Summary

Integration of Human Dermal Allograft with repaired native rotator cuff to improve functional outcome

Abstract

Background

Despite the advancements in rotator cuff repair techniques, re-tear rate is still a concern with re-tear rates of between 15-21%. The aim of using patch augments in rotator cuff repair is to induce native tissue growth, providing biomechanical support and an optimal environment for rotator cuff healing. The use of dermal allograft to augment rotator cuff repair has been reported to improve clinical outcome. However, there have been no study looking into integration of the dermal allograft with the repaired rotator cuff on magnetic resonance imaging.

Methods

To evaluate potential of dermal allograft integration with native repaired rotator cuff, re-tear rate, clinical outcome scores and range of motion pre- and post-operatively and to compare the outcomes between arthroscopic group and open groups. Proposed Rhee Classification for repaired rotator cuff-graft integration based on MRI images, four grades, Grade I: healing complete, Grade II: Graft-native repaired rotator cuff healing evolving, Grade III: graft above rotator cuff, not integrated yet, Grade IV: graft loosening with re-tear

Results

Total patients: 92; Arthroscopic: 78, Open: 14; Number of patients with follow up MRI: 37. Mean follow up: 15 months. 65% of patients show integration of graft at an average time of 8 months. Re-tear rates of 7.6%. Significant increment in AHI from 7.99 (pre op) to 8.88 (post op), p .002. Improvement in FF 150-162 (p .002), abduction 84-88 (p .051), internal rotation 40-46 (p .105) and external rotation 54-67 (p .0004). Improvement in Visual analogue score from 5.3 (pre op) to 1.6 (post op). All parameter comparing arthroscopic vs open groups were statistically insignificant.

Conclusion

65% of our patients showed graft integration on MRI at an average time of 8 months. At post op clinic follow up, physical examination of shoulder revealed smooth gliding of the humeral head underneath the acromion with no defects or clicks felt on palpation. We believe that these findings and the increased AHI postoperatively contributes to improvement in VAS and functional scores. The re-tear rate in our series was 7.6%, which was a lot better than re-tear rates of other repair techniques documented in literature. Furthermore, there were no differences in final outcomes seen comparing the arthroscopic and open groups. Surgeons should not hesitate to convert to an open repair if indicated.
In summary, dermal allograft integration with native repaired rotator cuff can be expected to be seen on MRI. This technique offers improved clinical outcome and reduces re-tear rates.