Abstract
Objective Rotator cuff tendon tears are the most common soft tissue injuries in the shoulder
joint. Various animal models have been described for this condition, but all current
translational animal models have inherent weaknesses in their ability to generate
chronically degenerated rotator cuff tendons. The objective of this study was to evaluate
a partial infraspinatus tendon transection model as a means of creating a chronically
degenerated rotator cuff tendon in an ovine model and compare the injury characteristics
of this model to those observed in human patients with severe chronic rotator cuff
tendon injuries.
Study Design The infraspinatus tendons of six sheep were partially detached followed by capping
of the detached medial section of the tendon with Gore-Tex. Human tissue samples of
the supraspinatus tendon were harvested from patients undergoing primary reverse shoulder
arthroplasty and served as positive controls of chronic rotator cuff tendinopathy.
Results Transected sheep tendons were characterized predominantly by an acute reactive and
reparative pathological process as compared with the chronic degenerative changes
observed in the human tendons. In contrast, the non-transected portion of the ovine
tendon showed histological changes, which were more chronic and degenerative in nature
when compared with the transected tendon.
Conclusion Overall, histological features of the non-transected portion of ovine tendon were
more similar to those observed in the chronic degenerated human tendon.
Keywords
chronic rotator cuff degeneration - histopathology - preclinical model - sheep - supraspinatus
tendon
