Overview of ulnar neuritis
Ulnar neuritis is a non-specific inflammatory lesion of the ulnar nerve with motor sensory deficits innervated by the ulnar nerve. The pathological changes are demyelination of ulnar nerve fibers and infiltration of inflammatory cells, and in severe cases, axonal degeneration may occur. The main clinical manifestations are impaired dysfunction of the ulnar nerve and obvious pressure points at the ulnar nerve travel. The prognosis of this disease depends on the severity of the lesion, most of them can be completely restored to normal, and a few of them may have sequelae.
Causes
The etiology of ulnar neuritis is categorized as primary, secondary and delayed, mostly due to ulnar nerve entrapment. The cause of ulnar neuritis is mostly related to elbow fracture and its residual deformity or abnormal bone growth. For example, elbow valgus deformity after epicondylar humerus fracture; poor repositioning or scarring of medial epicondylar fracture; ossified myositis of the elbow joint, etc. can cause damage to the ulnar nerve due to its traction or compression.
Symptoms
Early clinical manifestations of nerve dysfunction in one and a half fingers of the little finger and ring finger, high rate of disability, early symptoms are not obvious and easy to ignore, in severe cases, myasthenia gravis combined with claw shape and disability, hand muscle atrophy and muscle weakness. Clinical manifestations include ulnar nerve damage dysfunction and ulnar nerve travel with obvious pressure points. The manifestations of ulnar nerve damage are weakness of the ulnar wrist flexors, deep flexors of the 4th and 5th fingers, and all muscle groups within the hand, and decreased or absent sensation in one and a half fingers on the ulnar side. Among the muscles in the hand, the main weakness and atrophy of the interosseous muscle and the palmar interosseous muscle lead to the loss of the fullness of the palmar interosseous shape, and the fingers can’t be joined together, the metacarpophalangeal joints of the ring finger and the little finger are in the state of mild dorsiflexion, the fingers can’t be completely straightened and separated to the sides, and the fingers can’t complete the action of flexing the palmar fingers and stretching the interphalangeal joints. The interphalangeal joints of the thumb were in a semi-flexed state due to the weakness of the thumb retractor. Due to the weakness of the interosseous muscles, the proximal phalangeal joint of the extensor digitorum totalis is hyperextended, while the flexor digitorum flexes the terminal joint, which is characterized as a “claw shaped hand”. Skin sensory deficits are limited to one and a half fingers on the ulnar side of the hand and the area between the fissures.
Examination
1. Physical examination: tenderness point after the medial epicondyle or the medial epicondyle.
(1) Claw deformity of the fingers, most noticeable in the ring and little finger;
(2) Loss of cutaneous sensation on the ulnar half of the hand, with deep sensory loss limited to the little finger;
(3) External booth at the little finger, unable to retract internally;
(4) Flexion of the metacarpophalangeal joints at 90° and inability to straighten the interphalangeal joints at the same time indicate paralysis of the interosseous muscles and the earthworm muscles;
(5) Gradual atrophy of the interosseous and piriformis muscles, with the first dorsal interosseous muscle being the most obvious;
(6) Inability to retract the fingers internally, and reduced or absent abduction paper-clamping force, most obvious in the ring and little finger.
2. Electromyography: Electromyography of the ulnar nerve suggests that the ulnar nerve is neurologically impaired, which can clarify whether there is ulnar nerve entrapment and the location of ulnar nerve lesions.
Diagnosis
The onset of ulnar neuritis is slow, and in the early stage, patients only feel mild numbness and pain on the ulnar side of the hand. In the middle and late stages, there will be muscle atrophy of the hand, weakness in splitting and joining fingers, difficulty in flexing the wrist to the ulnar side, weakness, loss of sensation in the ulnar side of the hand and one and a half fingers on the ulnar side, and in severe cases, “claw hand” can appear. If the patient has symptoms of ulnar nerve injury, physical examination reveals motor and sensory injuries in the ulnar nerve innervation area, and electromyography is used to localize the injuries, the diagnosis of ulnar neuritis can basically be clarified.
Treatment
If this disease is found late or not treated in time, it is difficult to restore normal function even if the compression or pulling factors are lifted. Patients should seek medical treatment in time after symptoms appear, early diagnosis and treatment, and avoid surgery to the maximum extent possible. Mainly for the cause of the treatment. Prioritize non-surgical treatment, closely observe the changes of the condition, once found that the treatment is ineffective or there is a negative change in the condition and then proceed to surgical treatment. Surgery is not only more expensive, but also requires patients to suffer from post-operative pain and may leave some functional disorders after surgery.
(i) Non-surgical treatment: Treatment with neuroprotective and nutritional drugs, usually two weeks for a cycle, and continue for another cycle if there is a therapeutic effect. Usually conservative treatment will have a very obvious effect after one month. Intramuscular injections of vitamin B1 and vitamin B12 are given. activities are also reduced.
(ii) Surgical treatment:
1. Ulnar nerve advancement and intraneural release surgery
It is the most commonly used treatment. The ulnar nerve should be relocated as soon as it begins to show symptoms of injury, and its function will recover better. After transposition, it is also possible to cut the outer membrane of the nerve and do inter-bundle release of the nerve under the microscope, which is more favorable to the recovery of nerve function.
2. Osteotomy of elbow inversion
In the early stage of ulnar neuritis, when combined with obvious elbow exostosis, it is feasible to perform inversion osteotomy. In this way, not only the pulling factor of ulnar nerve can be lifted, but also the deformity of elbow valgus can be corrected.
3. Tendon transfer
If the symptoms of ulnar nerve injury have lasted for several years or more, and it is impossible to recover the nerve function, tendon transfer can be considered to rebuild part of the function.
Questions you may be concerned about
What is the treatment for ulnar neuritis?
The treatments for ulnar neuritis include medication, physical therapy and surgery.
1. Medication: It can be treated by oral or intramuscular injection of relevant vitamins, such as vitamin B1, B12, methylcobalamin, and so on.
2. Physical therapy: symptoms can be relieved by acupuncture, tuina, hot compresses and so on.
3. Surgery: If the patient’s symptoms cannot be relieved through medication or physical therapy, surgical treatments such as nerve relaxation can be performed, which is beneficial to the recovery of the condition. In severe cases, tendon displacement surgery can also be performed.
Patients with ulnar neuritis should go to the hospital in time, under the treatment of the doctor for standardized treatment, so as not to delay the condition. The use of medication should be in accordance with the doctor’s instructions.