thumb arthritis

Thumb arthritis, sometimes called basal joint arthritis, is a common cause of pain at the base of the thumb.  All joints are lined by smooth cartilage, and when this cartilage wears thin, normal motion of the joint can become painful.  Cartilage can wear out more quickly due to genetics, over-use, or prior injuries.

Symptoms

Patients with basal joint arthritis experience pain at the base of the thumb that tends to be worse during activities, such as when pinching objects, opening jars, turning doorknobs, or writing. 

Diagnosis

Thumb arthritis can be diagnosed by talking with your doctor and having them examine your hand.  X-rays can be useful to see the severity of the cartilage loss, and oftentimes will show development of bone spurs (osteophytes) - see figure above. 

Splinting of the base of the thumb.

Non-surgical treatment

  • Splinting of the base of the thumb during activities 
  • Ice, or heat (such as paraffin baths)
  • Anti-inflammatories (such as ibuprofen or naproxen – if medically safe)
  • Steroid injection into the arthritic joint
  • Therapy to strengthen the muscles around the thumb (see 3 videos below, courtesy of Stanford University Hand Therapy Rehabilitation)
Strengthening of the 1st dorsal interosseous muscle
Strengthening of the opponens pollicis muscle
Strengthening of the extensor pollicis brevis muscle

Surgical treatment

  • Many surgical treatment options are available for thumb arthritis.  My preference is to remove the trapezium and its bone spurs, and support the thumb on a bed of local tendon (like a hammock) to cushion the bone. 
  • A splint is worn for 4 weeks to allow healing, then motion and use of the thumb is resumed (see image on right) 
  • Therapy is often used after surgery to achieve optimal motion and strength

Surgical treatment of thumb arthritis involves removing the trapezium bone, and suturing together the APL and FCR tendons, thereby creating a soft "hammock" to support the thumb

If the arthritis involves the “STT” (scapho-trapezio-trapezoidal) joint, in addition to removing the trapezium bone, a small portion of the trapezoid bone is removed to create a space.  The defect fills in with scar tissue, which eliminates the “arthritic” STT joint.  The thumb is suspended with sutures.  The goal is to restore thumb motion and decrease pain.