Question

question 22 (mandatory) (2.5 points)
whats the total motion that takes place in the glenohumeral joint during full arm abduction?
a) 90 degrees
b) 60 degrees
c) 120 degrees
d) 180 degrees

Explanation:

The glenohumeral joint (shoulder joint) contributes approximately 90 - 120 degrees of motion during full arm abduction. However, when considering the total motion of the glenohumeral joint alone (not including scapulothoracic motion which adds to the full arm abduction), the typical range is about 90 degrees. But wait, no - actually, during full arm abduction (scapulothoracic motion + glenohumeral motion), the total arm abduction is 180 degrees. But the question is about the glenohumeral joint's contribution. Wait, no - the glenohumeral joint can move 90 - 120 degrees in abduction. But if we consider the pure glenohumeral motion (not combined with scapular movement), the answer is 90 degrees. Wait, no - actually, the glenohumeral joint can move 90 degrees in the plane of the scapula (scaption) and 120 degrees in the frontal plane (abduction). But if we consider the standard anatomical position for abduction (frontal plane), the glenohumeral joint contributes 90 degrees (the remaining 90 degrees comes from scapulothoracic motion). But wait, no - no, the glenohumeral joint can move 90 - 120 degrees. Wait, no - the glenohumeral joint's abduction range is 90 - 120. But if we consider the total motion of the glenohumeral joint during full arm abduction (assuming full arm abduction is 180, but that's combined). Wait, no - the question is about the glenohumeral joint's motion. The glenohumeral joint can move 90 degrees (some sources say 90 - 120, but if we take the lower bound as the typical answer for this type of question). Wait, no - actually, the glenohumeral joint's abduction is 90 degrees (in the frontal plane). The scapulothoracic joint adds another 60 - 90 degrees. But if the question is about the glenohumeral joint alone, the answer is 90 degrees.

Answer:

A. 90 degrees