Overview.
Reflex somatic neuropathy is also known as somatic neuropathy and reflex sympathetic dystrophy. Reflex somatic neuropathy refers to a disease in which minor trauma to the hand or foot causes over-scaled flaccid paralysis or contracture of the limb on that side, accompanied by obvious autonomic dysfunction as the main clinical manifestation.
Etiology
It is thought to be caused by pathological irritation foci at minor traumatic injuries of the hands and feet such as stabbing, cutting, drug injection or acupuncture treatment, which stimulate the proprioceptive and deep nociceptive fibers.
Symptoms
1. Preferred site
The sympathetic nerve-rich median nerve and tibial nerve innervation area of the extremity after minor trauma.
2. Minor nerve injury with severe and widespread symptoms
For example, a minor puncture wound to one side of the fingers (toes) can lead to paralysis and muscle atrophy of the hand and forearm (foot and calf) on that side, or even the whole limb and the opposite limb. The dysfunction is extensive and extends far beyond the innervation area of the nerve.
3. Neurological symptoms
(1) Autonomic dysfunction is often seen within half an hour to 2-3 hours after the injury, with vasodilatory dysfunction as the main cause of obvious autonomic dysfunction. Often there is swelling of the limbs (in severe cases, blisters can appear), red, purple or marbled skin color, skin temperature drops, and in the later stage, there can be hyperpigmentation of the injured area which does not fade for a long time, and trophic changes of the finger (toe) nails. In severe cases, there may be bone decalcification and widening of joint space.
(2) Movement disorders are mostly manifested as severe limb paralysis or contracture. The former mostly appears in the early post-injury period, and most of them are incomplete (a few of them are complete) paralysis; tendon reflexes are mostly hyperactive, and some of them are reduced or disappeared; the latter appears later, or is transformed from paralysis. The cause of dyskinesia is due to reflex lesions of spinal cord dominance on the one hand, and motor pain in the limbs and joints on the other. Muscle atrophy appears earlier and can spread throughout the limb. Atrophied muscles show increased excitability to both mechanical and DC-induced electrical stimuli, but there is never an electrodegenerative response.
(3) Sensory disturbances Pain is predominant. The pain can be significantly reduced or only a slight pain or numbness when quiet and immobile. Objective examination mostly shows short-set hypesthesia, and a few may have hypersensitivity. In severe cases, there may be long-set hypesthesia, which may spread to the trunk near the proximal part of the limb.
Examination
Routine blood and biochemical tests and routine cerebrospinal fluid tests are mostly nonspecific. Cranial and limb imaging examinations are mostly normal, but have differential diagnostic significance.
Diagnosis
The diagnosis can often be made on the basis of the history of minor trauma to the hands and feet, and the extent and degree of clinical symptoms that are inconsistent with the trauma.
Differential diagnosis
1. Those with obvious autonomic symptoms
Erythema gangrenosum, cellulitis, contact allergic dermatitis and other diseases should be distinguished.
2. Those with obvious movement disorders
It should be differentiated from peripheral nerve trauma and hysteria.
3. Those with obvious pain symptoms
It should be distinguished from burning neuralgia, shoulder-hand syndrome and other diseases.
Complications
There are often irritability and instability, insomnia; pigmentation of the injury site, and in severe cases, there may be bone decalcification and widening of the joint space; myasthenia appears earlier and may spread to the whole limb.
Treatment
1. Reduce the sympathetic excitability and relieve the dominant lesion in the spinal cord segment.
(1) Closure therapy Cervical sympathetic ganglion and brachial plexus nerve closure can be tried for upper limb lesions, sacral epidural closure and lumbar sympathetic ganglion closure can be tried for lower limb lesions.
(2) Physical therapy can be supplemented with calcium iontophoresis and hyperthermia in the sympathetic nerve trunk and corresponding spinal cord segments.
(3) Ultraviolet radiation and oxygenated blood input therapy.
2. Surgical treatment
For cases that do not heal for a long time, if necessary, surgical exploration can be performed on the injured part to remove the scar and neuroma. Sympathetic nerve trunk cut off can also be tried.
3. Symptomatic treatment
(1) Anti-sympathetic hyperfunction drug treatment: Metoprolol, propranolol and other drugs can be given in appropriate amount when needed.
(2) Sleeping medications may be used alternately with meprobamate, triazolam, midazolam, diazepam, etc. to improve sleep and relieve mood.