Thumb arthritis, or basal joint arthritis, is the result of the wearing away of cartilage in the joint at the base of the thumb.
The basal joint allows your thumb to move around so you can perform small motor tasks. Without plenty of cushioning cartilage, the joints become rough and grind over each other when you move, causing more joint damage. It can also be caused by injury to the thumb.
Symptoms of thumb arthritis
Hand pain and stiffness
Usually, the first sign of arthritis in the thumb is pain, tenderness, and stiffness. You’re most likely to feel it at the base of your thumb as you try to grip, pinch, or clasp something between the thumb and index fingers. You might also feel a pain when you try to apply mild force, such as when you twist a key in a lock, turn a door handle, or snap your fingers. You might be left with a lingering ache. A high level of pain doesn’t always mean your arthritis is more severe.
Decreased strength and range of motion
Over time, pain and inflammation can rob your hand of strength and restrict your range of motion. These restrictions become especially obvious when you try to pinch something or clasp an object tightly. You might find it increasingly difficult to open jars, hold a drink, or use buttons, zippers, and snaps. For those with a severe case of arthritis in the thumb, small motor tasks that were once a matter of routine become too painful to attempt, or almost impossible to accomplish without assistance.
The thumb may appear swollen, especially at its base, and you may develop a bony bump. Overall, the base of the thumb can take on an enlarged appearance. One alarming sign of thumb arthritis is improper alignment of the joint as it shifts from its normal positioning. This may affect the joint above the base as well, creating a bent-back appearance (hyperextension). In particularly severe cases, the thumb cannot get out of the palm of the hand.
Arthritis is different in each individual. There are a variety of treatments that may work for your particular symptoms.
Initial treatment options involve:
- application of ice
- steroid injections
If these methods do not relieve pain and improve function, the joint may need to be reconstructed with surgery.
If exercise, medications, and splinting do not sufficiently reduce pain and restore range of motion and strength, surgery may be required.
Possible surgeries for thumb arthritis include:
- Trapeziectomy: one of your wrist bones involved in the thumb joint is removed.
- Osteotomy: the bones in your joint are moved and aligned correctly. They may be trimmed to remove excess growth.
- Joint fusion: the bones in the joint are fused. This improves stability and reduces pain. However, there is no longer flexibility in the joint, and you will no longer be able to perform certain tasks.
- Joint replacement: the joint is replaced with metal and plastic components.