Intraneural Ganglion Cyst of the Ulnar Nerve at the Elbow Masquerading as a Malignant Peripheral Nerve Sheath Tumor

Multimodality imaging review of ulnar nerve pathologies

The ulnar nerve is the second most commonly entrapped nerve after the median nerve. Although clinical evaluation and electrodiagnostic studies remain widely used for the evaluation of ulnar neuropathy, advancements in imaging have led to increased utilization of these newer / better imaging techniques in the overall management of ulnar neuropathy. Specifically, high-resolution ultrasonography of peripheral nerves as well as MRI has become quite useful in evaluating the ulnar nerve in order to better guide treatment. The caliber and fascicular pattern identified in the normal ulnar nerves are important distinguishing features from ulnar nerve pathology. The cubital tunnel within the elbow and Guyon's canal within the wrist are important sites to evaluate with respect to ulnar nerve compression. Both acute and chronic conditions resulting in deformity, trauma as well as inflammatory conditions may predispose certain patients to ulnar neuropathy. Granulomatous diseases as well as both neurogenic and non-neurogenic tumors can also potentially result in ulnar neuropathy. Tumors around the ulnar nerve can also lead to mass effect on the nerve, particularly in tight spaces like the aforementioned canals. Although high-resolution ultrasonography is a useful modality initially, particularly as it can be helpful for dynamic evaluation, MRI remains most reliable due to its higher resolution. Newer imaging techniques like sonoelastography and microneurography, as well as nerve-specific contrast agents, are currently being investigated for their usefulness and are not routinely being used currently.

Peripheral nerve tumors of the hand: Clinical features, diagnosis, and treatment

The majority of the tumors arising from the peripheral nerves of the hand are relatively benign. However, a tumor diagnosed as malignant peripheral nerve sheath tumor (MPNST) has destructive consequences. Clinical signs and symptoms are usually caused by direct and indirect effects of the tumor, such as nerve invasion or compression and infiltration of surrounding tissues. Definitive diagnosis is made by tumor biopsy. Complete surgical removal with maximum reservation of residual neurologic function is the most appropriate intervention for most symptomatic benign peripheral nerve tumors (PNTs) of the hand; however, MPNSTs require surgical resection with a sufficiently wide margin or even amputation to improve prognosis. In this article, we review the clinical presentation and radiographic features, summarize the evidence for an accurate diagnosis, and discuss the available treatment options for PNTs of the hand.

Current and future applications of ultrasound imaging in peripheral nerve disorders

Neuromuscular ultrasound (NMUS) is a rapidly evolving technique used in neuromuscular medicine to provide complimentary information to standard electrodiagnostic studies. NMUS provides a dynamic, real time assessment of anatomy which can alter both diagnostic and management pathways in peripheral nerve disorders. This review describes the current and future techniques used in NMUS and details the applications and developments in the diagnosis and monitoring of compressive, hereditary, immune-mediated and axonal peripheral nerve disorders, and motor neuron diseases. Technological advances have allowed the increased utilisation of ultrasound for management of peripheral nerve disorders; however, several practical considerations need to be taken into account to facilitate the widespread uptake of this technique.

Ulnar intraneural cysts as a cause of cubital tunnel syndrome: presentation of a case and review of the literature

INTRODUCTION

Intraneural cysts usually involve the common peroneal nerve, and in many cases, they are causing symptoms due to neural compression. It is hypothesized that these cysts originate from the adjacent joints while articular pathology is a major contributing factor for the formation of these lesions. Although ulnar nerve is the second most commonly affected nerve, these lesions usually develop distally at the Guyon tunnel, so cubital tunnel syndrome due to epineural cysts is very rare. In such cases, elaborate preoperative work-up is mandatory and surgical treatment should follow certain well-defined principles.

CASE DESCRIPTION

A 60-year-old female patient presented with complaints of pain along the medial side of her elbow, forearm and hand and a tingling sensation in the same distribution for the past 2 months. The patient had sustained an injury 15 years ago, and a distal humerus fracture was diagnosed at that time. Radiological signs of posttraumatic elbow arthritis were evident at the initial evaluation. The patient was diagnosed with cubital tunnel syndrome which was further confirmed by nerve conduction studies, and she underwent surgical decompression of the nerve. During surgery, intraneural cysts were identified and addressed by excision, while dissection of the articular branch of the nerve was also performed. Pain and numbness subsided shortly after surgery, while the patient remained free of symptoms until the last follow-up.

The cubital tunnel syndrome caused by intraneural ganglion cyst of the ulnar nerve at the elbow: a case report

Background

Cubital tunnel syndrome is common nerve compression syndrome among peripheral nerve compression diseases. However, the syndrome caused by intraneural ganglion cysts has been rarely reported. Medical approaches, like ultrasound-guided aspiration and open surgical treatment remain to be discussed.

Case presentation

A 57-year-old woman presented with occasional pain, numbness and paralysis in her left hand and a palpable, painless mass in the ulnar side of her left elbow. Ultrasound-guided aspiration of the mass was performed to decompress the ulnar nerve. The patient experienced an evident release of pain in her hand, but symptoms of numbness and paralysis recurred 3 months later which greatly bothered the patient’s daily life. After evaluation, we had to perform an open surgery to excise the cyst. External neurolysis and anterior subcutaneous transposition were done. The patient was followed up for 2 years, and she made a complete recovery with no functional limitation.

Conclusions

The symptoms caused by intraneural ganglion cyst can be alleviated by accurate puncture. But puncture may be not complete and symptoms could recur. Complete external neurolysis can be counted as a complete and reliable treatment. Therefore, early diagnosis, careful preoperative imaging assessment and full decompression can be expected to receive a good rehabilitation.