Arthrodesis is the process of surgically fusing a joint, usually irreversibly. It is achieved by removing the articular surfaces of both joints and then holding the bone ends together, as in a fracture. Either internal or external fixation may be used. Larger joints may require some bone grafting to promote union.
Arthrodesis is indicated for a painful, damaged or unstable joint, where the loss of movement does not in itself produce unacceptable immobility. It is often used in the spine, the tarsus, the wrist and the interphalangeal joints. It is less commonly advised for joints such as shoulder or the knee.
Arthrodesis of the hip is more contentious: there is loss of movement at the hip, but the younger patient is often able to compensate through hypermobility of the lumbar spine and knee.
Arthrodesis is not advised when there is a risk that other joints will become stiff - for example, the hip with an already arthrodesed knee on the same limb; or if the second hip is highly likely to stiffen.
To aid decision in a difficult case, one can try immobilising the affected joint in plaster and see which is more preferable to the patient - an immobilised, painless joint or a mobile but painful one.
The main complication of the procedure is non-union with a pseudarthrosis.
Last reviewed 01/2018