Ligament · Shoulders

Sternoclavicular ligament

Ligamentum sternoclaviculare

The front and back thickenings of the capsule where the collarbone meets the breastbone — the only place in the skeleton where the arm is joined to the trunk by bone. The two bony surfaces fit each other poorly and a disc of fibrocartilage sits between them, so nearly all the strength of the joint comes from ligament, and this pair is the front and back of that arrangement. The posterior fibres are the stronger of the two, which matters given what lies immediately behind them: the great vessels at the root of the neck.