Zusammenfassung
Die Form des Akromions ist entscheidend mit dem Impingementsyndrom und Rotatorenmanschettenrissen assoziiert. Es ist nur allzu bekannt, daß sich das Akromion mit herkömmlicher Radiographie nur schwierig darstellen läßt. Wir haben MRI-Techniken entwickelt, die es erlauben, das Akromion in seiner longitudinalen Achse darzustellen. Des weiteren haben wir den Subakromialraum sowohl in Außen- als auch in Innenrotation gemessen. In früheren Studien wurden 3 Typen der akromialen Form beschrieben, wobei der Typ 3 bzw. das Hooked-Akromion in 66% der Fälle von Rotatorenmanschettenrissen vorkommt. Wir untersuchten 31 normale Schultern bei 29 Personen mit MRI. In dieser Population mit einem Alter von 24–36 Jahren, Mittelwert 31 Jahre, wurde kein Typ-III-Akromion gefunden. 21 (67,7%) Schultern waren dem Typ I und 10 (32,3%) dem Typ II zuzuordnen. Zudem fanden wir keien Unterschiede der subakromialen Höhe in Außen- und Innenrotation. Mit Kontrollstudien wurden niedrige Intra- und Inter-Observer-Fehler nachgewiesen. Diese Ergebnisse zeigen daß das Hooked-Akromion in der Normalbevölkerung nicht auftritt und es sich hierbei demzufolge um eine erworbene Abnormalität handelt.
Abstract
The shape of the acromion is strongly associated with impingement syndrome and with rotator cuff tears. It is notoriously difficult to image the acromion with conventional radiography. We have developed MRI techniques to depict the acromion in its longitudinal axis. Furthermore, we have measured the subacromial space in both external and internal rotation. In previous studies, three types of acromial shape have been described with the type III or hooked acromion being present in 66% of cases with rotator cuff tears. We studied 31 normal shoulders in 29 people using MRI. Within this population aged 24–36 years, mean age 31 years, no type III acromions were found. Twenty-one were type I (67.7%) and 10 were type II (32.3%). In addition, we found no difference in subacromial height in external or internal rotation. Low rates of intra- and interobserver error were found. These results imply that the hooked acromion is not present in the normal population and is, therefore, likely to be an acquired abnormality.
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Schippinger, G., Bailey, D., McNally, E.G. et al. Anatomy of the normal acromion investigated using MRI. Langenbecks Arch Chiv 382, 141–144 (1997). https://doi.org/10.1007/BF02498666
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DOI: https://doi.org/10.1007/BF02498666