Interstitial tears of the rotator cuff: difficulty in preoperative diagnosis

Interstitial tears are difficult to diagnose before surgery because MRI findings may lead to the misdiagnosis of interstitial tears as articular- or bursal-sided tears. If MRI-based diagnosis is indicative of articular- or bursal-sided tears but arthroscopy reveals fibrillation and dimpling of the tendon surface, interstitial tears should be suspected. The defective sites in interstitial tears are usually accompanied by congestion.