Ulnar Drift in Rheumatoid Arthritis and Other Diseases

​Ulnar drift (a.k.a. ulnar deviation) is a deformity of the hand that occurs when your knuckles—called the metacarpophalangeal (MCP) joints—become swollen and cause your fingers to bend abnormally toward the ulna bone on the outermost side of your forearm. Ulnar drift is most commonly associated with rheumatoid arthritis (RA) but can occur in other inflammatory diseases, as well.

The distortion caused by ulnar drift can be painful, aesthetically undesirable, and, over time, can make it hard for you to perform daily tasks that require gripping—such as opening a jar, twisting a doorknob, or using a zipper.

Symptoms of Ulnar Drift

Swelling of the knuckles is the main symptom of ulnar deviation. Other signs and symptoms include:

• Loss of ability for the thumb to oppose the index finger
• Warmth in your wrist, hand, and finger joints
• Pain or tenderness in the hand
• Inability to fully flex your fingers or make a fist
• Tightness and stiffness in the hand

Causes

With rheumatoid arthritis, chronic inflammation of the MCP joints damages the joint capsule and surrounding structures, which can result in ulnar drift.

It may also occur with other inflammatory conditions or connective tissue diseases, such as lupus or psoriatic arthritis. Research has also revealed an association with an uncommon disorder known as pigmented villonodular synovitis (PVNS), a disease in which the tissue lining your joints and tendons (synovium) grows abnormally.

Osteoarthritis can also result in ulnar drift. With this condition, joint cartilage wears away due to overuse or age rather than being damaged by autoimmune disease. Eventually, your bones start to rub together, damaging the joints and potentially causing them to become bent and distorted.

Diagnosis

Ulnar drift is usually evident from an examination of your hand. Your medical history will also be considered.

To measure the severity of ulnar drift, healthcare providers use a device called a goniometer. The stationary arm of this tool is placed over the metacarpal (the finger bone that connects the knuckle to the hand) while the movable arm is placed parallel to the proximal phalanx (the bone extending upward from the knuckle).

After the healthcare provider gets a measurement, they'll usually ask you to straighten your hand as much as possible to actively correct the alignment, and then take a second measurement.

Your healthcare provider may also use other hand-function tests and X-rays to get more information about bone and tissue damage as well as deformity.

If an underlying disease such as rheumatoid arthritis or lupus is suspected, but not yet diagnosed, blood tests may be used to investigate further.

Treatment

There is no cure for ulnar drift, which tends to progress over time. Lifestyle changes, exercises, therapies, and interventions can help ease discomfort and potentially slow progression.

Lifestyle Changes

The following lifestyle changes can help you avoid too much strain on your joints, which can worsen symptoms of ulnar drift:

• Use both hands to lift and hold heavy objects.
• Avoid using the handles on objects such as pots or coffee mugs (use oven mitts for hot objects).
• Try to avoid doing too many activities that move your fingers in the ulnar direction, such as opening jars or using doorknobs (keep internal doors cracked, for example).

Talk to your healthcare provider if you're finding it hard or painful to complete routine manual tasks. They may be able to recommend assistive devices to make things easier.

Hand Exercises

Hand exercises, which primarily involve stretching, are recommended to preserve range of motion as much as possible. Physical activities that put undue pressure or stress on the hands, such as planks or riding a bicycle (which requires gripping the handlebars) should be avoided.

Splinting

Splinting is sometimes recommended to properly position the MCP joints, relieve pain, and possibly slow disease progression. Generally, splints are worn at night or during rest periods in the daytime.

These types of splints may help slow disease progression:

• MCP joint splints, which you can wear during the day to support your fingers and help you grip objects with less pain
• Hand-resting splints, which are usually worn at night on your wrist and fingers to relax your MCP joint and reduce inflammation and pain
• Exercise splints, which support your MCP joint when you extend or flex your fingers to help reduce joint tightness or inflammation

Medications and Therapies

Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and naproxen can relieve pain.

Other options for treating hand swelling and pain include:

• Ice
• Moist heat
• Paraffin wax baths
• Transcutaneous electrical nerve stimulation unit, or TENS unit
• Ultrasound therapy

Surgery

Metacarpophalangeal (MCP) arthroplasty is a surgical method of improving pain, alignment, and function in people with ulnar drift. The procedure involves replacing painful knuckle joints with artificial knuckle joints.

For eight to 12 weeks after the surgery, patients wear hand splints and perform exercises to maintain and increase motion in the healing hand. This is known as post-operative therapy.