【Radial Canal Syndrome】
After people reach middle age, radial canal entrapment occurs due to trauma, tumors, fractures, dislocation, arthritis, scars, neuritis, iatrogenic injury, etc., resulting in radial canal compression. Nerve pain, muscle weakening disease.
[Cause]
Radial tunnel syndrome is common in the dominant hand, and it often occurs due to manual work and repeated forearm rotation. Specific reasons:
1. Trauma
Forearm injuries caused by trauma can form scars and adhesions at the radial nerve easily compressed parts, causing nerve entrapment.
2. Tumor
ganglion cyst and lipoma within the supinator myotube.
3. Fractures and dislocations
Radial head dislocation and Monteggia fractures can easily cause radial nerve damage .
4. Rheumatoid Arthritis
Rheumatoid lesions can thicken the synovium, destroy the humeral-radial joint capsule in the late stage, cause dislocation of the radial head, and damage nerves.
5. Local scars
After inflammation and trauma, local scars gradually appear, which can cause nerve entrapment.
6. Viral neuritis
Most people with symptoms that have occurred for 3 months will have a history of "cold" and viral infection, resulting in hyperplasia of connective tissue inside and outside the nerves.
7. Iatrogenic injury
mainly involves the injection of local sealing drugs, traditional Chinese medicine, etc., which can cause scarring around the nerves and nerve damage .
[Clinical manifestations]
1. Pain
The main clinical manifestations of pain are dull pain, pain on the outside of the elbow, radiating along the nerve, aggravation of symptoms with activity, obvious pain at night, and severe pain that wakes up at night. Venous stasis, the pain worsens when using tourniquet .
2. Weakened muscle strength
Sluggishness and numbness are less common. Weakened finger and thumb extensor muscles are often caused by pain. Muscle atrophy may also occur in the later stages.
[Examination]
1, Radial Canal Compression Test
A small slidable bundle can be touched about 5cm away from the lateral epicondyle of the humerus . This is the place where the posterior interosseous nerve passes through the strong and narrow arch, and there is tenderness.
2. Middle finger extension test
Extending the middle finger tightens the extensor carpi radialis brevis fascia and compresses the posterior interosseous nerve. Inspection method: When the elbow is in the pronated position and the forearm is fully extended, the patient's middle finger is extended against resistance. If there is pain in the radial canal area, the test is positive. Local occlusive treatment helps in differential diagnosis.
3.X-ray examination
can identify and rule out dislocation of the radial head and Monteggia fracture.
[Differential diagnosis]
1. Radial tunnel syndrome needs to be differentiated from lateral epicondylitis .
2. Radial canal syndrome and posterior interosseous nerve entrapment syndrome
First, compression of the radial nerve at the elbow can cause two entrapment symptoms, namely radial canal syndrome and posterior interosseous nerve entrapment syndrome.
The second reason is that the causes of the two are similar, the compression sites are similar, and there is no obvious difference in pathology. Clinically, they are only distinguished by clinical manifestations, that is, radial canal syndrome is dominated by sensory impairment , and movement disorder is not obvious. Posterior interosseous nerve entrapment syndrome is dominated by movement disorders.
【How to deal with it? 】
1. Conservative treatment
Early conservative treatment is to fix the forearm in the wrist extension, elbow flexion, and forearm supination positions to minimize the tension of the radial canal and achieve the purpose of reducing nerve entrapment.
2, partial sealing, once a week, 2 to 3 consecutive times as a course of treatment; at the same time, oral administration of B vitamins and methimazole.
3. Surgical treatment. If conservative treatment is ineffective and there is weakness or inability to extend the fingers or intractable pain in the elbow, release surgery can be performed. For advanced patients whose extensor muscles have obviously atrophied for more than one and a half years, direct tendon transposition surgery can be considered. .
4. Under the guidance of musculoskeletal ultrasound, precise hyperplasia, adhesion and compression positioning is performed, nerves are released, and local sealing treatment is assisted, which has immediate results.
Dr. Zhou Biqiang has been practicing medicine for 40 years. He specializes in spine-related diseases. He holds consultations every Friday afternoon and Saturday morning at the outpatient clinic of Shenzhen Second People’s Hospital in the neuropathy MDT and spine pain MDT departments.
