Arthritis of the Basal Joint
Arthritis affects joints by the wearing, degeneration and thinning of the cartilage that joins bones together. Arthritis of the hand, particularly the thumb may be debilitating especially in people who have to use them at work.
The joint at the base of the thumb near the wrist is a common site of arthritis. It is usually found in women in their 40s, and is caused by constant rubbing of bony surfaces on the cartilage resulting in its degeneration and loss of elasticity. Inflammation can also be brought about by a previous injury to the joint.
Since the basal joint is involved in movements like pivoting, swiveling and pinching, using the thumb especially while gripping objects can result in severe pain in those with arthritis. Even simple movements like opening doorknobs, turning a key, or snapping fingers can be very painful. Other symptoms of arthritis include pain and inflammation of the joint, limitation of motion and bony deformity.
Arthritis of the thumb joint may be diagnosed by history, physical examination and X-ray images showing bony spurs and degeneration of the cartilage at the basal joint.
Treatment usually consists of resting and initially immobilizing the joint until swelling subsides. Pain medications may be taken and cold and heat therapy applied to the affected area. Physical therapy with gentle exercises is done when swelling and pain are reduced to mobilize the joint and strengthen the muscles around it.
Basal Joint Arthroplasty
When medical and physical therapy are inadequate to treat a severely damaged joint, arthroplasty may be an option. Basically, arthroplasty is known as joint reconstruction or joint replacement surgery, where the diseased joint is typically removed and replaced with a ceramic, plastic, silicone or metal prosthesis.
The drawback of this procedure however is the high incidence of wear of the implants, recurrent pain and instability of the joint and loss of strength. Consequently using prosthetic implants for the basal joint is recommended for older patients who have a relatively low level of functional activity.
For younger patients and more active patients, interpositional arthroplasty using tendon is advisable for the basal joint. This involves the reconstruction of soft tissues like ligaments around the thumb joint and the use of tendon repair to modify the joint space. Arthrodesis or joint fusion may be done in some cases.
After the operation the wrist and the arm are immobilized with a cast until healing occurs. After a few weeks hand and wrist exercises are done to mobilize the joint and strengthen the muscles.
Complications of basal joint arthroplasty include bleeding, infection and nerve damage resulting in weakness of the thumb.
In many cases pain is relieved and mobility is restored by basal joint arthroplasty. However, revisions may be done due to failure of the surgery in some cases. Consequently many other techniques have been developed for reconstructing the basal joint.
American Academy of Orthopaedic Surgeons, "Arthritis of the Thumb" accessed 1/20/11
Journal of Bone and Joint Surgery, “Arthroplasty of the basal joint of the thumb. Long-term follow-up after ligament reconstruction with tendon interposition" accessed 1/20/11