A dislocation occurs when a bone is pulled or pushed out of place (out of its normal relationship to the other bones that make up a joint). This can happen in joints such as the kneecap, hip, finger, elbow, or shoulder.

A dislocation may be caused by a direct blow to the joint, a fall, or a sudden twisting movement. Everyday activities may cause this injury if a person has unstable joints.

A dislocation can be a problem even if the bone pops back into place.

• Soft tissues in or around a joint (such as ligaments, tendons, muscles, cartilage, and the joint capsule) may stretch or tear.
• Nerves and blood vessels may be damaged by the injury.
• A piece of bone at the base of the joint may break off and end up inside the joint or cause a fracture that extends into the joint.