Acromial Types 各種形狀的 Acromion

Reference 本文出處:  https://radiopaedia.org/articles/acromial-types

The shape of the acromion had been initially divided into three types (which was known as the Bigliani classification) ³, to which a fourth has been added ². They are useful as a standardised way of describing the acromion, as well as predicting to a degree the incidence of impingement.
Acromion其實一開始有分三種型式，後來才加上了第四種。如此的分類在臨床上的使用，使其是能夠將之標準化後，變得在看 Impingement syndromes 能夠更有效地去推測。

分類
Classification

This classification was initially proposed by Bigliani et al in 1986 on outlet view radiographs, and later modified by Kitay et al ⁷ and Vanarthos et al in 1995, which remains the most widely accepted classification at time of writing (July 2016).
Acromion morphology (types) are based on sagittal oblique MRI:

如此的分類方法一開始是由 Bigliani 於1986年所提出的。之後也曾經在1995年被Kitay et al ⁷ and Vanarthos 等學者重新修訂過，也是最廣泛被使用且接受的。Acromion 的形體學是要在MRI 的sagittal oblique 的角度之下才看得出來。

http://musculoskeletalkey.com/wp-content/uploads/2016/06/F000055f005-008-9781455709779.jpg

1. flat inferiorly (12%) ⁶
2. curved (56%)
   • parallel to the humeral head with a concave undersurface 
   • considered most common type ³
3. hooked (29%)
   • the most anterior portion of the acromion has a hooked shape
   • associated with increased incidence of shoulder impingement
4. convex (upturned) (3%)
   • most recent classification of acromion process shape
   • the undersurface of the acromion is convex near the distal end ⁴
   • no convincing correlation between a type 4 acromion and impingement syndrome exists ^{4, 5}