Normal Joint Osteoarthritis
Consequences of DIP joint Osteoarthritis
1. Pain – The pain is variable. Often the joint may be “irritable” for days or weeks. The joint at this time is having a “flare”. It may be slightly red and warm. Often the pain settles but the joint is left swollen with bony spurs and may become a little stiff.
2. Deformity – If the degeneration of the cartilage is uneven and wears out more on one side of the joint than the other then the joint may angulate.
3. Heberden’s nodes – Are the bony spurs on the back of the finger. They may be quite prominent but are often painless.
4. Mucous cysts – occasionally cysts arise from the arthritic joint and can cause nail deformity
- More information
TREATMENT
1. Observation – many people with arthritis in the D.I.P.joint have no pain at all.
2. Anti – inflammatory tablets or Paracetamol
3. Surgery - Fusion of the Joint
- The major Indication for surgery is Pain. Spurs on the joint may be unsightly to some people but this is not a good reason to have surgery.
- Involves stiffening ( Fusion) of the D.I.P. joint. ie the arthritis is removed and the bones are joined together ie the end joint of the finger can no longer move. Deformity can be corrected by cutting the bones parallel to the long axis of the bone. When one joint is fused it places more stress on the adjacent joints. Under these circumstances it is vital that the PIP joint range of motion is well preserved. At the time of fusion spurs are removed from the joint to improve the appearance of the finger. The finger is inevitably slightly shortened.
After resection of the remaining cartilage from the joint with bone resection back to bleeding bone the joint is stabilised using a screw inserted through a small incision in the finger pulp under Xray control. The screw does not need to be removed.
- The surgery is performed in hospital as a day only procedure. At the end of the procedure local anaesthetic is inserted so that there is no pain for 6 – 12 hours.
- After the operation the finger is immobilised in a splint for 6 weeks or until the fusion is solid
Complications:
1. Numbness at the base of the nail - the incision to gain access to the joint must cut through tiny branches of the skin nerves on the back of the finger. This results in variable numbness at the base of the nail. This area of sensation is not critical but in can result in scar tenderness or hypersensitivity
2. Tender scar
3. Nail deformity – it is common that a transverse ridge forms in the nail after a DIP fusion . It is known as a Beau’s line and gradually grows out at a
rate of 0.1mm per day. Ie 3 – 6 months. Permanent nail deformity is possible but uncommon.
4. Non - union of the fusion ( rare) It is more common in smokers so it is highly desirable to stop smoking if you are undergoing this procedure.
Example 1
Multiple DIP joint fusions can be performed at the same time – but only one hand at a time. It is vital to exercise the PIP joints immediately to prevent stiffness. In this case the deformity has been corrected.
Example 2:
DIP Fusion combined with PIP joint replacement.
If there is symptomatic arthritis in both the PIP & DIP joints then the PIP is replaced and the DIP fused. The results of DIP fusion are more reliable than PIP joint replacement. The problem is that the PIP joint replacement will eventually wear out or loosen. In this case both joints need to be addressed because of the “Z” deformity. Ie the deformities at each joint balanced each other . If the DIP joint had been fused only the finger would have deviated sideways towards the little finger. When one joint is fused it places more stress on the adjacent joints.
Revised 10 / 6 /21