Abstract
The proximity of neural structures to the coracoclavicular ligaments limits the amount of coracoid process that can be harvested. The purpose of this study of 100 dry human scapulae was to define the anatomic limitations.
We found the mean measurement of the horizontal arm of the coracoid process anterior to the conoid tubercle was 21.5 mm (SD 0.9 mm). In 10% of the scapulae, it was larger than 30 mm. In 66%, the posterior aspect of the conoid fused with the vertical ramus and the lateral lip of the suprascapular notch.
This amount of coracoid appears to be large enough to expand the glenoid vault, and to hold two AO small fragment screws. It can be safely harvested if the conoid ligament is respected. Partial sacrifice of the trapezoid ligament is unavoidable, but does not compromise coracoclavicular stability. If the coracoid osteotomy is extended medial to the conoid tubercle it encroaches on the vertical ramus of the coracoid and can damage the suprascapular nerve. Posterior advancement of the osteotomy can extend onto the anterosuperior glenoid.
The abstracts were edited by Prof. M.B.E. Sweet. Correspondence should be addressed to him at the Department of Orthopaedic Surgery, Medical School, University of the Witwatersrand, 7 York Road, Parktown, 2193 South Africa