Pain on the outside of the wrist, known as ulnar-sided wrist pain, is common because the wrist is a complex joint frequently subjected to twisting motions and repetitive strain. The ulnar side contains cartilage, tendons, and ligaments, which are vulnerable to injury from acute trauma or cumulative wear. Understanding the precise source of the pain requires identifying which specific structure is affected.
Triangular Fibrocartilage Complex (TFCC) Injuries
The most frequent source of ulnar-sided wrist pain is damage to the Triangular Fibrocartilage Complex (TFCC). The TFCC acts as a load-bearing shock absorber, cushioning the carpal bones and stabilizing the joint between the radius and ulna. It allows the wrist to move smoothly, including rotation and side-to-side movements.
Injuries often result from an acute event, such as a fall onto an outstretched hand, or a sudden, forceful twist. Repetitive, high-impact activities like racket sports can also cause chronic tears. When the TFCC is compromised, patients often report a clicking, popping, or catching sensation within the joint.
Pain is typically felt during specific actions, such as rotating the forearm or bearing weight on the hand. This is often accompanied by weakness or decreased grip strength. While many stable injuries heal with non-surgical management, recovery can be prolonged.
Extensor Carpi Ulnaris (ECU) Tendon Problems
Another common cause of pain involves the Extensor Carpi Ulnaris (ECU) tendon, which runs along the pinky-finger side of the forearm and wrist. The ECU tendon’s primary function is to help straighten the wrist and move the hand toward the pinky side (ulnar deviation). Problems with the ECU are categorized as either inflammation (tendonitis) or instability (subluxation).
ECU tendonitis develops from overuse or repetitive strain, often seen in racket sports or tasks involving repetitive wrist movements. Symptoms include tenderness and swelling localized over the tendon, and increased pain when the wrist moves toward the pinky side.
ECU subluxation occurs when the tendon snaps or slides out of its normal groove on the ulna bone. This instability results from a traumatic injury that damages the sheath holding the tendon in place. Patients report a painful snapping or clicking sensation with specific twisting movements, particularly when turning the hand palm-up.
Chronic Bone and Joint Conditions
Chronic bone and joint conditions are less common but can be persistent sources of ulnar-sided wrist pain. These issues involve long-term changes to the bone structure or joint surfaces, often leading to a dull, aching discomfort.
One condition is Ulnar Impaction Syndrome, which occurs when the ulna bone is relatively longer than the radius bone in the forearm. This length difference causes the ulna to prematurely contact and excessively load the TFCC and carpal bones during movement. The resulting friction and pressure lead to progressive degeneration and cartilage wear.
Pain from Ulnar Impaction Syndrome is typically a chronic ache aggravated by heavy gripping or twisting activities. Localized osteoarthritis can also affect the small joints where the ulna meets the carpal bones. Osteoarthritis generally presents as chronic pain that worsens with activity and may limit joint movement.
Immediate Relief and Medical Consultation
For immediate management of new or sudden wrist pain, initial care should focus on reducing inflammation and preventing further strain. Applying the R.I.C.E. principles—Rest, Ice, Compression, and Elevation—can help manage swelling and discomfort. Applying ice packs to the painful area for 10 to 15 minutes several times a day is often helpful.
Over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can relieve pain and inflammation. It is important to avoid activities that reproduce the pain, especially twisting or heavy gripping. If pain persists beyond a few days or symptoms are severe, medical evaluation is necessary.
Professional medical attention is required if there is a visible deformity, severe and sudden pain, or an inability to move the wrist. Concerning symptoms also include numbness or tingling in the fingers, which may indicate nerve involvement.
A physician will perform a physical examination, often involving specific wrist movements to reproduce symptoms. They may order imaging tests like X-rays to check for bone issues or an MRI to visualize soft tissues like the TFCC and tendons.