OSTEOARTHRITIS OF THE THUMB

What Is Osteoarthritis (OA) ?

Osteoarthritis (OA) is due to the "wearing down" of the cartilage covering of the bones (see picture below) and is commonly seen in adults. OA can be caused by one or more of the following factors: genetic, metabolic, systematic and traumatic. There are two types of OA:

Primary - This is the most common type causing deformity, stiffness and occasional pain, however, little disability may occur for many years. Often inflammation of the joint can follow causing pain and cartilage breakdown.

Secondary - This type may occur in teens as well as adults, and cartilage wearing down is partly due to disorders from birth, trauma, inflammation and/or metabolic diseases.

The diagnosis of OA is made by the presence of bony enlargements around the involved joint. The below diagram displays a normal joint and a joint with breakdown of the cartilage.

Osteoarthritis Of The Thumb

The thumb is responsible for about 45% of hand function, and therefore, any inflammation, breakdown and/or pain has an impact on one's daily life. The wrist-thumb joint is most often affected.

Problems Encountered By Sufferers

Physical problems may include limited range of motion, stiffness due to inactivity (especially in the morning), enlarged and deformed joints, bony enlargements, muscle spasm, muscle wasting due to weakness, and inflammation. Sensory problems include tenderness, throbbing, pain, joint grinding (crepidation), swelling, redness, warmth, and aching (especially in cold weather).

Treatment of OA of the Thumb

Various treatments are available, such as injections, medication and surgical procedures. Specific Occupational Therapy treatments include splinting, physical exercises/activities and education about joint protection and energy conservation.

Types of Splints:

Custom Splints are very firm and are designed to fit your hand. They are designed to be worn as a "resting" splint. They provide a high level of support as they are designed for the wearer's hand only. They are easily cleaned and are long-lasting. Because of their firmness, they are hard to wear during activities, and are less comfortable to wear.

Prefabricated Splints are already made, softer splints used to place your thumb in a comfortable position. These splints are to help reduce pain and inflammation, and to help protect the arthritic joint. These splints may be worn during the day for most heavy demanding activities, are easy to clean and are comfortable to wear. Because they are not so firm, they do not provide a high level of support and tend to wear out due to day to day use.