Axonotmesis is defined as nerve injury characterized by disruption of myelin sheath and axon, but with preservation of the connective tissue fragments that effects in degeneration of the axon distal to the injury site and regeneration of the axon is spontaneous and of good quality.
- Axonotmesis nerve harm is usually sustained by a severe contusion and also known as a bruise, or a crushing injury.
- However, it will also occur with a stretching injury.
- symptoms will range from pain to dysfunction, including paralysis.
- Paralysis occur in the motor, sensory and autonomic systems.
- Motor paralysis presents as inability to move muscle or muscle groups.
- Sensory system paralysis will disrupts the transportation of electrochemical signals of the nerves. Autonomic system paralysis will prevents from regulatory functions of the nerves which aids in the body’s abilities to adapt to changes in the environment.
In addition to general examination, tests that are conducted for systemic diseases such as glucose, kidney functions.
- A nerve conduction test is done to find out the extent of the injury.
- Electromyography is another diagnostic test utilized in axonotmesis.
- Nerve conduction velocity test:NCV study will show the loss of nerve conduction in the distal segment (3 to 4 days after injury). According to NCV study, in axonotmesis there will be an absence of distal sensory-motor responses.
Electromyography (EMG)is a diagnostic test that will understands the physiological of muscles and thereby assess health conditions . Electromyography involves inserting a needle electrode through skin into the muscle. This electorde detects the electrical activity in the muscles and nerves controlling the muscles. A patient is questioned to flex or contract the muscles so that the response of the muscle to nerve stimuli is observed. An electromyograph will help to detect and measure electric potential that is generated by the contracting muscles. Another indicators to the correct functioning of the muscles and their corresponding nerves are size, duration and frequency of electric signals received from them. EMG is conducted along with nerve conduction velocity test . The EMG test is used to detect any possible weakness or impaired muscle strength due to neurological problems. EMG test will helps in differentiating between a muscle and nerve disorder. The muscle feel tender after the EMG test with localised bruising is done .
Treatment of axonotmesis includes:
- Physical therapy. Physical therapy aims include:
- Pain relief
- Maintain range of motion
- Reducing muscular atrophy
- Patient education
- Use of assistive devices (Orthotic needs)
- Surgical treatment (For example, in cases of surrounding scar tissue)
The prognosis is good in terms of its improvement. Rate of improvement will depends on the distance from the site of harm and with axonal regeneration will occurs at 1 to 4 mm per day. Peripheral nerves regeneration will take respective months.