A
tendon is a tough yet flexible band of fibrous tissue that attaches the muscles to the bones.

Specific tendons in the body are usually recognized to be
problematic. These tendons usually have an area known as a "watershed
zone," that has poor blood supply (with consequent poor access to oxygen)
which makes it more prone to injury with associated tissue damage and poor
healing process.

Tendonitis is most often the result of an overuse injury; in
case of the wrist joint, it’s the daily typing (inevitable) and household chores.
Symptoms of tendonitis include:

• ·        
  Tenderness directly over
  the tendon
• ·        
  Pain with movement of
  muscles and tendons
• ·        
  Swelling of the tendon

Another possibility is that of carpal tunnel syndrome (CTS), a
medical condition that causes numbness, pain, and discomfort in the hand. The
carpal tunnel is a space located in the center of the wrist through which a
major nerve (the median nerve) and nine tendons pass, from the forearm into the
hand. The roof of this tunnel is formed by a strong ligament called the
transverse carpal ligament.

Should the carpal tunnel swell up due to inflammation,
pressure will be exerted on the median nerve, which supplies most of the
feeling and movement to the fingers and thumb. When pressure becomes great
enough to compress the median nerve, CTS may occur.

In most cases, swelling in the carpal tunnel has no
identifiable cause. In healthy young women, we mostly think of repetitive hand
motion and activities that involve grasping, squeezing or clipping. CTS also
has a genetic component.

Diseases that may cause CTS include:

• ·        
  thyroid disease
• ·        
  fractures
• ·        
  arthritis

Also, fluid retention during pregnancy may produce CTS
symptoms, but these symptoms typically resolve after delivery.

Of course you need to have a doctor take a look at your
wrist to identify the exact cause and treat accordingly.