Repetitive motion of the hands, arms, and shoulders can lead over time to numbness, tingling, pain, and weakness in the arms and hands. These injuries are known by a collection of terms: Repetitive Stress Injury (RSI), Collective Trauma Syndromes, and by the most common term: Carpal Tunnel Syndrome.
While Carpal Tunnel Syndrome is a specific diagnosis, the term is sometimes inaccurately used to describe any RSI that affects the hands.
What is Carpal Tunnel Syndrome?
CTS is a condition where the median nerve is compressed in the wrist at the carpal tunnel. The Carpal Tunnel is the space between the flexor retinaculum, a halter of connective tissues that protects and stabilizes the tendons of the forearms flexors and blood vessels and nerves, and the small bones of the wrist, which are collectively called the carpal (scaphoid, lunate, triquetral, pisiform, trapesium, trapezoid, capitate, hamate) bones. The Carpal Tunnel is small, and when the tissues that pass through it become inflamed, that inflammation can impinge the median nerve.
Area of hand innervated by median nerve.
As seen in the photograph, the median nerve powers the lateral half of the hand. Numbness, pain, and muscle weakness can sometimes be ascribed to impingement of the median nerve in the wrist.
When the median nerve is impinged in the carpal tunnel, symptoms can make it very difficult to have good hand function.
Other RSI Injuries
The hand can have symptoms in the other parts of the hand not innervated by the median nerve. For instance the medial half of the hand - that is the other half of the fourth finger, the fifth finger, and the palm not powered by the median nerve - are innervated by the ulnar nerve, and the muscles that move those two fingers and help bring the pinky finger against the thumb in opposition can exhibit similar symptoms to carpal tunnel syndrome. The difference, though, is that the ulnar nerve does not pass through the carpal tunnel, and treatment of carpal tunnel syndrome will not have an effect. The ulnar nerve can be impinged in the wrist in the ulnar canal, or further up in the elbow at the cubital fossa.
The radial nerve innervates the forearm extensors, as well as the nerve endings in the dorsal (back) of the hand. The radial nerve also innervates the triceps in the upper arm, so impingement in the shoulder and neck can have an effect on the functioning of the upper arm and elbow as well.
The Brachial Plexus
The brachial plexus is the bundle of nerves that emerges from the sides of the vertebra in the neck upper chest between the vertebra named C4, C5, C6, C7 in the neck, and T1 in the chest. The nerves pass through the anterior and medial scalene muscles in the neck before passing down between the first rib and the clavicle, and from there down into the arm The scalene muscles are often tight from holding the head forward and still for long periods of time of sitting at a computer. This tightness can cause the first rib to pull up against the clavicle, which can impinge the brachial plexus and subclavian artery. When these nerves and arteries are impinged, they can cause some of the pain symptoms farther down the line of the nerves. So it’s a good idea to get the entire nerve pathway checked out when there are pain and numbness in the arm.
How can massage help?
Massage can help by creating relaxation in the muscles along the route of the nerves of the arm. In a study by the Touch Research Institute at the University of Miami School of Medicine, researchers found that massage was able to bring a significant reduction in pain and other symptoms of carpal tunnel syndrome. Skilled massage can bring about relief from the numbness, pain, and tingling associated with carpal tunnel syndrome and other repetitive stress injuries.
A trained massage therapist can test of various nerve entrapment locations and craft the necessary treatment plan to release the muscle tension, and free the nerve.