Swan Neck Deformity
Swan neck deformity is a finger or thumb tendon imbalance. The condition causes the middle finger joint to hyperextend and the fingertip joint to bend downward.
What You Need To Know About Swan Neck Deformity
What is Swan Neck Deformity?
Swan neck deformity is a degenerative condition most commonly found in the thumb that causes the thumb tip joint (called the IP joint) to bend and the middle thumb joint (called the MCP joint) to hyperextend. These unbalanced forces result in the condition's characteristic swan-neck appearance.
Swan neck finger is often associated with rheumatoid arthritis and other conditions that cause stiff joints and weak muscles. If the thumb tip joint bends but the middle thumb joint does not hyperextend, this is sometimes called a duck-bill thumb deformity. Patients with swan neck deformity experience difficulty extending and bending their finger joints.
Finding swan neck deformity treatment starts with a visit to Resurgens Orthopaedics. Schedule an appointment with one of our Atlanta-area experts now!
What Causes Swan Neck Deformity?
Swan neck deformity is often linked to rheumatoid arthritis which weakens or ruptures the surrounding structures. In patients with rheumatoid arthritis, swan neck deformity is caused by synovitis and tissue inflammation of the PIP joint (the middle finger joint). The joint tissues weaken, allowing the joint to hyperextend and the lateral stabilizing tendons shift above the joint axis.
As this shifting occurs, the flexor tendons become inflamed, causing the finger to flex at the MCP joint (The middle thumb joint). The shifting and inflammation effectively shortens the extensor tendons, increasing the stress on the PIP joint (the middle finger joint) and causes the DIP joint (the fingertip joint) to flex.
Other possible causes of swan neck deformity causes include:
a hyperextension injury to the PIP joint
a mallet finger injury in a patient with loose ligaments
muscle imbalance
an improperly-healed finger fracture
cerebral palsy
Swan Neck Deformity Symptoms
There are many swan neck finger symptoms. Often, the only symptom of swan neck deformity is the deformity itself — hand function may not be affected. Some patients experience stiffness when bending or flexing the middle joint. The tendons may snap as the finger is flexed, affecting the ease of movement in the joint. At times, this tendon snapping may become painful.
As the deformity becomes more advanced, it may be difficult or impossible to flex the fingers into a fist, and arthritis in the fingers may cause joint pain.
How is Swan Neck Deformity Diagnosed?
Resurgens Orthopaedics hand experts can recognize and diagnose a swan neck deformity through a simple examination. Your physician will ask a series of questions about the occurrence of your deformity and any pre-diagnosed conditions (such as arthritis) that may have contributed to the condition.
To test your range of motion, your physician may ask you to extend and bend your affected finger. This may cause some irritation in the joint.
Swan Neck Deformity Treatment
Swan neck deformity treatment may vary depending on the severity of the symptoms. If the deformity is painless and does not affect the function of the hand, patients may avoid treatment altogether. In other cases, specialized splints can prevent hyperextension and relieve snapping tendon discomfort. In more severe cases, surgery will be necessary to stabilize or fuse the joint.
Non-Surgical Treatment
The initial stages of swan neck deformity rarely require surgery. Many conditions are treated with physical therapy, stretches, and splinting. In some cases, a metal ring is placed around the joint to steady the joint and regulate movement.
Surgical Treatment
In severe cases of swan neck deformity, patients may require surgery to restore certain functions to the fingers. Recommended surgeries for this affliction include joint repositioning, tendon relocation, and occasional fusing of the joints.
Contact Resurgens Hand & Wrist experts today to learn more about swan neck deformity. Our physicians want to help estore ease of motion and comfort to our patients with aching joints. Schedule your appointment with Resurgens Orthopaedics now!