Rotator cuff repair (RCR) is a crucial surgical procedure, but has unacceptable mechanical failure rates between 25–60%. Examining supplemental synergistic interventions, such as biological augmentations (ex: growth factors) to improve fibrocartilage formation rather than scar tissue formation, would make tears more amenable to surgical repair. Due to the large number of agents and application methods (and times), improved techniques are needed for assessing RCR in animals. In particular, high-resolution real-time imaging is needed to guide tissue engineering in animal models. Optical coherence tomography (OCT) is well suited for this role, with resolutions 25 × greater than any clinical imaging modality and an ability to identify organized collagen with polarization sensitive techniques. For example, it can determine severe collagen depletion in visually normal tendons. The images here show the first OCT and PS-OCT of the rotator cuff in male Wistar rats. The structure of the supraspinatus tendon, enthesis, and humerus are well defined. For histological comparison, this sample was stained with both Masson's Trichrome, to expose any structural abnormalities, and Picrosirius Red, to determine collagen content using a polarization filter. OCT studies offer the potential of understanding RCR failure mechanisms and potential tissue altering agents, substantially impacting outcomes.
Experimental Methods to Simulate and Evaluate Postsurgical Peripheral Nerve Scarring
