Arthritis is a condition in which a joint wears out, or degenerates, usually slowly over a period of many years. The finger joints are covered on the ends with articular cartilage. This white, shiny material has a rubbery consistency. The function of articular cartilage is to absorb shock and provide an extremely smooth surface to facilitate motion. When this articular cartilage wears out there is bone on bone contact causing joint inflammation (pain, redness, heat, and swelling). The term degenerative arthritis means inflammation of a joint due to wear and tear. Degenerative arthritis is usually called osteoarthritis.
Injury to a joint, such as a bad sprain or fracture, can cause damage to the articular cartilage. An injury to any of the joints of the fingers, even if it does not injure the articular cartilage directly, can alter how the joint works.
After a fracture, the bone fragments may heal in slightly different positions. This may make the joints line up differently. When an injury changes the way the joint lines up and moves, force can start to press against the surface of the articular cartilage. This is similar to how a machine that is out of balance wears out faster. Over time, this imbalance in the joint can lead to damage to the articular surface. Since articular cartilage cannot heal itself very well, the damage adds up. Eventually, the joint can no longer compensate for the increasing damage, and symptoms begin.
Pain is the main problem with arthritis. At first, the pain usually only causes problems when you begin an activity. Once the activity gets under way, the pain eases. But after resting for several minutes the pain and stiffness increase. When the arthritis condition worsens, pain may be felt even at rest. The sensitive joint may feel enlarged and warm to the touch from inflammation.
In rheumatoid arthritis, the fingers often become deformed as the disease progresses. The MCP joints of the fingers may actually begin to point sideways (towards the little finger). This is called ulnar drift. Ulnar drift can cause weakness and pain, making it difficult to use your hand for daily activities.
Both rheumatoid arthritis and osteoarthritis can affect the IP joints of the fingers. The IP joints may begin to flex (bend) or hyperextend (over straighten), causing characteristic finger deformities.
Swan neck deformity occurs when the middle finger joint (the PIP joint) becomes loose and hyperextended, while the DIP joint becomes flexed. When the PIP joint flexes and the DIP joint extends, a boutonniere deformity forms. Both forms of arthritis can cause enlarged areas over the back of the PIP joints. These areas tend to be sore and swollen. They are known as Bouchard's nodes. Osteoarthritis causes similar enlargements over the DIP joints, called Heberden's nodes.
Treatment usually begins when the joint first becomes painful. This may only occur with heavy use and may simply require mild anti-inflammatory medications, such as aspirin, ibuprofen or topical gel/cream. Reducing the activity, or changing from occupations that require heavy repetitive hand and finger motions, may be necessary to help control the symptoms.
A steroid injection of cortisone into the finger joint can give temporary relief. Cortisone is a very powerful anti-inflammatory medication. When injected into the joint itself, it can help relieve the pain. Pain relief is temporary and usually only lasts several weeks to months. There is a small risk of infection with any injection into the joint, and cortisone injections are no exception.
Rehabilitation services, such as physiotherapy, play a critical role in non-operative treatment of finger joint arthritis. The main aim is to help you learn how to control symptoms and maximise the health of your hand and fingers. You will learn ways to calm pain and symptoms, which might include the use of rest, heat, or topical rubs. A custom finger brace or splint may be prescribed to support the finger joints. These devices are designed to help reduce pain, prevent deformity, or keep a finger deformity from getting worse.
A fusion (or arthrodesis) of any joint is designed to eliminate pain by allowing the bones that make up the joint to grow together, or fuse, into one solid bone. Fusions are used in many joints and were very common before the invention of artificial joints for the replacement of arthritic joints. Even today, joint fusions are still very commonly used in many different joints for treating the pain and potential deformity of arthritis. Fusions are more commonly used in the PIP or the DIP joints in the fingers. A fusion of these joints is far easier and more reliable than trying to save the motion by replacing the joint.
Joint replacement - artificial joints are available for the finger joints. These plastic or metal prostheses are used by some hand surgeons to replace the arthritic joint. The prosthesis forms a new hinge, giving the joint freedom of motion and pain relief. The procedure for putting in a new joint is called arthroplasty.