Abstract
Purpose This study aimed to analyze the distance between the superior edge of the pectoralis
major and the top of the humeral head and evaluate whether this distance is a consistent
measurement.
Methods Twenty-two shoulders in eleven cadavers were dissected and the attachment of the
pectoralis major tendon was preserved. Two distances were recorded with the help of
digital vernier caliper: the distance between the upper edge of pectoralis major and
tangent to the top of humeral head (PM–T) and the distance between the superomedial
tip of greater tuberosity (GT) and the upper edge of the pectoralis major tendon (PM–G; ± standard
error of the means).
Results The mean PM–T distance was 53.8 mm (±0.8 mm) and the mean PM–G distance was 46.8 mm
(±0.9 mm). The distance between the top of humeral head and tip of the GT was 7 mm.
The PM–T distance was a significant outlier in three shoulders as it inserted high
on the humerus.
Conclusion We can conclude that the PM–T and PM–G distances were a consistent measurement.
Clinical Relevance The distance between the pectoralis major tendon and top of the humeral head was
measured in this study as a reliable method that can be used intraoperatively to decide
the height of the humerus prosthesis in comminuted fractures of the proximal humerus.
Keywords
cadaver study - shoulder hemiarthroplasty - pectoralis major - tendon insertion -
humeral head
