Sternoclavicular (SC) joint seperation consists of ligament tearing to the joint connecting the breastbone [sternum] and the collarbone [clavicle].
There are two common mechanisms of injury. In the first, a direct blow or landing on the side of the body can indirectly load the SC joint, leading to disruption of the ligaments around the SC joint. Examples include a side-blow in a car accident or a pile-on in a football game.
Less commonly, a direct force to the collarbone (clavicle) near the joint or the sternum (breast bone) can also cause joint disruption.
Infection can erode the SC joint as well and is possible with instrumentation (surgical or otherwise) in that area and can occur in IV drug users.
If the clavicle is significantly posteriorly displaced, the situation can be urgent/emergent especially if peripheral pulses are compromised or there is significant breathing difficulty. With more chronic SC instability, there can be pain and grinding in the anterior chest by the collar bone.
Procedural options include cortisone injections to the SC joint for chronic pain resulting from SC sprain/separation. In the acute phase, cortisone is not recommended as it can impede healing. Regenerative-type injections (such as platelet-rich plasma [PRP] or stem cell injections) can theoretically provide longer lasting pain relief and improved function by stimulating the body’s own natural healing response when conventional treatments have failed.