The earliest sign and symptom of thumb arthritis is pain, swelling, and tenderness with activities that involve pinching action. The pain may be dull, achy, or sharp at the base of the thumb. The pain can occur when we grip, grasp, or pinch an object or use the thumb to apply force. Other common early signs may include:
- Stiffness with loss of thumb movement: As the cartilage between joints wears away, most notice loss of mobility. Without the padding provided by cartilage, bone grinds against bone, resulting in joint stiffness. Stiffness may be more pronounced during the morning.
- Popping and grinding sound when the joints are flexed.
- Weakness: Pain, stiffness, and swelling can quickly lead to a decrease in strength. Tasks requiring a firm grip, such as opening jars, turning doorknobs/keys, or snapping the fingers, can become increasingly difficult.
- Pain worsens after prolonged use
- An enlarged “out-of-joint” appearance is usually noted
- Development of a bony prominence or bump over the joint
- Decreased range of motion of the thumb
- The thumb joint may bend backward (hyperextend) because it has to compensate for limited motion or pain
What are the possible causes of thumb arthritis?
A normal thumb joint is made of two smooth cartilages covered bone surfaces that fit well together and glide when the bone moves. However, if the smooth surface wears out, patients develop thumb arthritis with pain and swelling. The possible causes may include:
- Age: The older we get, the more likely we are to develop thumb arthritis. Over time, our cartilages that cushion and lubricate our joints wear down, eventually leading to arthritis.
- Genetics: Some people are genetically predisposed to developing thumb arthritis. The estimated onset time of thumb arthritis can usually be determined by family medical history.
- Gender: Unfortunately for women, females over the age of 40 years account for the largest percentage of thumb arthritis. They are 20 times more likely to develop arthritis in the thumb than males.
- Other contributing factors:
If the pain starts to interfere with daily activities of daily living, then a visit with a hand surgeon could be helpful. During a physical examination of an arthritic thumb, the physician may notice grinding when maneuvering the thumb in a certain way. X-rays are usually used to confirm the diagnosis.