Presentation
History of fall on outstretched arm, pain and immobility since then.
Patient Data
This x-ray was done after the arthroscopic surgery and cuff repair, however it does show the greater tuberosity fracture of the proximal humerus.
CT shows avulsion fracture of the greater tuberosity of proximal left humerus with minimal distraction.
This case clearly demonstrates a mildly displaced avulsion fracture of the greater tubercle of humerus, with marrow edema, and partially retracted subscapularis showing intramuscular hematoma. Also seen is insertion edema and partial tear of rotator cuff at supraspinatus tendon near the humeral foot plate. The myotendinous belly of supraspinatus shows fatty atrophy likely due to previous intrabursal injection or chronic subacromial impingement and tendinopathy. The infraspinatus and to a lesser extent teres minor insertions show minimal edema.
Well delineated is the humeral avulsion of inferior glenohumeral ligament (IGHL) with a positive J-sign, lamellated periosteal stripping at posteroinferior bony glenoid but no bony fracture. There is extrasynovial spill of joint effusion/hemarthrosis into the adjacent muscle planes secondary to capsular disruption.
Minimal free fluid is seen tracking along the deep pectoral fascia and bicipital tendon.
The HAGL lesion is evident on T2 fat sat with positive J sign, downward bellowing of IGHL with extrasynovial dissection of joint fluid into intramuscular planes.
Case Discussion
MRI reveals avulsion fracture of greater tuberosity of humerus with a HAGL lesion, intramuscular hematoma at subscapularis, and partial tear at supraspinatus and teres minor insertion.
This patient underwent arthroscopic repair and the above findings were confirmed. As per the surgeon, there was a tear at the insertion of infraspinatus.