What is Intersection Syndrome?
This is a condition of the wrist and forearm that is painful. It may disturb individuals who do wrist actions repeatedly, for instance downhill skiers, weight lifters, and any other sports that have repetitive motion. Shoveling and heavy raking may also trigger this syndrome.
Intersection Syndrome Symptoms
The friction on the tendons of the wrist with this syndrome causes swelling and pain in the tenosynovium which covered the tendons. This friction hinders the normally smooth sliding action. The individual might even be able to hear a squeaking noise as well as feel scraping as these tendons rub up against the muscles. This is referred to as crepitus. Individuals can have redness and swelling at the intersection point. Pain may migrate down to the thumb or upwards along the brink of the forearm.
Intersection Syndrome Causes
This condition is caused by the overuse of the wrist extensor tendons the tenosynovial lining which is slippery can develop inflammation from the continued rubbing against the two muscles of the thumb. As the tenosynovium becomes more inflamed and more irritated, it swells and then causes thickening. Pain will then be felt when the wrist is moved due to the swelling tendons rubbing against the muscles of the thumb.
Wrist extensor tendons execute like a bow that a violin player would use and the muscles of the thumb are like the violin strings. The wrist curls down and in with the tendons rubbing back and forth in contact against the muscles of the thumb. The friction continues to build up, much the same as the effect created by two sticks rubbing together. All of this leads to inflammation and irritation of the tenosynovium which covers the wrist extensor tendons.
These wrist extensor tendons become stressed by any actions creating the wrist to curl down and in, in the direction of the thumb. These movements of the wrist are particularly common in skiers who ski downhill as they plant the ski poles deep into the powdered snow. This same movement happens when pulling a rake against the ground. Some sports that may also stress the wrist extensor tendons include weight lifting, racket sports, rowing as well as canoeing.
Intersection Syndrome Treatment
Physicians normally can make the diagnosis of intersection syndrome while doing a physical exam. The majority of the time no distinctive tests are needed.
It is important to change or stop any activities that are causing these symptoms. Frequent breaks are needed when doing hand and thumb movements repeatedly. It is advised to avoid repetitive motions of the hand such as wringing, heavy grasping or twisting and turning movements of the wrist. Downhill skiers might get some relief by avoiding any heavy dragging and planting of the ski poles and by perhaps trying a shorter pole with a smaller basket diameter.
Keep the wrist in an alignment that is neutral. This means keep it in a straight line with the arm, with no bending down and in. Often the individual may be given a special thumb and forearm splint referred to as a “thumb-spica splint”. This keeps the lower thumb joints and the wrist from moving. By occasionally resting the wrist extensor tendons and the muscles of the thumb, it will allow this area to start the process of healing.
Drugs known as anti-inflammatory can help in managing the inflammation of the tenosynovium and relieving the symptom of pain. These medications can include OTC (over- the-counter) drugs such as aspirin as well as ibuprofen. Treatment with ice can also aid in decreasing swelling and relieve pain.
If the measures do not control the symptoms, the physician can suggest a cortisone injection. Cortisone is commonly used as an anti-inflammatory medication when early measures are not working. Injections of cortisone will normally control any inflammation especially during early stages of this syndrome. But, cortisone’s properties are only short-term, lasting from several weeks to several months.
The physician might also have the individual work with an occupational or physical therapist. The major focus of therapy is to eliminate or reduce the reason for the irritation to the thumb tendons. The therapist might check the workstation and see the way the individual does his/her work tasks. The therapist might also give suggestions about a healthy body alignment as well as wrist position, good exercises and tips on how to stop any future problems.
Rarely needed but sometimes necessary is surgery to treat Intersection syndrome. This is used only in those cases that are extremely difficult. The surgeon can remove some of the tenosynovium which has thickened around the tendons. This surgery is referred to as “tendon release”.
This procedure is usually done on an outpatient basis meaning that the individual does not have to spend time in the hospital. It is normally done under general anesthetic that puts the individual to sleep, or an anesthetic for a certain region of the body that blocks the nerves in that area of the body. Injections of drugs such as lidocaine are able to block nerves for several hours.
The individual might also get an axillary block that numbs the arm or a wrist block which only numbs the hand. It is even conceivable to do this surgery by only using an injection of lidocaine around the region where the incision will be made.
The 1st step is to make a very small incision over the area where the two (2) muscles cross over the two (2) tendons of the wrist.
The surgeon will then identify the tendons that are irritated and then separate and remove the tenosynovium that is inflamed from the tendons.
The incision is then stitched up and the hand is bound with a dressing.
A period of rehabilitation is needed after surgery. Symptoms and pain usually begin to recover immediately but there might be sensitivity in the area around the incision for some months.
The individual will possibly need to have sessions with an occupational or physical therapist for six (6) to eight (8) weeks. Full recovery usually takes several months.