• PURPOSE
    • Posteromedial olecranon impingement (PMOI) is the most common diagnosis in baseball players with throwing-induced elbow injuries. CT imaging manifestations of PMOI have seldom been previously reported. Our purpose is to investigate the additional value of CT imaging in the evaluation of PMOI.
  • MATERIALS AND METHODS
    • From July 2010 to December 2013, 47 baseball players with throwing-induced elbow pain received imaging studies (CT and/or MRI) of the elbow at our institution. After retrospectively reviewing the clinical records and imaging studies, 31 of the 47 players were diagnosed with PMOI by the criteria of posteromedial elbow pain with clinical consistency for PMOI and characteristic osteoarthrosis at the posteromedial ulnotrochlear articulation (posteromedial olecranon space, PMOS) detected by CT and/or MRI. The imaging modalities of these 31 players including radiography, CT, and MRI were reviewed by 2 experienced musculoskeletal radiologists.
  • RESULTS
    • The most common imaging manifestations of PMOI by CT or MRI include joint space narrowing, subchondral sclerosis, and osteophytes at the PMOS. CT was superior to MRI with a statistically significant (P<0.05) difference in detecting joint space narrowing, medial olecranon subluxation, as well as the number of loose bodies. In contrast, bone marrow edema and associated soft tissue injuries in PMOI are more readily observed on MRI.
  • CONCLUSIONS
    • CT is superior in identifying some imaging features of PMOI. Whenever PMOI is diagnosed in the pitching elbow of a baseball player, CT should be considered prior to surgical intervention as it will often provide additional information to the surgeon that may alter surgical management.