What is a Type 3 acromion configuration?
If you have a Type III or “hooked” acromion, you are more predisposed to shoulder impingement. Secondly, weakness in your posterior cuff (infraspinatus/teres minor) can cause abnormal shoulder mechanics leading to impingement.
What is a Type III acromion?
The type II acromion is more curved and downward dipping, and the type III acromion is hooked and downward dipping, obstructing the outlet for the supraspinatus tendon.3 Cadaveric studies have shown an increased incidence of rotator cuff tears in persons with type II and type III acromions.2,3. View/Print Figure.
How common is type 3 acromion?
The distribution of acromial types was as follows: type I, flat, 51 (12.1%); type II, curved, 239 (56.5%); type III, hooked, 122 (28.8%); and type IV, convex, 11 (2.6%).
How do you determine acromion type?
The acromial angle classification categorizes acromial shape as one of three types (Figure 2) (Toivonen et al. 1995) determined by two lines connecting the highest point both with the most anterior and the most posterior point of the acromial undersurface.
How long does impingement of the shoulder last?
Shoulder impingement usually takes about three to six months to heal completely. More severe cases can take up to a year to heal. However, you can usually start returning to your normal activities within two to four weeks. Just make sure you regularly check in with your doctor to make sure you aren’t overdoing it.
Is impingement syndrome chronic or acute?
The general pathology of subacromial impingment generally relates to a chronic repetitive process in which the conjoint tendon of the rotator cuff undergoes repetitive compression and micro trauma as it passes under the coracoacromial arch. However acute traumatic injuries may also lead to this condition.
How many types of acromion are there?
four types
The acromial shape can be classified into four types: type I (flat), type II (curved), type III (hooked) 4, 5, 6 and type IV (convex) (Fig. 1) (7).
How are magnetic resonance imaging used to study acromion?
The magnetic resonance imaging (MRI) makes it possible to depict the shape of acromion in its longitudinal axis with better evaluation of the acromial morphological factors including the acromial shape, acromial thickness, acromio-humeral distance, and lateral acromial angle and acromial index.
Which is more common type I or Type III acromion?
In a previous study done by Paraskevas, et al. (15) they noted that type-I acromion was significantly more common in females (13 or 56.5% vs. 10 or 43.4%), whereas type III was significantly more common in males (9 or 56.2% vs. 7 or 43.7% in females).
Which is the most accurate description of acromion morphology?
Acromion morphology (types) are based on sagittal oblique MRI: flat inferiorly (12%) 6 curved (56%) parallel to the humeral head with a concave undersurface hooked (29%) the most anterior portion of the acromion has a hooked shape convex (upturned) (3%) most recent classification of acromion process shape
How many types of acromial types are there?
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 used as a standardized way of describing the acromion, as well as predicting to a degree the incidence of impingement. Classification.
