title: Comparative analysis of anterior and posterior contrast injection approaches for shoulder MR arthrograms in adolescents.
abstract: BACKGROUND
  There is no consensus in the literature concerning the optimal approach for performing a fluoroscopically guided shoulder arthrogram injection in a pediatric population.
  
  
  OBJECTIVE
  To compare adequacy of capsular injection and radiation doses between fluoroscopically guided anterior and posterior glenohumeral joint contrast injections in adolescents.
  
  
  METHODS
  We evaluated imaging in 67 adolescents (39 boys, 28 girls; mean age 16.0 years; range 11.7-19.1 years) who underwent an anterior approach glenohumeral contrast injection with subsequent MR imaging, and 67 age- and gender-matched subjects (39 boys, 28 girls; mean age 16.0 years; range 11.1-19.2 years) who underwent a posterior approach injection during the period June 2010 to September 2015. Two pediatric radiologists independently evaluated all MR shoulder arthrograms to assess adequacy of capsular distention and degree of contrast extravasation. We recorded total fluoroscopic time, dose-area product (DAP) and cumulative air kerma (CAK).
  
  
  RESULTS
  There were no significant differences in age, gender, height, weight or body mass index between the populations (P-values > 0.6). The amount of contrast extravasation between the groups was not significantly different (P = 0.27). Three anterior injections (4.5%) and one posterior (1.5%) were suboptimal (P = 0.62). Fluoroscopy time was not different: 1.1 min anterior and 1.3 min posterior (P = 0.14). There was a significant difference in CAK (0.7 mGy anterior and 1.1 mGy posterior; P = 0.007) and DAP (5.3 μGym2anterior and 9.4 μGym2posterior; P = 0.008). Inter-rater agreement was excellent (Cohen kappa >0.81).
  
  
  CONCLUSIONS
  Both techniques were technically successful. There was no difference in the fluoroscopy time for either approach. The radiation dose was higher with the posterior approach but this is of questionable clinical significance.
authors: Division of Interventional Radiology, Department of Radiology, The Children's Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, PA, 19104, USA. ted.gupton@gmail.com.
authors: Theodore B
authors: TB
authors: Gupton
authors: Department of Radiology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
authors: Jorge
authors: J
authors: Delgado
authors: Diagnostic Radiology, Stanford University Medical Center, Palo Alto, CA, USA.
authors: Diego
authors: D
authors: Jaramillo
authors: Division of Interventional Radiology, Department of Radiology, The Children's Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, PA, 19104, USA.
authors: Anne M
authors: AM
authors: Cahill
authors: Musculoskeletal Imaging, Department of Radiology, The Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors: Nancy A
authors: NA
authors: Chauvin
mesh_terms: D000293:Adolescent; D001175:Arthrography / Q000379:methods*; D016022:Case-Control Studies; D003287:Contrast Media / Q000008:administration & dosage*; D005119:Extravasation of Diagnostic and Therapeutic Materials; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007270:Injections, Intra-Articular; D008297:Male; D011829:Radiation Dosage; D012189:Retrospective Studies; D000070599:Shoulder Injuries; D012785:Shoulder Joint / Q000000981:diagnostic imaging*; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Adolescents; Fluoroscopy; Glenohumeral joint; Injection; Magnetic resonance arthrogram; Radiation dose; Shoulder