Osteoarthritis of the thumb
What is it?
Osteoarthritis affecting the carpometacarpal (CMC) joint of the thumb.
Osteoarthritis affecting the carpometacarpal (CMC) joint of the thumb.
History
The majority of patients have no or minimal symptoms, but the condition can cause stiffness, grinding, and a dull ache which becomes sharp with the use of the thumb. This particularly occurs during pinching or gripping movements that can cause the sufferer to drop objects. It is very common in women over 50 years of age and tends to run in the female side of families.
The majority of patients have no or minimal symptoms, but the condition can cause stiffness, grinding, and a dull ache which becomes sharp with the use of the thumb. This particularly occurs during pinching or gripping movements that can cause the sufferer to drop objects. It is very common in women over 50 years of age and tends to run in the female side of families.
Examination
The base of the thumb may appear to be prominent. The thumb may lie more in the palm (adducted) which is secondary to subluxation of the CMC joint. There is often tenderness over the base of the thumb. Range of movement is reduced and painful.
Special tests
The Grind Test (axial compression and circumduction) is painful.
Differential Diagonosis
- STT arthritis
- DeQuervain’s Tenosynovitis
- Ganglion
- Scaphoid non-union +/- subsequent arthritis
Radiographs
True AP view of thumb base (Roberts view) and Lateral radiographs will confirm the diagnosis.
Treatment options
Here are the treatment options available for Osteoarthritis of the thumb:
- Initially rest and modification of activities or change of work practices.
- Analgesia or anti-inflammatory medication.
- Splint.
- Intra-articular injection of steroid may also be given depending on the severity of the arthritic changes.
Surgery
1st CMCJ Arthroscopy:
The thumb base joint can be visualised directly with the use of small arthroscopes (keyhole technique). This is used rarely for very early thumb base pain in younger patients.
Trapeziectomy:
The trapezium (the small bone at the base of the thumb) is removed. It is sometimes necessary to stabilise the thumb by using a wrist/thumb tendon. Occasionally a pin is placed to temporarily “stabilise” the thumb base. This is the most common procedure performed in the UK for this type of arthritis.
Joint replacement:
Mr Crook offers pioneering joint replacement surgery in the form of the Cartiva implant for base of thumb arthritis. Mr Crook is one of the Principal Investigators for the GRIP 2 study. He is one of only four UK surgeons involved in this prestigious International research trial in conjunction with highly regarded centres in the United States.
Traditionally the arthritic joint is replaced with either a Pyrocarbon or a Silicone joint. The long-term outcome of this operation is very variable. There are specific problems associated with these type of joint replacements such as loosening and dislocation. The Cartiva implant offers a possible solution to some of these problems.
Metacarpal osteotomy:
The metacarpal bone (at the base of the thumb) is divided and repositioned to offload the worn part of the joint. This can reduce pain and improve use of the thumb for patients with mild/early arthritis.
Joint fusion:
The arthritic joint is removed and then two bones are fused together making one bone. This is most often performed in young and middle aged men who do manual work, and is thought to preserve the strength of the thumb better than other procedures.
When to refer:
Many patients with early osteoarthritis of the thumb can be managed in the community using a combination of analgesia, splinting and activity modification. The selective use of intra-articular injections can provide excellent benefit in patients with early to moderate degenerative changes.
Failure to control symptoms despite the above measures or in severe disease warrants onward referral to the Hand Clinic.