Conclusion
In this case report, we propose a novel biomechanical source of internal
impingement: direct impingement of the biceps tendon on the undersurface
of the supraspinatus tendon. We believe that impingement of the LHB can
either directly lead to, or potentially aggravate, articular-sided tears
of the supraspinatus tendon. This proposed mechanism of impingement may
help explain why debridement alone can produce suboptimal results
[10,14,13]. In cases where pain persists despite arthroscopic
debridement, we recommend performing a biceps tenodesis. In addition, we
recommend taking the arm out of traction during arthroscopy and placing
it in the 90-90 position. If the biceps tendon can be seen directly
abrading the supraspinatus tendon, we recommend primary biceps
tenodesis.