Ligamentous restraints to anterior and posterior translation of the sternoclavicular joint.

This experiment was conducted to determine the primary ligamentous restraints to anterior and posterior translation of the sternoclavicular joint. Twenty-four unpaired cadaver specimens were mounted in a custom fixture. Anterior and posterior translations were measured under a sub-failure load in the intact specimen and again after transecting one randomly chosen ligament (anterior capsule, posterior capsule, interclavicular ligament, and costoclavicular ligament; n = 6 for each group). Cutting the posterior capsule resulted in significant increases in anterior translation and posterior translation. Cutting the anterior capsule produced significant increases in anterior translation. Cutting the costoclavicular and interclavicular ligaments had little effect on sternoclavicular joint translation. The posterior capsule is the most important restraint for anterior and posterior translation of the sternoclavicular joint. The anterior capsule is another important restraint for anterior translation. The costoclavicular and interclavicular ligaments have little effect on anterior or posterior translation of the sternoclavicular joint.