抄録
The puropose of this study was to investigate the relation between the morphology of the acromion and the spur at the antero-inferior surface of the acromion. This investigation was performed on 268scapular dry bone specimens. These specimens of 107 males and 34 females were used. Their ages ranged from 20 to 83 years with an average of 57 years. The presence of spurs of the acromion were identified. All the acromions were classified as type I (flat), type II (curved) or type III (hooked) as described by Bigliani et al. The slope of the acromion was measured in all the spcimens, as well.
Spur at the antero-inferior surface was seen in 129 acromions(48.1% ). Almost all the spurs were located in the anterior one third of the acromion. In all the specimens, eighty-six acromions(32.1%)were type I, one hundred and thirty-nine(51.9%)were type II and forty-three(16.0%)were type III. The type of acromion was not related to whether there was the presence of a spur or not. The average slope of all the acromions was 47±8°, that of the acromions with a spur was 44±7°and that of the acromions without a spur was 50±8°. There was a significant difference between the slope of an acromions with a spur and one without a spur. From this study, we conclude that the type of acromion had no relation to a subacromial impingement and the flattened slope of the acromion might be one of the causes of a subacromial impingement.
