Surgery for Thumb Arthritis
Experts explain five surgical treatment options for thumb arthritis.
Most activities that involve grasping or pinching are possible because of the thumb's remarkable range of motion. But dexterity comes at a price – an increased risk of osteoarthritis in the first carpometacarpal (CMC) joint, where the thumb meets the trapezium bone in the wrist. Sometimes the joint becomes so damaged that surgery is necessary.
Problems often start when the thick ligaments that hold the joint together loosen, allowing it to slip out of place. Over time, the articular cartilage that cushions the ends of the bones wears away, causing pain and limiting movement. Rheumatoid arthritis (RA) and other forms of inflammatory arthritis can also damage the first CMC joint – also known as the trapeziometacarpal joint (TMC).
David S. Ruch, MD, chief of the orthopaedic hand service at Duke University in Durham, N.C., says women, especially those older than 50 are 10 to 20 times more likely than men to develop thumb arthritis, though no one is quite sure why.
Both women and men respond well, at least initially, to conservative measures such as anti-inflammatories, splints, activity modification and limited steroid injections. For some, says Dr. Ruch, these may be the only treatments needed.
“[These therapies] make people feel better, but they don’t stop disease progression, and eventually surgery may be necessary,” he says.
Several surgical options are available, and the best approach depends on the stage of the disease and severity of symptoms. Broadly speaking, most thumb surgeries remove some or all of the arthritic bone and use various methods to stabilize the joint.
This procedure stabilizes the CMC joint by removing a portion of the damaged ligament and replacing it with a piece of the patient’s wrist flexor tendon.
“The transposed tendon reconnects and restores mechanical function of the thumb with the rest of the hand,” says Stephen Trigg, MD, an orthopaedic hand surgeon at Mayo Clinic in Jacksonville, Fla.
Who can benefit: Adults with no cartilage loss whose symptoms result from joint laxity.
Pros: Most people with very early or pre-arthritis experience good to excellent pain relief. Studies suggest ligament reconstruction also prevents disease progression in a majority of patients.
Cons: The procedure stabilizes the joint but does not repair damaged cartilage or bone.
Ligament Reconstruction and Tendon Interposition (LRTI)
In use for more than 40 years, LRTI is the most commonly performed surgery for thumb arthritis. The arthritic joint surfaces are removed and replaced with a cushion of tissue that keeps the bones separated. To accomplish this, surgeons remove all or part of the trapezium bone in the wrist.
A nearby tendon is detached at one end and then passed through a hole drilled in the thumb metacarpal. The remaining tendon is rolled like an anchovy and placed into the space where the bone was removed. Surgeons can also use artificial “anchovies” that eliminate the need to move a tendon.
Who can benefit: Adults with moderate to severe arthritis with pain and difficulty pinching or gripping.
Pros: Removing the entire trapezium eliminates the possibility of arthritis returning, and, according to Dr. Ruch, LRTI has a 96 percent success rate. “Most patients achieve complete pain relief and mobility equal to that of a healthy thumb, with results lasting at least 15 to 20 years,” he says.
Cons: LRTI has a lengthy and sometimes painful recovery and rehabilitation period, including at least four weeks of wearing a thumb cast. Patients also may experience decreased pinch strength, making it difficult to grasp and hold objects. LRTI also noticeably shortens the thumb. When the entire trapezium is removed, there are few repair options if symptoms persist after surgery.
Hematoma and Distraction Arthroplasty
In this simple, somewhat controversial procedure, surgeons remove the trapezium bone in the wrist and, with a wire, temporarily immobilize the thumb. The wire is removed six weeks later. The idea is that, without the constant friction caused in part by the trapezium, the body can heal itself.
Who can benefit: People with moderate to severe arthritis who want a less complicated surgical procedure; older, less active patients; and those who have had a failed reconstruction procedure.
Pros: Most patients get complete pain relief, an increase in grip strength and improved overall function. This procedure avoids complications associated with tendon harvesting and more complex operations.
Cons: Removal of the trapezium has been known to come with significant complications, including loss of pinch strength and thumb shortening. Proponents of the procedure claim immobilizing the joint for a few weeks prevents these complications.
Total Joint Replacement (Arthroplasty)
Like hip or knee replacement, this procedure removes all or part of the damaged thumb joint and replaces it with an artificial implant. Early implants were made of silicone. Surgeons now use metal or pyrocarbon prostheses and cushioning synthetic spacers that sit between the bones.
Who can benefit: Metal joint replacements are an option for older patients with few functional demands because the implants tend to fail with heavy use. Spacers, which have lower failure rates but higher complication rates, are generally reserved for younger or very active adults with more advanced disease.
Pros: Thumb arthroplasty is a less invasive surgery (because there is no grafting) with a faster recovery and rehabilitation. Some implants are placed without removing the trapezium, thereby preserving healthy tissue, improving strength and providing options if additional procedures are needed.
Cons: Spacers have high complication rates for some patients, including bone damage (osteolysis), persistent pain and inflammation. As for other prostheses, the jury is still out. So far, they have not proved as reliable or durable as tendon grafts, Dr. Ruch says.
Arthrodesis eliminates pain by fusing the bones in the joint together. Surgeons create a socket by hollowing out the thumb’s metacarpal bone and then shaping the trapezium into a cone that fits inside the socket. A metal pin holds bones together to maintain proper alignment and prevent movement while the bones fuse.
Who can benefit: Younger, active patients who have posttraumatic arthritis or physically demanding jobs (and may therefore wear out an implant quickly); people with RA; and those who have undergone thumb surgery but haven’t gotten relief from symptoms.
Pros: Arthrodesis produces a stable, pain-free thumb that can grasp and pinch.
Cons: The procedure has a relatively high complication rate, can damage nearby joints and causes loss of mobility in the CMC joint, including the ability to lay the palm flat and put the fingers and thumb together in a cone shape. Complications are more likely in people older than 40, according to a 2014 Journal of Bone and Joint Surgery study. Arthrodesis fails in 8 to 21 percent of people, requiring a repeat surgery.