Osteoarthritis fingers thumbThere are several bones that make up the hand. The main knuckle joint is formed by the relationship of the phalanges to the metacarpals. This joint is called the metacarpophalangeal joint, abbreviated MCP. This joint acts like a hinge when you bend and straighten your fingers and thumb. The three phalanges in each finger are separated by two joints, called interphalangeal (IP) joints. The one closest to the MCP (knuckle) is called the PIP, or proximal IP joint. The joint near the end of the finger is called the DIP, or distal IP joint. The thumb only has one IP joint between the two thumb bones. The IP joints of the digits also work like hinge joints when you bend and straighten your hand. The finger and thumb joints are covered on the ends with articular cartilage. This white, shiny material has a rubbery smooth consistency. The function of articular cartilage is to absorb shock and provide a smooth surface to facilitate motion. There is articular cartilage essentially everywhere that two bony surfaces move against one another, or articulate. Degenerative arthritis is a condition in which a joint wears out, or degenerates, usually slowly over a period of many years. The term arthritis means joint inflammation (pain, redness, heat, and swelling). The term degenerative arthritis means inflammation of a joint due to wear and tear. 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. This is true for a fracture that involves the joint when the bone fragments don't quite "line up" correctly and heal differently from the way they were before the break occurred. 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. The damage in the joint starts well before the symptoms of arthritis appear. Pain is the main problem with arthritis. At first, the pain usually only causes problems when you begin an activity. Once the activity gets underway, 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. Arthritis can affect the IP joints of the fingers. Osteoarthritis may cause soreness and swelling on the back of the PIP joints. These enlargements are known as Bouchard's nodes. Patients with osteoarthritis of the fingers may have swelling and tenderness over the top of the DIP joints. These enlargements are called Heberden's nodes. Osteoarthritis at the base of the thumb is also very painful. This affects the ability of the thumb to perform pincer movement; therefore, grip strength is affected. The ability to grasp is greatly affected. The diagnosis of arthritis of the finger joints begins with a history of the problem. Details about any injuries that may have occurred to the hand are important and may suggest other reasons why the condition exists. Following the history, a physical examination of the hand, and possibly other joints in the body, will be done. Your doctor will need to see how the motion of each joint has been affected. X-rays may be taken to see how much the joint has changed. These tests can help determine how bad the degenerative damage from the arthritis has become. The X-rays also help the doctor estimate how much articular cartilage is still on the surface of the joints. 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 other medications. Reducing the activity, or changing from occupations that require heavy repetitive hand and finger motions, may be necessary to help control the symptoms. Topical agents may also help. An injection of cortisone into the finger joint can give temporary relief. Cortisone is a very powerful anti-inflammatory medication and when injected into the joint itself 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 physical and occupational therapy, play a critical role in nonoperative treatment of finger joint arthritis. A primary goal is to help you learn how to control symptoms and maximize the health of your hand and fingers. You'll learn ways to calm pain and symptoms, which might include the use of rest, heat, or topical rubs. A special brace may be prescribed to help support the hand and fingers to help reduce your pain and prevent deformity. Range of motion and stretching exercises are prescribed to improve your finger movement. Strengthening exercises for the arm and hand help steady the hand and protect the finger joints from shock and stress. Your therapist will go over tips on how you can get your tasks done with less strain on the joint. A fusion (also called an 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. 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.
|
