Rotator Cuff Repair
Development of a novel bone-tendon allograft procedure for the repair of the rotator cuff in a canine model
Dr Cook (PI) and Dr Jayabalan (Co-PI) are working on developing a novel surgical graft technique for the repair of the rotator cuff. Repair of chronic tears of the rotator cuff fail in 30-90% of cases. Current repair techniques do not re-establish normal bone-tendon (B-T) or tendon-muscle (T-M) junctions. Optimizing the strength and function at these junctions may result in lower failure rates with greater clinical success. Current graft techniques merely reinforce or augment tissue that is already present and are not ‘span’ or structural in nature. In addition the majority of grafts available are heterotopic allografts or xeonografts. Bone allografts provide the advantage of no untoward immune response and no frank rejection. Modern day ACL, meniscal and osteochondral surgeries incorporate bone allografts and tissue networks could provide the necessary materials.
We developed a bone-tendon allograft technique (as opposed to a soft tissue scaffold only) which has the potential to provide immediate bone-tendon integrity and function. As a first step we have evaluated this repair technique using a canine model to assess clinical, imaging, histologic, and biomechanical outcomes compared to allograft tendon alone treatment and control groups at 12 weeks. Overall this study has shown that there was no detrimental effect on canine function and through radiographic and ultrasound images we saw union of the bone-tendon allograft bone-block to native bone and a completely intact bone-tendon junction. These results were confirmed histologically. Biomechanically this novel technique provided a solid repair construct with reasonable stiffness and elongation at the junctions comparable to a known surgical treatment (tendon alone allograft). Further study is underway to evaluate this technique in a larger sample size to longer time points with mobilization protocols applicable to humans. Overall this technique has shown great potential for use in a large, chronic massive tear of the rotator cuff where replacement of the diseased rotator cuff tendon is warranted. (This work is funded by Arthrex and was recently accepted for Podium Presentation at the 55th Annual Orthopaedic Research Society Meeting, Las Vegas, NV).