Dorsal digital nerves of ulnar nerve

Dorsal digital nerves of the ulnar nerve are a group of nerves in the hand that are branches of the ulnar nerve. They are responsible for providing sensory innervation to the skin of the medial side of the hand, including the little finger and the adjacent half of the ring finger. These nerves play a crucial role in the sensory and motor functions of the hand, contributing to the complex movements and sensory feedback necessary for tasks ranging from simple grasping to fine motor skills.

Anatomy

The ulnar nerve is one of the three main nerves of the forearm, the others being the median nerve and the radial nerve. It originates from the medial cord of the brachial plexus, carrying fibers from the C8 and T1 nerve roots. As it travels down the arm, it enters the hand via the ulnar canal, also known as Guyon's canal, at the wrist.

Upon reaching the hand, the ulnar nerve divides into several branches, including the dorsal digital nerves. These nerves specifically branch out to supply the dorsal aspects of the little finger and the adjacent side of the ring finger. Unlike the palmar digital nerves, which also stem from the ulnar nerve and provide sensation to the palmar aspect of these fingers, the dorsal digital nerves are primarily involved in sensing touch, pain, and temperature on the back of the hand.

Function

The primary function of the dorsal digital nerves of the ulnar nerve is sensory. They provide the brain with information about tactile sensations, such as touch, pressure, and vibration, as well as thermal sensations, including warmth and cold. This sensory feedback is essential for protective reflexes and for the fine-tuned movements of the fingers and hand.

Clinical Significance

Damage or compression to the ulnar nerve can lead to sensory deficits and motor dysfunction in the areas supplied by its branches, including those innervated by the dorsal digital nerves. Conditions such as ulnar nerve entrapment or Guyon's canal syndrome can result in numbness, tingling, or weakness in the little finger and part of the ring finger, affecting grip strength and dexterity.

Diagnosis of ulnar nerve pathology may involve clinical examination, nerve conduction studies, and imaging techniques such as MRI or ultrasound. Treatment options vary depending on the cause and severity of the condition but may include physical therapy, splinting, or surgical intervention to relieve pressure on the nerve.

See Also

• Ulnar nerve
• Guyon's canal syndrome
• Brachial plexus
• Median nerve
• Radial nerve