Basal Thumb Arthritis Treatment

What is Basal Thumb Arthritis?

Basal thumb arthritis is an extremely common problem. When people develop basal thumb arthritis, they notice pain at the base of their thumb, as shown in this diagram in the red area. They have problems with pinching, which leads to pain and trouble opening jars as well as turning keys and opening doors.

What Causes Arthritis?

The cause of arthritis is damage to the cartilage surface between the bones. This can occur with daily use or wear and tear. It can occur as a result of a trauma, or it can occur as a result of chronic inflammation. This diagram shows the two bones that lose their cartilage and lead to basal thumb arthritis. These are the metacarpal bone and the trapezium bone.

Arthritis is very similar to the wear and tear that occurs on a car tire. If you imagine the tread on the car tire is very similar to cartilage and the rim is very similar to bone.
The damage to the cartilage, or the tread on the tire, usually occurs gradually over time and often is not noticed,
Until suddenly, there is a sudden onset of pain or a pop of the car tire, in the case of the car. So, the onset of pain or the pop in the tire is sudden but the wear in the cartilage, or the tread, is gradual.

How is it Diagnosed?

Patients with basal thumb arthritis, also known as CMC arthritis, may have a deformity at the CMC joint and they will have tenderness at this point, as shown here.
They may also develop a deformity at the MCP joint, which is the next joint in the thumb. When patients come to the office for an assessment of their basal thumb arthritis, pinch strength testing is done. We also check for deformities at other joints, such as the CMC joint and the MCP joint.
Diagnosis of the condition can also be confirmed with X-rays.

What is the First-Line Treatment?

Early on, non-surgical treatment is trialed. A splint, known as a thumb spica splint is used to stabilize the thumb. Decreasing motion of the thumb during activities can help to reduce the pain of basal thumb arthritis. Patients may also use anti-inflammatories. These can be topical, such as Voltaren gel that can be purchased without a prescription or oral, such as medications known as anti-inflammatories like ibuprofen or Advil.

What is the Next Option for Treatment?

If these treatments fail and pain persists, a steroid injection into the CMC joint can provide temporary relief. Relief can sometimes be obtained for three to 12 months with a single injection. The injections can also be repeated.

When is Surgery Indicated?

Surgery is indicated in three circumstances:

First, patients may have failure of nonsurgical treatment and ongoing pain. These patients may be good candidates for surgery.
Patients with extremely weak pinch of less than five pounds may be good candidates for surgery. Delaying surgery further can lead to chronic weakness of pinch. This photograph demonstrates a patient being tested with a pinch meter.
Finally, deformities of the MCP joint, the next joint over, is an indication for surgery. When this MCP joint here starts to hyperextend, surgery is indicated to avoid permanent changes of the MCP joint that lead to pain and disability that cannot be fixed.

What is the Surgery?

Surgery involves removal of the arthritic bone known as the trapezium, highlighted in this diagram. Once the trapezium is removed, the metacarpal bone, the next bone remaining shown here, is stabilized using a tendon from the forearm, known as the FCR tendon shown here.

The FCR tendon is used to stabilize the metacarpal and also to fill the space previously filled by the trapezium.

What Can I Expect After Surgery?

Surgery for basal thumb arthritis is a day surgery.
Patients will have increased pain in the area after surgery and increased pain or pain in the area can last for up to one month.
Patients need to stay in a thumb splint or a thumb spica device for four to six weeks.
After this, patients will undergo hand therapy to regain their motion.

What is the Expected Recovery?

Patients can expect to have minimal pain at the thumb by three months.
Patients can expect to have recovery of their preoperative strength by approximately six months.
By one year, most patients will develop strength that is greater than what they had prior to surgery.
Each year thereafter, their comfort and their strength will continue to improve. This is one of the only surgeries done where the results keep getting better over time.

Risks

There are risks with any surgery including basal thumb surgery. Risks include:

The anesthesia or anesthetic.
Injury to nerves, tendons.
Infection.
Ongoing pain.
Stiffness.
Scarring.

Summary

In summary, surgery for basal thumb arthritis is a reliable procedure.
It is indicated for patients with persistent pain, significant weakness or development of deformity at the next joint known as the MCP joint.
The recovery from surgery is long, however.
The results from surgery continue to improve over time.