Abstract:

BACKGROUND: Coracoclavicular ligament plays an important role in maintaining acromioclavicular joint (ACJ) stability, thus, ACJ reconstruction is necessary. 
OBJECTIVE: To observe the biomechanics of acromioclavicular joint reduction using triple button plates. 
METHODS: Fifteen fresh shoulders were collected, prepared for ACJ dislocation, and reconstructed using triple button plate or double Endobutton. Biomechanical stress analysis was used to compare performances and the effects of two methods.
RESULTS AND CONCLUSION: The stress-strain relationship showed that, strength of triple button plate was 25% and 15% larger than the normal coracoclavicular ligament and double Endobutton plate, the elastic modulus was 17% and 14%, and the axial stiffness was 24% and 14%, respectively. There were significant differences between the two groups (P < 0.05). Triple button plates are superior to initial ACJ in strength and stiffness. Obviously, triple fixed-button reconstruction has mechanical advantage than reconstruction plate has much mechanical advantage than the double Endobutton plate.