Compression syndromes of peripheral nerves develop as a result of prolonged irritation and pressure of the nerve stem by surrounding tissues at the passage of the nerve through bone and ligament tunnels. Nerves are very sensitive to injuries. In places characterised with high movability (joints) or exposed to frequent though small injuries (e.g. elbow), nerves are protected in the above mentioned bone and ligament tunnels. These areas are characterised with limited free space and any diseases causing reduction of that space result in nerve compression (e.g. hypothyroidism), degenerative changes (work with equipment causing vibrations), previous injuries (acute – fractures, or resulting from overloading – lifting of heavy weights or repeating the same movements, such as using the computer mouse, for many hours). Clinical symptoms of nerve compression are similar in all compression syndromes, with the only differences being: location of the pain, sensation disorder intensity and degree of weakening other muscle group functions.
Ailments usually begin with fingers getting numb during the given activity. If the activity is stopped, the Patient shakes the hand or foot, the problem disappears. As the disease intensifies, the symptoms become more acute. This means night pains with finger sensation disorders within the scope which the nerve is responsible for, compression pain in the area where nerve compression occurs, muscle atrophy and weakening. In advanced stages, pain may propagate onto nearby limb elements. The Patient may even experience shoulder pain in case of the carpal tunnel compression syndrome.
Most frequently, compression syndromes concern upper limb nerves, mainly the median nerve at the carpal tunnel level and the ulnar nerve in the ulnar nerve sulcus at the elbow level, as well as the ulnar nerve at the wrist level in Guyon’s tunnel.
Main differences concerning the compression syndromes:
- compression of the median nerve causes numbness of the 1st, 2nd and 3rd fingers and thenar eminence atrophy;
- compression of the ulnar nerve causes numbness of the 4th and 5th fingers and hypothenar muscle atrophy;
- in case of long term and severe compression at the elbow level, another symptom is weakening of the muscles responsible for finger bending and forearm pains.
Examination by the doctor and detailed interview concerning development of the disease are the most important. Additional examinations allowing confirmation of the diagnosis include:
- EMG (electromyography) – nerve and muscle transmission examination identifying the place of weakened transmission of electric impulses in the nerve;
- USG of the area of suspected compression – allows determination of nerve swelling and the place of compression by surrounding tissues.
Peripheral nerve compression syndromes ought to be differentiated from root syndromes resulting from compression of nerve roots at the level of spine in connection with discopathy, degenerative changes and chronic nervous tissue diseases causing slower transmission of electrical impulses through the nerve. Differential diagnostics uses magnetic resonance examinations of the respective spine section as well as EMG examination of nerve roots.
- Elimination of reasons causing the disease:
- change of habits,
- change of the manner of working and spending free time (e.g. cycling supports development of the median nerve compression syndrome in the wrist tunnel),
- diagnostics and possible treatment of diseases causing compression or overgrowth of connective tissue (e.g. hypothyroidism),
- proper treatment of injuries nearby passing nerves (anatomic reduction of fractures and proper rehabilitation).
- Physical therapy in connection with anti-inflammatory medicines administered generally and locally.
- Surgical treatment involving removal of tissues causing nerve compression.
The surgery is performed in the hypoemic area obtained by placement of a compression band over the arm.
The treatment involves uncovering of the median nerve at the wrist height and partial removal of tissues causing pressure on the nerve.
Performance of the surgery does not guarantee elimination of the ailments experienced so far. The final treatment effect is closely related with observing the doctor’s recommendations and undergoing the full cycle of rehabilitation treatments, adapted to the individual needs of each Patient.
Side effects and complications
Performance of any medical intervention involves the risk of side or adverse effects.
These may include body temperature increase after the treatment, temperature increase in the operated area, reddening of the joint skin and of the surgical wound area including swelling and separation of the wound, which is connected with a prolonged healing process.
The most frequent complication is pain of the wrist, which persists for several weeks and hinders rehabilitation. In terms of frequency, the second complication is swelling of the wrist or, occasionally, of the whole limb. In some cases, a thick scar develops in the surgical wound area and the Patient may experience pain and sensation disorders there. Damage to vessels or nerves in the operated limb is a rare complication. Surgical wound infection is very rare.
So-called late complications include development of scar changes within the surgical wound and deep within hand tissues. These may cause pain and limited movability of the wrist. In extreme cases, if combined with negligence of recommendations to spare the elbow, return of the full scope of symptoms of the disease being the reason underlying the surgery may occur.
The risk of complications is several times higher in emaciated or obese Patients.
- pharmacotherapy: medicines improving nerve functioning, analgesic and anti-inflammatory medicines administered generally (pills, suppositories, intramuscular injections) or locally in the form of ointments, gels and local injections;
- physical therapy – iontophoresis;
- rehabilitation – kinesiotherapy, analgesic and anti-inflammatory physical therapy;
- electrostimulation of the damaged nerve.