What is carpal tunnel syndrome? Treatment

What is carpal tunnel syndrome?

Carpal tunnel syndrome was first described by Paget in 1854. Detailed information on the clinical course and operative treatment methods was provided by Phalen in 1856. Carpal tunnel syndrome occurs when the median nerve is compressed at the level of the wrist and is the most common neuropathy of the upper extremity.

Anatomical structure

To correctly differentiate the diagnosis of carpal tunnel syndrome from other median nerve neuropathies, nerve root compression, and brachial plexus injury, it is necessary to know the anatomy of the carpal tunnel. The navicular (os. scaphoideum) and trapezoid (os. trapezoideum) bones are lateral to the carpal tunnel, the hook (os. hamatum) and pea (os. pisiforme) bones are medial, and the bottom of the traction that forms this tunnel is covered by the carpal ligament. The muscle tendon retainer covers this sulcus from above, thus forming a carpal tunnel.

Through this canal run the median nerve, the tendons of the four deep finger flexor muscles, the four superficial finger flexor muscles, and the tendon of the long thumb flexor. This nerve provides sensation to the thumb, index finger, middle finger, and half of the ring finger, and motor innervation of the middle forearm muscles.

There are many etiological causes of carpal tunnel syndrome. They are divided into six main groups:

• Causes that reduce carpal tunnel volume
• An increase in the size of structures passing through the canal or the occurrence of additional structures in the canal
• Neuropathic problems
• Inflammatory causes (tendon synovitis, etc.)
• Fluid imbalances
• External influences

Carpal tunnel syndrome mainly occurs in the 30-50 age groups. The ratio of women to men is 3:1. Carpal tunnel syndrome occurs in conjunction with systemic diseases such as diabetes mellitus, thyroid dysfunction, arterial hypertension, renal insufficiency, liver failure and etc. Carpal tunnel syndrome, which occurs during pregnancy, reduces its symptoms after delivery. Increased pressure inside the canal impairs the blood supply to the nerve and leads to a decrease in its function. In carpal tunnel syndrome, one complains of pain and numbness in the thumb, index, middle and radial part of the ring finger. In more severe cases, muscle atrophy and weakness occur.

How is the diagnosis made?

Diagnosis is made using historical data, physical examination tests, and electrophysiologic examination. In carpal tunnel syndrome, patients complain of stiffness, pain, especially pain that occurs at night and causes them to wake up. Also observed when buttoning and holding small objects. These signs increase when lifting the arm, driving, and talking on the phone (the patient has difficulty holding the telephone set to his ear).

Examination of the patient

Prerogative (complaint-based) tests are important in the diagnosis of carpal tunnel syndrome. These tests include:

Tinel’s test

The test result is considered positive if the ligament of the wrist, which is located at the level of the median nerve, becomes numb and electrified when it is struck.

Phalen’s test

In this test, both wrists are brought close to each other, brought into a 90-degree flexion position and the patient is asked to wait in this position for 60 seconds. Subsequently, a numbness sensation and other symptoms in the median nerve area will confirm the positive result of the test. Also note that the Phalen test produces fewer false positives than the Tinel test.

Durkan’s test

Another prerogative test that is performed by applying pressure to the carpal ligament for 30 seconds, while the patient holds the thumbs together. The occurrence of symptoms when the test is performed, indicates a positive result.

Electromyography

This is a test that measures the conduction of the median nerve. In patients who suffer from symptoms of carpal tunnel syndrome, the median nerve conduction decreases or stops completely.

Methods of treatment for carpal tunnel syndrome

The choice of treatment method depends on the severity of the condition. If the symptoms are mild and there are no signs of muscle atrophy, carpal tunnel syndrome treatment methods include steroid injections (initial injection into the nerve itself), nonsteroidal anti-inflammatory drugs (NSAIDs) and night orthoses. Physical therapy treatments are also used. These treatments are used in 10% of patients.

Steroid injections are also used as a method of differential diagnosis. Thus, with thoracic outlet syndrome, cervical intervertebral disc dislocation, tumor inside the carpal tunnel, osteophytes in the canal cavity and other causes, giving an injection will not alleviate the symptoms and will not be of significant benefit.

Methods of conservative treatment are effective for mild and moderate degrees of carpal tunnel syndrome, with severe degrees preferring methods of surgical treatment.

Methods of operative treatment are used when conservative treatment is ineffective and carpal tunnel syndrome is severe. The goal of this treatment method is to relax the carpal tunnel by making an incision on the carpal ligament. The most important goal of the surgical treatment is to completely relax the carpal tunnel ligament and reduce the pressure over the median nerve.

The figure shows the surgery for carpal tunnel syndrome