Aching, stiff fingers and wrists can be a sign of osteoarthritis in the hands. Large, arthritic knuckle joints can make it more difficult to get rings on and off. These changes may also cause some people to feel self-conscious about the appearance of their hands.1
Hand osteoarthritis can affect just one joint, such as the joint at the base of the thumb, or several joints in the fingers, wrist, and thumb.
How Osteoarthritis Affects Hand Function
Pinching and gripping objects may become more difficult, making tasks such as picking up a quarter, putting toothpaste on a toothbrush, and using a mobile phone challenging.
Exactly how osteoarthritis affects hand function depends on which joints are involved2:
- Arthritis in the thumb and middle, ring, and pinky fingers is associated with weaker grip strength.
- Arthritis in the thumb and index finger is associated with weaker pinch strength.
- Wrist arthritis is associated with carpal tunnel syndrome,3 which can weaken hand grip and cause numbness and tingling, particularly in the thumb, index, and middle fingers.
Not surprisingly, people who have osteoarthritis in the thumb, index finger, and/or middle finger—the digits required for gripping and pinching objects—tend to report more problems than people who have osteoarthritis in only the ring or pinky finger.2
Hand dominance and arthritis One study found 80% of hand arthritis cases involve people’s dominant hands.4 A separate study found that osteoarthritis was not as strongly associated with hand dominance.5 It may be that people are more likely to seek medical care when the dominant hand is affected.
Hand Joints Are Most Affected By Osteoarthritis
The hand has 27 joints.6 Each finger has 4 joints—3 knuckles and 1 joint that connects its long bone in the hand (called a metacarpal bone) to the wrist. The thumb has 3 joints and the wrist contains 8 joints.
While any joint in the hand can develop osteoarthritis, the joints most often affected include:
- The proximal interphalangeal (PIP) joints, or middle knuckles of the fingers
- The distal interphalangeal (DIP) joints, or the end-most joint of the fingers and thumb
- The basilar joint (sometimes called the first carpometacarpal joint) at the base of the thumb
- Certain joints of the wrist that connect the wrist’s 8 carpal bones with each other and the bones of the forearm (the radius and ulna)
The metacarpophalangeal (MCP) joints, the largest knuckles of the hand, are less likely to be affected by osteoarthritis.
How Hand Osteoarthritis Develops
Where bones meet to form a joint, their surfaces are covered with smooth, slippery cartilage. This cartilage provides a cushion between the small bones of the hand, protecting them from rubbing directly against each other. When this cartilage deteriorates, it is called osteoarthritis.
Exactly what causes cartilage to deteriorate is not clear to researchers,1 and may vary from person to person. The hands do not bear weight but its joints undergo stress on a daily basis, such as when carrying objects or gripping items. Aging and genetics also play roles.
As cartilage deteriorates, other changes in the hand also occur:
- Friction between bones can lead to the development of bone spurs (these spurs are typically what make arthritic knuckles look bigger).
- The bone underneath damaged or missing cartilage may develop cysts and areas of abnormal swelling called bone marrow lesions.
- The delicate membrane that encapsulates each small finger joint can become inflamed.
- The area where tendons insert into bone, called entheses, can also undergo inflammatory changes.
While bone spurs tend to be permanent, the other changes may get better or worse. They can lead to permanent damage or go away altogether.
Read more about Osteoarthritis Causes
How Hand Arthritis Causes Pain
Cartilage does not contain nerves, so damaged cartilage is not a source of pain. Likewise, bone spurs are normal signs of aging, and not necessarily a cause of pain. Rather, arthritic hand pain and stiffness occur when the changes described above lead to inflammation and swelling. In addition, bone cysts seem to be directly associated with osteoarthritic pain.
When Hand Arthritis Is Serious
Hand arthritis can be a serious cause for concern if it prevents a person from being able to care for themselves, particularly if they live alone. Hand arthritis can also be serious if it leads to severe carpal tunnel syndrome. Advanced carpal tunnel causes numbness and/or tingling and weakness in the thumb and associated fingers, and can result in permanent nerve damage if left untreated. In either of these cases, consultation with a medical professional is advised.
Read more: Is My Hand and Wrist Pain Caused by Carpal Tunnel Syndrome or Something Else? on Sports-health.com