Changes of the mineralization pattern in the subchondral bone plate of the glenoid cavity in the shoulder joints of the throwing athletes.

The distribution of mineralization in the subchondral bone plate (DMSB) is used as a parameter for individual stress distribution of shoulder joints. We have analyzed 28 shoulder joints of throwing athletes by DMSB of the glenoid with computed tomography osteoabsorptiometry and described their mineralization patterns. The throwing motion imposes a heavy rotational load on the shoulder joint, and this, in turn, may lead to excessive translation of the humeral head on the glenoid. This could explain why the two most frequent density maxima were localized to the anterior and posterior portions of the glenoid. Our finding of a frequent bicentric density distribution of the shoulder joints of throwing athletes should be useful in any future analysis of the relationship between the DMSB and the bone morphology of the glenoid.