Guyon Canal Syndrome
Overview
Plain-Language Overview
Guyon Canal Syndrome is a condition that affects the ulnar nerve as it passes through a narrow passage in the wrist called the Guyon canal. This nerve controls some of the muscles in the hand and provides sensation to the ring and little fingers. When the nerve is compressed or irritated in this area, it can cause symptoms like numbness, tingling, and weakness in the affected fingers and hand. The condition mainly impacts the nervous system and hand function, making it difficult to perform tasks that require fine motor skills. It often results from repetitive wrist movements, trauma, or pressure on the wrist. Early recognition is important to prevent permanent nerve damage.
Clinical Definition
Guyon Canal Syndrome is a form of ulnar nerve entrapment neuropathy caused by compression of the ulnar nerve within the Guyon canal, a fibro-osseous tunnel at the wrist formed by the pisiform and hamate bones and the overlying ligament. The syndrome typically results from mechanical compression due to repetitive trauma, ganglion cysts, fractures, or prolonged pressure on the hypothenar eminence. This compression leads to sensory deficits in the ulnar nerve distribution of the hand and motor weakness of the intrinsic hand muscles innervated by the ulnar nerve, including the interossei and the medial two lumbricals. Clinically, it presents with paresthesias, claw hand deformity in advanced cases, and decreased grip strength. It is important to distinguish this syndrome from ulnar neuropathy at the elbow and other causes of hand neuropathies. Diagnosis and management focus on relieving the nerve compression to prevent irreversible nerve damage.