Objective: To compare potential differences in size and extent of labral tears on magnetic resonance arthrography of the shoulder performed with saline to shoulder to arthroscopy as the gold standard in adolescent patients with tears of the glenoid labrum. Materials and methods:Pre-operative saline magnetic resonance arthrograms of the glenoid labrum were assessed by two radiologists for location and extent of the labral tear based on the clock-face method of visualization. The radiology findings were compared to the surgeon's recorded arthroscopic findings (the start and end of the labral tear based on the clock-face method and the total range) in the operative report. One-way analysis of variance was used to compare saline magnetic resonance arthrograms and arthroscopic findings.Results: Sixteen shoulder saline magnetic resonance arthrograms were included (15 underwent unilateral arthroscopic labral repair, 1 underwent bilateral arthroscopic labral repair. Most patients were male with an average of 17 years of age (range: 15-19 years) at the time of surgery. On average, 54 days elapsed between pre-operative imaging and surgery (range: 9-204 days). Both raters agreed that 100% of the examinations were of diagnostic quality. There were no significant differences between surgical report and the magnetic resonance arthrography raters for the mean clock face start (p = 0.47), end (p = 0.67), or total range of the tear (p = 0.97). The mean range of the tear was 4 hours for all three raters. Conclusion:Saline contrast for magnetic resonance shoulder arthrography in adolescent patients is a reliable imaging technique when evaluating the glenoid labrum for the location and extent of injury and is a prudent alternative to gadolinium based contrast agents in adolescent patients.