What should you know about muscle pain between thumb and index finger?

The web space between the thumb and index finger contains small muscles, tendons, ligaments and joints that coordinate pinch and grasp. Repeated phone use, writing, tool handling, lifting or a sudden force can irritate these tissues. De Quervain’s tenosynovitis affects tendons on the thumb side of the wrist and may cause pain with thumb movement, gripping or lifting; the exact tender area can vary.

A clinician may examine thumb range, pinch strength, wrist movement and tenderness, then compare the other hand. A fall, visible deformity or sudden loss of movement raises concern for a more significant injury.

Reduce gripping, forceful pinching and repetitive thumb movements for a short period while keeping nearby joints gently mobile. Use a cool pack wrapped in cloth after an activity flare, or warmth if stiffness is the main problem. A thumb-supporting splint may reduce strain, but it should not cause numbness, colour change or worsening pain. Change how you hold devices and tools, and return to tasks gradually. A physiotherapist or hand specialist can guide exercises once the painful movement is understood.

Arrange an assessment if pain persists, repeatedly returns, or limits opening jars, dressing or work. Seek prompt care after a fall or twist if there is marked swelling, bruising, deformity, inability to move the thumb, or loss of feeling. Urgent review is also needed if the hand becomes unusually pale, blue or cold, or if pain is severe and rapidly worsening.

Ask which tissue seems irritated, whether a splint is suitable, how long to modify gripping, and which thumb exercises can restore strength without provoking symptoms.