Repetitive strain injury is not a specific condition
Repetitive strain injury is not a specific condition; it is made up of a group of different, specific conditions. These specific conditions are often related in some way so if a patient has one, they are very likely to suffer with another to.
Below is a list of a few of the more specific conditions that make up repetitive strain injury.
Tenosynovitis
Carpal Tunnel Syndrome
There is a nerve located in the wrist called the median nerve, the nerve runs through the carpal tunnel, which is a canal in the wrist that is surrounded by bones, there are also a number of tendons that run through the canal with the median nerve.
When the median nerve becomes compressed it can cause pain, numbness, weakness in the hand, tingling sensations and swelling. The name carpal tunnel syndrome comes from the carpal tunnel the median nerve runs through.
Cubital Tunnel Syndrome
This condition is very similar to the carpal tunnel syndrome but affects the elbow region of the arm. The ulnar nerve passes through the cubital channel (where the syndrome gets its name from) and travels over the elbow. Sometimes the ulnar nerve can become compressed by repetitive use, which causes severe pain and possible swelling.
DeQuervains Syndrome
A sheath that holds the two tendons controlling the thumb causes this syndrome. The two tendons control the muscles of the thumb, which moves the thumb into a straight position. When this movement is carried out continuously the sheath known as the synovial sheath becomes inflamed and swells, this compresses the two tendons causing pain and restricting the movement of the thumb.
Intersection Syndrome
This affects the inner forearm (the side that the thumb is found) and is caused by two muscles that cross over two tendons. When a twisting motion is carried out repetitively, like wringing out a cloth this can cause the tendons to be compressed by the muscles and make them rub against each other causing pain in the area and shooting pains up the forearm and down into the thumb.
Trigger Finger
Trigger finger is a condition that makes it painful to straighten or bend your fingers or thumb; it can also affect one or more fingers at once.
This condition is caused by the tendons running to the fingers not being able to slide freely through the sheath they are held, this can happen for two reasons, the first is repetitive use, which can cause the tendon to become swollen compressing itself or secondly, a nodule can form on the tendon which can rub against the sheath.
Pain in the nerves and blood vessel around the brachial plexus and axilla (between the base of the neck and the armpit) is caused, unlike most conditions that make repetitive strain injury, by compression of blood vessels. The subclavian artery and vein are the two blood vessels that most commonly get compressed to cause this condition, although the vertebral artery and the nerves that make up the brachial plexus can also become compressed.
Compression is caused by the body’s position due to repetitive movements. The condition is called thoracic outlet syndrome because it is found in the thoracic region of the body.