Cyclical loading of coracoclavicular ligament reconstructions: a comparative biomechanical study.
BACKGROUND
Reconstruction for injuries to the acromioclavicular joint remains controversial.


OBJECTIVE
A coracoclavicular ligament reconstruction with a semitendinosus tendon would have superior performance to the classic coracoacromial ligament transfer with or without augmentation.


METHODS
Controlled laboratory study.


METHODS
Five cadaveric shoulders were used to reconstruct the coracoclavicular ligaments with 3 methods: coracoacromial ligament transfer without augmentation, coracoacromial ligament transfer augmented with No. 5 Ethibond suture, and a semitendinosus tendon. Each reconstruction was cyclically loaded at 40 N to 80 N for 2500 cycles, then from 40 N to 210 N for 2500 cycles, followed by loading to failure. The number of cycles to 50% and 100% loss of acromioclavicular joint reduction were recorded.


RESULTS
During the 40 N to 80 N-loading cycle, the coracoacromial transfer without augmentation failed (15 +/- 16 cycles). The augmented coracoacromial ligament transfer and the semitendinosus reconstruction did not fail (P = .008). During the 40 N to 210 N-loading cycle, the augmented coracoacromial ligament transfer failed (207 +/- 399 cycles). The semitendinosus reconstruction survived through both loading cycles (P < .01).


CONCLUSIONS
Coracoclavicular ligament reconstruction with a semitendinosus graft is a biomechanically superior construct in a cyclically loaded setting to a coracoacromial ligament transfer augmented with a No. 5 Ethibond suture.


CONCLUSIONS
The semitendinosus graft is a strong, biologic option for reconstruction of the coracoclavicular ligaments.
Lee
Steven J
SJ
Nicholas Institute of Sports Medicine and Athletic Trauma, Lenox Hill Hospital, New York, NY 10075, USA. sjleemd@aol.com
Keefer
Eric P
EP
McHugh
Malachy P
MP
Kremenic
Ian J
IJ
Orishimo
Karl F
KF
Ben-Avi
Simon
S
Nicholas
Stephen J
SJ
D000173:Acromioclavicular Joint / Q000502:physiology / Q000601:surgery*; D000328:Adult; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006801:Humans; D008023:Ligaments, Articular / Q000502:physiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D013709:Tendon Transfer; D013710:Tendons / Q000502:physiology / Q000637:transplantation; D016474:Weight-Bearing