Peripnerve damage is common both in peacetime and during wartime. According to some statistics on war injuries from the Second World War, peripheral nerve injuries account for approximately 10% of the total number of external injuries, and about 60% of firearm-related fractures are accompanied by nerve injuries. The following is an introduction to the types and manifestations of peripheral nerve damage.

Radial nerve damage: Radial nerve damage is the most common among all the nerves in the body, and it often occurs as a complication of a mid-shaft humeral fracture. The main manifestations include loss of wrist extension and a characteristic wrist drop. There is also a loss of extension in the thumb and fingers, as well as complete loss of sensation between the first and second metacarpal bones.

Ulnar nerve damage: Injuries to the ulnar nerve result in an inability to flex the tips of the fourth and fifth fingers. There is also paralysis of the interosseous muscles, loss of abduction and adduction functions of the fingers, and atrophy and flattening of the hypothenar eminence. Complete loss of sensation in the little finger is also observed.

Sciatic nerve damage: This type of damage results in motor and sensory impairments. The anterior muscles of the thigh are paralyzed, leading to difficulty in lifting the leg during walking and an inability to dorsiflex the foot. Sensory disturbances include loss of sensation on the anterior and medial aspects of the lower leg. Atrophy of the quadriceps and prominence of the patella are also present. There is also a loss of the knee jerk reflex.

Pudendal nerve damage: When the pudendal nerve is completely severed, the clinical manifestations are similar to those of combined damage to the tibial and common peroneal nerves. There is no voluntary movement in the ankle and toe joints, the foot appears dorsiflexed and in a "foot drop" deformity, and the ankle joint sways with the affected limb during movement. Atrophy of the calf muscles, absence of the Achilles tendon reflex, weakness in knee flexion, and normal extension of the knee are also observed. Sensory disturbances are present except on the medial aspect of the lower leg, and may be perceived as decreased sensation due to compensatory innervation from other sensory nerves.

Proximal tibial nerve damage: typically presents with paralysis of the hamstring muscles and seldom involves the popliteal muscles and contiguous peripheral nerves. Additionally, there is often pain in the lower leg or the sole of the foot.

The types and manifestations of peripheral nerve damage also include damage to the perineal nerve: a characteristic deformity of the dropped foot occurs during walking as the patient lifts the foot high to prevent the toes from dragging on the ground. The foot and toes cannot dorsiflex or evert, and there is a loss of sensation on the outer side of the foot and the front of the little toe.

Brachial plexus nerve damage: primarily presents with motor and sensory impairments in a dermatomal distribution. Damage to the upper part of the brachial plexus results in a drooping entire upper limb, inward rotation of the upper arm, inability to externally rotate the arm, and inability to supinate or flex the forearm. The skin over the shoulder blade, upper arm, and outer side of the forearm has a narrow, lined area of sensory disturbance. Damage to the lower part of the brachial plexus results in claw-shaped atrophy of the small muscles of the hand, loss of sensation on the ulnar side of the hand and forearm, and sometimes the appearance of Horner's syndrome.

Axillary nerve damage: results in motor impairment with a decrease in the range of abduction of the shoulder joint. The skin of the deltoid area of the shoulder shows sensory disturbance. Atrophy of the deltoid muscle, loss of the rounded appearance of the shoulder, prominence of the shoulder blade, and the formation of a square shoulder pattern are observed.

Musculocutaneous nerve damage: after the musculocutaneous nerve emerges from the lateral cord, it traverses the coracobrachial muscle, runs between the biceps brachii and brachialis muscles, and then gives off branches to supply these three muscles. Its terminal branch, the lateral cutaneous nerve of the forearm, travels on the deep fascia of the arm and becomes the lateral cutaneous nerve of the forearm, which is distributed to the skin on the lateral aspect of the forearm. Damage to the musculocutaneous nerve results in sensory disturbances of the skin on the lateral aspect of the forearm, as well as motor disturbances of the biceps brachii, brachialis, and skin over the lateral aspect of the forearm.

Peripheral nerve damage also includes median nerve damage: loss of the ability to flex the first, second, and third fingers, loss of opposition of the thumb, atrophy of the thenar muscles, and the appearance of a simian hand deformity, as well as complete sensory loss in the fingertips.