Joint deformity can occur in various joints but are most common in the hands and feet. Causes of joint deformity include injury and degenerative conditions such as osteoarthritis.

A joint is where two bones meet and where movement can occur. Examples of joints include the knees, shoulders, hips, fingers, elbows, and toes.

A joint deformity occurs when a joint becomes bent out of shape. This can happen to any joint of the body.

Damage to a joint can occur for various reasons. However, it is usually a result of arthritis, fractures, or other injuries.

This article looks at common types of joint deformity, their causes, treatment, how to manage them, and prevention tips.

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Joint deformity is common in the hands because the hand contains various joints that a person uses regularly.

Common hand joint deformities include:

  • Boutonniere deformity: This occurs when the middle finger joint bends closer toward the palm. The outer finger may bend away from the palm.
  • Swan-neck deformity: This is when the joint at the base of the finger and the outermost joint bend while the middle finger joint straightens.
  • Hitchhiker’s thumb: The base of the thumb becomes bent, and the top section of the thumb extends. This is also known as a Z-shaped deformity.
  • Mallet finger: Mallet finger occurs when the end joint of a finger bends.
  • Ulnar drift: This is where the fingers bend toward the pinky.
  • Bouchard’s nodes: These are bony bumps that develop in the middle joint of the finger.
  • Heberden’s nodes: These are the same as Bouchard’s nodes, but they develop on the end joint of the fingers instead.

Foot deformities are also common. Some common foot deformities include:

  • Flat feet: Someone with flat feet has arches that disappear when standing.
  • Bunions: A bony bump on the inner side of the big toe.
  • Hammertoe: The joint on the second toe bends into a hammer shape.
  • Claw toe: The end and middle of the toe joint bend downward into a claw shape and the base bends upward.
  • Mallet toe: This occurs when the end joint in one of the toes bends downward.

Joint deformities may also occur in the hip, knees, shoulders, and elbows.

Learn more about joints and how they work here.

Joint deformity can occur for various reasons, including:

Osteoarthritis (OA)

OA is the most common form of arthritis.

Approximately 50% of all females and 25% of all males will experience OA pain in their hands by the time they are 85 years of age.

Pain, stiffness, and swelling are all common symptoms of OA.

A person with OA can also develop joint deformity. Joints can become enlarged and out of shape due to swelling, loose ligaments, loss of cartilage, and changes to bones.

Learn about OA flares here.

Rheumatoid arthritis (RA)

Rheumatoid arthritis (RA) is an autoimmune condition affecting several joints.

When RA affects a joint, the joint becomes inflamed and swollen. This may cause damage to the tissue, which can lead to deformity. A person may also develop chronic pain and instability.

Learn more about the symptoms of RA here.

Fractures and injury

The body will mend a fracture, or broken bone, naturally.

However, treatment is important to help the bone mend properly. If the two ends of the bone do not realign properly, a deformity in the joint can develop. Sometimes, surgery may be necessary.

Injuries or traumas that do not cause fractures can also result in deformities.

Learn more about fracture repair here.


This is a long-term condition affecting the joints, skin, and organs. It can also result in fatigue.

Approximately 10% of individuals with lupus develop joint deformities.

Lupus causes a form of arthritis that results in joint pain and inflammation. In some people, this can cause deformity, particularly in the fingers.

This deformity occurs due to ligament or tendon laxity. This is when tendons or ligaments are looser than usual.

Learn more about the symptoms of lupus here.

Bone or cartilage cancer

Bone or cartilage cancer can result in deformities.

This may occur due to tumors that weaken and destroy the bone or cartilage. This weakness or bone destruction can then lead to deformity and fractures.

Learn more about cancer in our dedicated hub here.


Osteomyelitis is a painful bone infection that can cause severe deformity. Joint deformity may occur due to bone death.

Learn more about bone pain here.

The treatment for joint deformity varies depending on the cause, type, and severity. A person may also receive treatment for the underlying cause.

One possible treatment option is occupational therapy. While occupational therapy cannot reverse the effects of joint deformity, an occupational therapist can teach a person exercises to help retain flexibility and movement in the joint.

They can also help people adapt by instructing them to avoid certain activities and use other stronger joints for some tasks.

Occupational therapists may also supply splints or braces. These can help to slow the progression of the damage and provide support.

Some people require joint replacement surgery, which can help a person regain movement in the joint.

Learn about joint replacement surgery for RA here.

Some people may benefit from frequent visits to an occupational therapist to learn about exercises and adaptations to help them manage their condition.

People may benefit from splints and braces to support the joint. They can also slow the progression and help manage pain.

Additionally, non-steroid anti-inflammatory drugs (NSAIDs) can help a person manage pain. Doctors may also recommend corticosteroid injections, which may reduce inflammation and pain.

Other strategies people can try to control joint pain include:

Learn how to manage chronic pain here.

According to the Arthritis Foundation, people with RA can avoid joint deformities if they take disease-modifying anti-rheumatic drugs (DMARDs). However, it is important to start treatment early, before any bone erosion occurs.

A person can also try to avoid joints problems by:

  • controlling blood sugar
  • exercising frequently
  • stretching daily
  • avoiding injuries and fractures
  • stopping smoking

If a person knows they are at risk for any joint disorders, a healthcare professional can advise them about preventive strategies.

Learn more about RA in our arthritis hub here.

Joint deformity can occur in any joint in the body. It commonly affects the hands and feet.

It can happen for various reasons. Joint deformity can be due to OA, RA, fractures and injury, lupus, bone or cartilage cancer, and osteomyelitis.

Treatments cannot reverse joint deformities. However, they can reduce pain and improve joint mobility and quality of life.