Introduction:
Neuropraxia is peripheral nerve injury causing motor and sensory loss by affecting the nerve conduction in the affected area. Neuropraxia is a grade 1 peripheral nerve injury that blocks the injured nerve and prevents the transmission of signals (electrical). The affected site remains out of communication from the rest of the body until the nerve block is cleared and the signal transmission is resumed. The condition may be caused due to any injury from accidents, sports, surgical trauma, etc. Typically these mild peripheral injuries get to recover on their own, but if the pain is persistent, medical and surgical intervention may be needed. Therefore, a person should take necessary safety measures to prevent such incidents and wear protective gear such as helmets, knee pads, and other equipment.
What Are the Various Types of Neuropraxia?
The various types of neuropraxia occur at different sites of injury. These include
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Brachial Plexus Neuropraxia: In this shoulder or branchial nerves are damaged due to an injury. These branchial nerves carry impulses or signals from the spinal cord to the arms and hands and cause symptoms in one arm.
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Axillary Neuropraxia: Axillary nerve damage caused by an injury causes symptoms in the arms, shoulders, and hands. These nerves carry impulses from the shoulder joint and arm muscles.
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Sural Nerve Neuropraxia: Sural nerves are present between the calf, heels, foot, and brain to transmit impulses. Therefore, damage to the sural nerve causes neuropraxia in these regions, and symptoms occur mainly in the foot and ankle.
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Radial Nerve Neuropraxia: Radial nerve injury causes the symptoms in hand and back of the arm. The radial nerve carries signals in these regions, which are affected by neuropraxia, and symptoms are felt in the hand's index and middle fingers, thumb, and back.
What Are the Causes of Neuropraxia?
Neuropraxia is mainly caused due to ischemia (low blood supply in the tissues) and compression. Also, inflammation can be a cause of neurapraxia. Neuropraxia is caused by various reasons, such as:
Surgical Complications:
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Poor padding of body supports.
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Poor body positioning during surgeries.
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Anesthesia-related complications cause chemical nerve damage or blood supply cut off by narrowing the vessels.
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Complications caused by ACL (anterior cruciate ligament reconstruction) may also occur during hip replacement surgeries.
Traumatic Neuropraxia:
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Dislocation.
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Bone fractures.
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Injuries and tears to tendons and ligaments.
Other Causes:
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Giving birth.
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Endodontic procedures.
What Are the Symptoms of Neuropraxia?
Neuropraxia symptoms may not occur soon after the injury but can appear after a few weeks. It may be due to inflammation-causing nerve damage by compressing the nerve. The symptoms of neuropraxia caused by blood loss are short-term, whereas those caused by compression are long-lasting and form a neural blockage. Symptoms of neuropraxia are as follows.
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Numbness.
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Pain.
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Weakness.
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Tingling.
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Burning.
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Stinging.
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Loss of motor abilities.
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Loss of sensations.
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Touch sensitivity.
How Is Neuropraxia Diagnosed?
The healthcare provider diagnoses the neuropraxia by physical examination of the patient. The doctor also advises various laboratory blood tests, such as kidney function, complete blood count, liver function, blood glucose, vitamin B12 levels, thyroid function, and erythrocyte sedimentation rate.
In addition, a needle EMG (electromyogram) study is performed on the patient starting from day two or three up to day six and is done routinely every six weeks. The test helps identify nerve and muscle health during an injury and indicates any defects in nerve-to-muscle impulse transmission, nerve damage, or muscle dysfunction.
Also, peripheral nerves and muscles are examined through an ultrasound to identify the nerve continuity. Computed tomography (CT scans) also help identify the unreduced bone fractures that may cause compression of the nerves and muscles in the affected body area.
The doctor also recommends magnetic resonance imaging (MRI) of the pelvis and lumbar spine to identify the source of nerve compression causing neuropathy. MRI is usually done immediately after any postoperative and traumatic injuries.
What Is the Treatment for Neuropraxia?
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The doctor usually manages neuropraxia by using conservative treatment methods. The doctor mainly recommends limb support, physical rehabilitation, splints, avoiding physical activities, and avoiding neuropathic medications for pain, such as antidepressants, analgesics, corticosteroids, anticonvulsants, etc.
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Hematoma nerve compressions are immediately decompressed, and in case of compressions due to trauma or fractures, surgical decompression is needed.
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Fasciotomy may also be required in case of compartment syndrome.
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If there is no recovery in a patient after three to six months, surgical treatment may be required to manage the scar tissue that might be preventing the recovery. The doctor performs nerve decompression and transposition to treat the patient.
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Physical rehabilitation is done by managing pain and providing psychological support to the patient. Pain management is very challenging in peripheral nerve damage cases as dysesthesia and burning sensation is produced along the nerve distribution. In such cases, the doctor may prescribe anticonvulsants, tricyclic antidepressants, baclofen, and some short-term treatment with NSAIDs (nonsteroidal anti-inflammatory drugs), opioids, and Tramadol.
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In addition, the doctor advises the patients to take precautions to avoid repetitive injury.
What Is the Differential Diagnosis for Neuropraxia?
Neuropraxia condition of the nerves can resemble various muscles and nerve illnesses. Therefore, the diagnosis should be made cautiously by the doctor. These differential diagnoses include:
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Axonotmesis.
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Inflammatory neuritis.
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Muscle diseases.
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Diabetic neuropathy.
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Paraneoplastic neuropathy.
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Upper neuron disease.
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Radiculopathy.
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Neurotmesis.
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Spinal cord trauma.
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Infectious neuropathy, such as leprosy.
What Are the Complications Associated With Neuropraxia?
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Psychological issues.
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Long-term neuropathic pain, weakness, and numbness.
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Muscle atrophy due to improper diagnosis.
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Economic losses.
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Tissue scars at the injury sites.
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Inflammation.
Conclusion:
Patients suffering from neuropraxia usually recover within two to three months after an injury. The prognosis for the condition is very good; however, neuropraxia from major injuries can cause permanent damage in approximately 30 percent of cases. Neuropraxia is a very mild form of peripheral nerve injury and may arise from paresthesias, transient weakness, and nerve conduction blockage at the injury site. Therefore, a person suffering from neuropraxia should take all the necessary precautions advised by the doctor and keep the healthcare provider informed and updated about their recovery process and healing.