Ching-Chung Ko MD, Presenter: Nothing to Disclose

Kuen-Huang Chen MD, Abstract Co-Author: Nothing to Disclose

Jeon-Hor Chen MD, Abstract Co-Author: Nothing to Disclose

Wen-Sheng Tzeng MD, Abstract Co-Author: Nothing to Disclose

Ginger Shu, Abstract Co-Author: Nothing to Disclose

Chung-Da Wu, Abstract Co-Author: Nothing to Disclose

Posteromedial olecranon impingement (PMOI) is the most common diagnosis in the baseball players with throwing-induced elbow injuries. Imaging manifestations of PMOI have seldom been reported before. We aimed to investigate imaging features of PMOI with emphasis on CT and MRI, and compare the imaging findings in these two modalities.

From July 2010 to February 2013, imaging studies of the elbow joints from 24 baseball players are reviewed by an experienced musculoskeletal radiologist. All of these players had elbow pain when throwing and decreased range of motion in the elbow joint. All subjects are male with a mean age of 17.6 years (range, 12 to 31 years). The mean duration of playing baseball was 8 years (range, 3 to 19 years). The dominant arm was affected in all patients. The imaging modalities for evaluating PMOI include plain film (n=24), CT (n=12), MRI (n=24).

The imaging findings by CT or MRI include PMOI (n=20, 83%), injury of ulnar collateral ligament(UCL) (n=15, 63%), avulsion fracture of medial epicondyle(ME) (n=10, 42%), osteochondritis dissecans(OCD) (n=7, 29%), stress fracture of olecranon process (n=5, 21%), and ulnar neuritis (n=1, 4%). The findings in the plain film include osteophytes, loose bodies, and stress fracture of olecranon process. In the 20 players with PMOI findings, 10 players received CT and MRI studies simultaneously. The imaging manifestations in CT studies of these 10 players include cartilage space loss (n=10, 100%), subchondral sclerosis (n=10, 100%), osteophytes (n=10, 100%), OCD (n=4, 40%), and stress fracture of olecranon process (n=4, 40%). As compared with CT, the MRI showed lower sensitivity in detecting PMOI findings such as cartilage space loss, osteophytes, and OCD. The MRI is good in detecting associated findings of PMOI like UCL injury (n=7, 70%) and bone marrow edema (n=6, 60%) in these 10 players, which cannot be evaluated by CT because of poor image resolution. The most common associated findings of PMOI in this study are UCL injury (n=15, 75%) and avulsion fracture of ME (n=9, 45%).

Although CT is more sensitive for detecting PMOI, MRI is necessary for evaluating associated injuries. In patients diagnosed with PMOI and need surgical intervention, CT offers fast and helpful information.  

CT is a good choice in evaluating PMOI and could be used before surgical intervention in patients diagnosed with PMOI previously.

Ko, C, Chen, K, Chen, J, Tzeng, W, Shu, G, Wu, C, Posteromedial Olecranon Impingement: CT and MR Imaging Findings of Pitching Elbow.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13018561.html