Carpal tunnel syndrome is a condition where compression occurs in the carpal tunnel of the median nerve. It can be provoked by compression or injury.
The concept of tunnel syndrome is not universal for the wrist area; this condition can also manifest itself in other anatomical areas, where the nerves run rather superficially and close to the bone structures simultaneously. However, the syndrome in question manifests itself in the form of a decrease or lack of sensitivity in the thumb, index, middle, and half of the ring finger and impaired motor function in them.
Carpal tunnel syndrome is a common pathology and occurs in 1-3% of the population, mainly in people, an occupation associated with fine, monotonous motor skills. Half of all those suffering from this syndrome are people whose type of employment is associated with using a computer. Also, this disease can be considered an occupational pathology in musicians, tailors, office workers, etc. Hand pain occurs in the active working-age population at an already mature age (40-60 years) and in 105 cases at a younger age. Scientists have concluded that active PC users have a 15% higher risk of developing the syndrome, especially women.
Causes of hand pain
The median nerve of the hand passes through the tunnel formed by the transverse ligament and the carpal bones. Compression of the nerve in the carpal tunnel can be provoked by:
- Traumatic injuries of the hand. Bruises, dislocations, sprains, and fractures can provoke swelling of the ligaments and muscles or even displace the wrist bones. All this can compress the nerve in the carpal tunnel and disrupt its function. With proper treatment, all these processes are reversible. Still, if you do not provide assistance in time and correctly, then the contractures of muscles and ligaments and deformation of the bones can already be irreversible.
- Arthrosis, arthritis, and other pathological articular processes of various etiology and genesis. Edema and inflammatory reactions caused by these pathologies, up to tissue necrosis, can also cause nerve compression. With the permanent course of inflammation and the progression of degenerative-dystrophic processes, the articular surfaces of the wrist lose their properties and wear out, resulting in deformation and compression of the nerve in the canal by bone structures that cause hand pain.
- Inflammation of the tendons or tendovaginitis. Inflammation can be septic (caused by microorganisms) and aseptic (caused by exertion, hypothermia, etc.). Such diseases can provoke septic inflammation as purulent wounds of the hand, including panaritium, the improper technique of taking blood from a finger, etc. Non-infectious inflammation can be caused by chronic traumatic stress, for example, frequent monotonous hand motility, static load on it, temperature trauma.
- Diseases that lead to water retention in the body can cause swelling of the limbs and, as a result, lead to an increase in soft tissue volume and compression of the median nerve and hand pain. Moreover, violation of the water-electrolyte composition can cause: pregnancy, taking hormonal contraceptives, menopause, kidney disease, etc.
- Rarely, but there are tumors of the nervous tissue and the median nerve in particular. Most of these are benign neoplasms (schwannomas, neurofibromas, perineuromas), but malignant ones arise from the nerve sheaths. With its growth, the tumor compresses the nerve, which leads to its damage and hand pain.
- Diabetes. Under the influence of the enzyme protein kinase C, sorbitol and fructose accumulated during the disease begin to break down in nerve tissues. Because of this, and due to a violation of the trophism of neurons and their processes, aseptic inflammation of the nerves and surrounding tissues occurs. Edema increases, which in turn leads to compression of the nerves, including the median.
- Acromegaly. As a result of the prolonged and intensive growth of a person suffering from acromegaly, disproportionate growth of bone and soft tissues occurs. The median nerve can become pinched in a narrower carpal tunnel due to increased bone volume and lumen narrowing.
- Congenital malformations. The transverse wrist ligament can be thickened from birth, and there is also weak production of tendon lubrication. One of the predisposition factors to carpal tunnel syndrome can serve as an anatomical feature of the structure, the so-called “square wrist.”
Carpal tunnel symptoms
- Feeling of numbness in the fingers. The syndrome in question, as a rule, develops gradually, and the lesion manifests itself one-sided. The pathological process occurs in that limb, which is the leading one, in the right-handed – the right hand, and in the left-handers – the left. Thus, the development of carpal tunnel syndrome occurs gradually. However, a two-way process can also be observed with diseases of the endocrine system, pregnancy, etc.
- Paresthesia symptom. Manifested as tingling sensations and loss of sensitivity in the fingers. They appear in the morning after waking up and disappear within a few hours. But over time, these manifestations become more stable and more intense and can already become permanent; this can disrupt the normal function of the limb, strength, dexterity, etc. The patient has to change hands when performing actions to rest the affected limb. Special inconveniences are caused by manipulations requiring static tension of the limb.
- Pain. With the manifestation of the disease, such symptoms may appear as a burning sensation and tingling sensation in hand; this is quickly eliminated by lowering the limb and shaking it. The blood flow in the arm resumes, and the painful sensations disappear; this occurs during sleep due to the static position of the hand or during monotonous work performed by the limb. Pain is not common in any specific joint but is a common issue. With the progression of the disease, pain can affect the fingers and the entire hand and arm up to the elbow joint, which often complicates the diagnosis. In addition, the patient cannot carry out their duties because pain can occur during the daytime.
- Loss of agility and strength. Over time, if the disease is not treated, the limb begins to lose strength and dexterity in movements. It is difficult for the patient to hold objects in their hands, especially small ones; they seem to fall out spontaneously. Besides, the ability to perform fine motor skills is lost (grabbing small things, opposing the thumb, etc.).
- Decreased sensitivity. Over time, the patient may begin to notice that they do not distinguish the temperature of objects well, cease to feel touches or even pricks. There is a painful burning sensation in the hand, numbness.
- Amyotrophy. With advanced forms of the syndrome, atrophy of the musculo-ligamentous apparatus of the arm may develop, the muscles and ligaments lose strength and decrease in size. Over time, the hand deforms and takes on a shape resembling a monkey’s paw.
- Skin discoloration. Because when the innervation of the hand is disturbed, the nutrition of the skin cells also occurs; the color of the skin changes, they become lighter and unevenly colored.
Surgical treatment of hand pain
For six months or more, if conservative therapy does not give the desired effect, then it makes sense to think about the surgical resolution of the disease. The main task of the surgical intervention is to eliminate the pressure on the median nerve by expanding the carpal tunnel.
Most operations are performed under local anesthesia.
The following methods are used:
- The carpal ligament is cut through open access through an incision in the region of the carpal canal.
- Endoscopic surgery. There are two types of endoscopic intervention- two incisions and one incision. In the first case, an endoscope is inserted into one incision, and an instrument is inserted into the second for dissection of the ligament. In the second case, both tools are inserted in one hole.
A plaster cast is applied to the arm at the end of the surgery to immobilize the limb. After removing the plaster, a course of physiotherapy and physiotherapy is carried out. As a rule, complete restoration of hand function occurs within six months. After recovery, the patient can return to work, provided that the protective regime is observed not to provoke a relapse of the disease.
In the modern world, where computer technologies have already been introduced everywhere, the pathology we are considering is becoming more common. Timely and qualified assistance and prevention in the event of carpal tunnel syndrome allow complete and sufficient remission to be achieved.