Carpal tunnel syndrome (often abbreviated to CTS) is a nerve neuropathy in the carpal tunnel (see picture). The carpal tunnel is a tunnel about 2 cm wide in the wrist; it is a tight tunnel where nine flexor tendons plus the median nerve that runs through it, forming an arch. The main purpose of the nerve and tendons are to provide function and movement, as well as sensation and feelings to some of the fingers in the hand. Fundamentally, it is the repeated compression of the median nerve at the point in the carpal tunnel, that leads to the development of CTS (simple flexing of the wrist can cause and give rise to this).
The compression of the median nerve causes muscle weakness (pinch and grip strength commonly goes down) as well as the loss of sensation in the distribution points of the nerve. Most of the patients with carpal tunnel syndrome that we treat complain of numbness and tingling sensations that comes and goes, in the thumb, index finger, middle finger and partially in the ring finger. The tingling sensations becomes more prevalent when the affected wrist is flexed for a sustained period, or repetitively, so activities that may aggravate it is: sleeping (where wrists are often flexed unconsciously), working etc.
Long term carpal tunnel syndrome damage causes irreversible nerve damage to the median nerve, meaning the numbness and tingling feeling will then become a near-permanent problem, shrinkage of the affect muscles which causes weaknesses in pinch and grasp of the affected fingers.
CTS is classified as a form of repetitive strain injury, which is caused or aggravated by activities that require a repetitive motion, and the three main clusters of people that I often see with this complaints are:
The three groups of people mentioned above engage in activities that require constant repetitive activities. Take the housewives for example, cleaning the house would require the repeated motion of squeezing and wringing wet cloths, which can prove quite resistive. So is ironing clothes, etc. For the new mothers, they often have to care for the newborns with enthusiasms, often overusing their wrists and bodies. For the office workers, the keyboard crunching, stapling, writing etc contributes to the factor.
Now don't get me wrong, I'm not suggesting that one doesn't clean the house, have babies or work. Whilst it is true that activities mentioned by the roles mentioned above is the one that contributes to carpal tunnel syndrome, it is only half the story.
The other half lies in another 2 factors: first, genetics. Some people are more predisposed to it. Secondly, which is the more common factor, is not resting when their bodies are demanding for it. Now again, I'm not suggesting that workers all stop working etc, but what studies suggest is that for every 30 minutes of work, one should take a 1-2 minutes rest-stretch, to rest the muscles, and stretch to encourage blood circulation and relief of muscles and structures.
Some common conditions that contributes to CTS includes arthritis, obesity, trauma, diabetes and hypothyroidism. Other causes are grouped into internal factors that cause pressure from inside the tunnel, as well as external factors can cause pressure from outside the tunnel, such as ganglions and vascular malformations.
Work related causes
This is a sensitive and even controversial topic in regards to CTS and work relationship. A patient with carpal tunnel syndrome typically is entitled to medical leave as well as compensation (in US, each case costs companies about USD 30,000.00 in time/opportunity costs as well as medical costs). From a hand therapist perspective, patients with CTS don't want CTS; it hinders not only work and productivity, but the effects WILL spillover into other parts of their personal lives, as activities such as using keys, taking money, picking up coins, fastening belts and bra straps, brushing teeth, everything that requires the use of the hands, will be affected.
What we do is to provide talks to increase awareness and prevention of repetitive strain injuries (RSIs) such as carpal tunnel syndrome, as well as other RSIs, that we can prevent them from occurring. This is a win-win situation for both employees and employers in terms of productivity and quality of life being less at risk for the development of CTS in the workplace.
Simple treatments for CTS includes use of night splints as well as corticosteroid injections, but the quickest relief management is a surgical intervention where the orthopedic or hands surgeon will do a simple carpal tunnel release of cutting the transverse carpal ligament. This provides immediate relief, and one can be assured that the problem of carpal tunnel compression syndrome will never come back in the operated hand.
Where to next?