic injuries. These types of injuries are common and can be psychologically, functionally, and financially devastating to the patient. A detailed preoperative evaluation is imperative for appropriate management. Traumatic injuries can typically be treated with local burial techniques, targeted muscle reinnervation, and regenerative peripheral nerve interfaces. Median nerve compression is frequently managed with complete release of the antebrachial fascia/transverse carpal ligament and/or use of flap coverage such as the hypothenar fat pad flap and local muscle flaps. Ulnar nerve compression is commonly managed via submuscular transposition, subcutaneous transposition, neurolysis, and nerve wrapping. In this review, we discuss the preoperative evaluation, surgical techniques, and advantages and disadvantages of each treatment modality for patients with compressive and traumatic upper extremity nerve injuries.

Pigmented Villo Nodular Synovitis as an Atypical Cause of Deep Motor Branch Neuropathy

Introduction: Compression of the ulnar nerve in Guyon’s canal results in ulnar tunnel syndrome (UTS). The patient may present with sensory and motor deficits (zone 1), motor deficit (zone 2), or sensory deficit (zone 3). The most common causes of UTS include ganglion cysts, idiopathic ulnar nerve compression, occupational pressure neuritis (repetitive compression), prolonged compression, hook of hamate fractures, and arterial thrombus or aneurysm. Case Report: We report an atypical cause of UTS involving pigmented villonodular synovitis (PVNS) with a review of the literature. Surgical decompression of the ulnar nerve at Guyon’s canal has resulted in resolving motor weakness and improved interosseous strength at latest follow-up. Conclusion: The most common causes of UTS are ganglion, occupational neuritis, prolonged compression, and ulnar artery thrombi/aneurysms. However, other more rare causes such as PVNS should be considered in the appropriate patient. Keywords: Neuropathy, ulnar nerve, ulnar tunnel.

An unusual presentation of low ulnar nerve palsy: a case report

<p>Ulnar nerve compression at the Guyon’s canal is an uncommon cause of ulnar nerve neuropathy. Among various reasons like trauma, non-union of hook of hamate, anomalous muscle anatomy, thrombosis of the ulnar artery or pseudoaneurysm, ganglion is a common lesion which can compress the ulnar nerve at this site. With proper history taking and physical examination consisting of assessing motor functions and sensation of the hand, a clinician can localize the site of the lesion. Ultrasound is cheap and non-invasive technique which helps to localize the site of lesion and can suggest the nature of the lesion. Surgical decompression of the canal and careful removal of the lesion can help ameliorate the symptoms. In our study the patient presented with sudden onset weakness of the right hand and symptoms progressing within one and half month. With proper muscle charting, sensory examination and with the help of sonography, the main culprit was localized to Guyon’s canal. Excision of the lesion helped in recovery of hand function within 5 months.</p>