Damaged joints become stiff, weak and painful. This interferes with activities of daily living and with sleep, and can convert a person who was an outgoing and independent contributor to society into a depressive reliant on society for their needs.

Joints most commonly fail because of idiopathic osteoarthritis – the collapse of the articular cartilage for no known cause. However, joints can also fail as a result of the destruction caused by destructive arthritis or even fractures into the joint. If the surface of a joint heals with more than a 2 mm step in the surface, the onset of early traumatic arthritis is thought to be almost inevitable. Arthritic pain at night is a deep ache within the bones of the joint, while during the day the joint is stiff and hurts when it is moved.

The options to manage the symptoms are painkillers, physiotherapy and aids to ease activities of everyday living, such as splints and home aids. Injections of local anaesthetic and even steroids into the joint give only minimal short-term benefit and run the risk of introducing infection into the joint.

Surgically the options are either to fuse the joint, excise it, or replace it.

• Fusion removes all movement but should create a strong limb which is pain-free.
  
• Excision should also remove pain but preserves movement although strength is lost because the muscles no longer have a fulcrum across which they can operate.
  
• Replacement should remove pain, improve mobility at least a little, and provide a strong limb.