title: Posteromedial olecranon impingement of the pitching elbow: Additional findings provided by CT.
abstract: OBJECTIVE
  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.
  
  
  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.
authors.affiliation: Department of Medical Imaging, Chi Mei Medical Center, No. 901, Zhonghua Rd., Yongkang District, Tainan City 71004, Taiwan; Institute of Biomedical Science, National Sun Yat-Sen University, Kaohsiung, Taiwan. Electronic address: crazyboy0729@gmail.com.
authors.forename: Ching Chung
authors.initials: CC
authors.lastname: Ko
authors.affiliation: Institute of Biomedical Science, National Sun Yat-Sen University, Kaohsiung, Taiwan. Electronic address: mhtai@faculty.nsysu.edu.tw.
authors.forename: Ming Hong
authors.initials: MH
authors.lastname: Tai
authors.affiliation: Department of Medical Imaging, Chi Mei Medical Center, No. 901, Zhonghua Rd., Yongkang District, Tainan City 71004, Taiwan. Electronic address: chienhark@yahoo.com.tw.
authors.forename: Chien Hung
authors.initials: CH
authors.lastname: Lin
authors.affiliation: Department of Medical Imaging, Chi Mei Medical Center, No. 901, Zhonghua Rd., Yongkang District, Tainan City 71004, Taiwan. Electronic address: tws4664@gmail.com.
authors.forename: Wen Sheng
authors.initials: WS
authors.lastname: Tzeng
authors.affiliation: Department of Radiology, I-Shou University and Eda Hospital, No. 1, Yi-Da Road, Jiau-Shu Tsuen, Yan-Chau Shiang, Kaohsiung County 824, Taiwan. Electronic address: jeonhc@uci.edu.
authors.forename: Jeon Hor
authors.initials: JH
authors.lastname: Chen
authors.affiliation: Department of Medical Imaging, Chi Mei Medical Center, No. 901, Zhonghua Rd., Yongkang District, Tainan City 71004, Taiwan. Electronic address: mariposa@seed.net.tw.
authors.forename: Ginger
authors.initials: G
authors.lastname: Shu
authors.affiliation: Department of Orthopaedics, Chi Mei Medical Center, No. 901, Zhonghua Rd., Yongkang District, Tainan City 71004, Taiwan. Electronic address: wcd@mail.chimei.org.tw.
authors.forename: Chung
authors.initials: C
authors.lastname: Da Wu
authors.affiliation: Department of Medical Imaging, Chi Mei Medical Center, No. 901, Zhonghua Rd., Yongkang District, Tainan City 71004, Taiwan. Electronic address: ckhc821@gmail.com.
authors.forename: Clement Kuen Huang
authors.initials: CKH
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D001484:Baseball / Q000293:injuries*; D015331:Cohort Studies; D004551:Elbow Joint / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007592:Joint Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D056740:Olecranon Process / Q000000981:diagnostic imaging* / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D055815:Young Adult; D000092464:Elbow Injuries
keywords: CT; MRI; Pitching elbow; Posteromedial olecranon impingement; Valgus extension overload