How long does splinting take to work for AC joint injury?

The acromioclavicular joint connects the collarbone to the shoulder blade. After a fall or blow, its supporting ligaments can be stretched or torn. A sling or other support limits painful shoulder movement and gives irritated tissues time to settle; it does not instantly repair a ligament or remove the visible bump that can occur after a separation.

Pain may ease before the shoulder is ready for lifting, pushing, reaching overhead, or contact activity. The injury grade, tenderness, strength, and shoulder stability influence the plan. A clinician may reassess movement before reducing support and starting exercises.

Wear the prescribed support as directed and check that it holds the arm comfortably without causing hand swelling, tingling, or colour change. Keep the elbow, wrist, and fingers moving if your clinician allows it, and protect the shoulder from sudden reaching or heavy loads.

Do not keep the shoulder completely still longer than advised, because stiffness can develop. Begin gentle shoulder exercises only when instructed, then build strength gradually. Ice wrapped in cloth may help short-term discomfort. Read more about [Splinting](/treatments/trauma-and-fracture-care/splinting/).

Seek prompt assessment if pain or swelling is getting worse, the skin becomes pale or blue, the hand feels cold or numb, or the support causes pressure marks. Get urgent care after a new fall, severe deformity, chest symptoms, or inability to move the fingers. Persistent weakness or pain despite the planned support period also warrants review.

Ask how long to wear the support, which shoulder movements are allowed, when exercises should begin, and what level of pain is expected. Clarify when you may drive, work overhead, lift, or return to sport, and whether a follow-up examination is needed.