What should you know about interphalangeal joint thumb pain?

The interphalangeal joint is the hinge between the thumb's two finger bones, closer to the tip than the thumb base. Pain after bending or impact may reflect a sprain, small fracture, or joint irritation. Repetitive gripping can overload the joint and nearby tendons. De Quervain's tenosynovitis usually affects tendons on the thumb-side of the wrist rather than this hinge, although pain can be felt along the thumb. A crooked appearance, locking, or inability to straighten the tip changes the urgency.

Rest from forceful gripping, pinching, and repeated thumb tapping. Keep the hand elevated if it is swollen, and use a cool pack wrapped in cloth for short periods. Do not force a stiff joint or try to straighten a visibly deformed thumb. A clinician may recommend temporary support, an examination, and imaging depending on the injury. Once serious injury is excluded, gentle range-of-motion work can help prevent avoidable stiffness.

Arrange prompt assessment after a fall, crush, or bend injury if pain is substantial, swelling persists, or movement is limited. Seek urgent care for an open wound, marked deformity, a pale or blue fingertip, or numbness. Ongoing pain, warmth, or swelling without a clear injury also deserves review, especially when everyday gripping becomes difficult.

Ask whether the joint, tendon, or ligament is affected; whether an X-ray or other test is needed; how long to support the thumb; and which exercises are safe during recovery.