Pain, swelling, and loss of motion at the base of the thumb describe symptoms of carpometacarpal osteoarthritis (CMC OA) otherwise known as thumb arthritis. Just try and get along on a single day without being able to use your thumb. Everything from picking up a carton of milk to taking the handbrake off in the car can become impossible.
Over time, the thumb becomes weaker and weaker. With loss of normal strength, the thumb loses its anatomic alignment. Deformity and disability develop. Pretty soon even simple tasks such as picking up a piece of paper or turning a doorknob become impossible. That’s when surgery becomes a viable option.
Because so many older adults develop arthritis at the base of the thumb with severe symptoms, surgeons have developed a variety of ways to surgically treat the problem. At last count, there were at least eight different procedures that could be used to treat thumb osteoarthritis.
In this review, hand surgeons tally up the results of studies in this area published from 1966 to 2009. The surgical procedures included 1) removing the trapezium bone (trapeziectomy) and filling in the hole with a spacer or rolled up piece of ligament (interposition), 2) same procedure using a piece of tendon instead of ligament, 3) removal of the trapezium and ligament reconstruction, 4) just ligament reconstruction, or 5) trapeziectomy with both ligament reconstruction and tendon interposition.
There were other surgical procedures as well such as an arthrodesis (joint fusion), joint replacement, or osteotomy. An osteotomy is the removal of a wedge-shaped piece of bone to help realign the entire bone and joint. Once the piece of bone is taken out, the remaining two edges of bone shift toward each other and change the structural alignment.
Studies are evaluated by design and quality. Strength of evidence is gauged from poor to good. Studies with the lowest level of evidence are usually case reports or series of cases with no control group. Studies with the highest level of evidence are randomized controlled trials with large numbers of people in the experimental and the control groups. A meta-analysis like this one that only includes randomized controlled trials yields the best level of evidence to guide treatment.
The authors provide a detailed table of information obtained from the studies reviewed. Authors, level of evidence, number of patients in each group, type of procedure, and results are recorded. It’s easy to see from this layout that patients and results weren’t always assessed in the same way from study to study. Sometimes patient satisfaction was the main measure. Most of the time, joint motion, strength, and function were the key areas assessing outcomes.
Other measures included revision rates (need for further surgery), number and type of complications after surgery, speed of recovery, ability to perform specific job tasks (including light to heavy work), and results of biopsy exams (looking for signs of foreign body reaction and incorporation of implants into the bone).
After reviewing results of studies for each surgical procedure, the following conclusions were made:
At this point, there was no single surgical procedure that stood out as the best one to use for the problem of carpometacarpal (CMC) osteoarthritis (OA). In general, most of the studies only give results after a short period of time (one year). A true comparison needs long-term results since patients are looking for a lasting improvement. The authors suggest a need for more studies to really find out what works best in the long-run. A specific suggestion was made to find better ways to measure results, especially related to hand function.