Base of the Thumb Arthritis
Osteoarthritis, also known as degenerative arthritis, is a mechanical abnormality, involving degradation of the joint cartilage and bone. Symptoms include joint pain, stiffness, locking and sometimes, swelling as a result of a joint effusion. All joints are predisposed to developing arthritis.
Arthritis of the thumb basal joint, in particular affecting the first carpometacarpal joint is a frequent site due to its relative instability and high utilisation. This occurs when the cushioning cartilage of the joint surfaces wears away, resulting in damage to the thumb joint. Pain at the base of the thumb occurs when moving the thumb and sometimes persists even at rest.
Risk Factors of Thumb Arthritis
A variety of causes – hereditary, developmental, metabolic and mechanical deficits may initiate and exacerbate the loss of cartilage. Ligament injuries and laxity may also exacerbate the lesion.
Diagnosis and Differentials of Thumb Arthritis
Diagnosis is based a combination of clinical findings as radiologic imaging (Figure A).
Differentials include fracture, carpal tunnel syndrome and other inflammatory joint arthritis.Discuss the different options with the hand specialist looking after you, so that the most appropriate modality is chosen
Management of Thumb Arthritis
Treatment for thumb arthritis involves multiple modalities, including activity modification, rest, immobilization, analgesia and even surgery
A resting thumb spica splint is usually prescribed in the initial stage (Figure B). This can be further supplemented with corticosteroid or hyaluronic acid injections.
If conservative management does not reduce or control the symptoms, then surgical treatment is indicated.
Various surgical options are available, depending on the severity of the lesion:
- Thumb arthroscopy – this involves making 2 small puncture holes to enable the doctor insert a videocamera inside the affected joint. This allows debridement and synovectomy of the joint, as well as direct visualization of the condition of the articular cartilage. This technique is effective in the early stages of arthritis.
- Trapeziectomy with tendon interposition and/or ligament reconstruction
- Joint arthrodesis
- Joint replacement
Discuss the different options with the hand specialist looking after you, so that the most appropriate modality is chosen.