Acute shoulder injury (non traumatic) 6 weeks ago with pain and weakness that was made worse by repetitive injury 3 weeks ago. Primarily Weakness and pain on extension from 20-60 degrees with elbow in 90 degress flexion. Rotation is strong and non painful abduction is strong with mild pain. MRI shows near full thickness tear of INFRASPINATUS tendon. Surgeon recommending surgical repair due ot high risk of progression.
My question is, the MRI findings dont seem to correlate well with my exam. Isnt infrspinatus primary needed for rotation of the shoulder?