Diagnostic sensitivity of ultrasound of the supraspinatus tendon when compared to magnetic resonance imaging prior to arthroscopy: A retrospective study

Introduction: Ultrasound (USS) and magnetic resonance imaging (MRI) have been used as screening tools for rotator cuff tears with MRI reported as superior. When comparing USS and MRI for supraspinatus tears, less data is available. Aim: Compare the diagnostic sensitivity of USS and MRI in the pre-operative diagnosis of partial thickness tears (PTT) and full thickness tears (FTT) of supraspinatus tendons compared to gold-standard shoulder arthroscopy to assess if differences in detection rates exist. Method: Retrospective study of deidentified electronic medical records including post-operative surgical notes and pre-operative imaging USS and MRI results. Results: N = 103 participants, male: female ratio of 63:40, mean age 64 years. FTT were diagnosed by arthroscopy in 63/103 (61.2%), PTT 5 mm in 22/103 (21.4%). USS and MRI sensitivity were both 95.2% for FTT. PTT 5 mm sensitivity were 73.3% and 86.4% respectively. Overall supraspinatus tears USS sensitivity was 88.4% and MRI 90.3%. Discussion: Comparable sensitivity was demonstrated for FTT for USS and MRI. USS had better sensitivity than MRI for PTT 5 mm. Pre-operative evaluation of suspected supraspinatus tears could include USS as a first line imaging modality, due to its low cost and easier availability. Conclusion: USS has high diagnostic accuracy for diagnosing supraspinatus FTT and PTT. MRI may be used where significant glenohumeral joint osteoarthritis needs to be assessed. Further studies with larger numbers are needed to verify these results