Limited evidence does not support the use of xenografts to augment the repair of large and massive rotator cuff tears.

One high quality study (Bryant, D. 2016), one moderate quality study (Iannotti, J. 2006), and three low quality studies (Flury, M. 2018 , Walton, J. 2007, Ciampi, P. 2014 ) addressed xenografts as an ancillary surgical technique.  The remainder of published studies either had too few subjects (<20) or involved interposition rather than augmentation of rotator cuff repair.

In a high quality study, Bryant et al. 2016 compared a porcine xenograft patch to no augmentation in the repair of moderate and large size rotator cuff tears.  While they demonstrated non-inferiority for the porcine xenograft, no significant difference was found between the two groups for either re-tear or patient reported outcomes (PROs), although there was a trend to better PROs for the xenografts.

In a moderate quality study, Iannotti et al. 2006 compared a porcine xenograft augmentation in the repair of two tendon tears.  While not statistically significant (p=0.08), the study trended towards worse outcomes in the xenograft augmented group.  Three of 15 developed wound problems in the xenograft group.  The authors did “not recommend using porcine small intestine submucosa to augment repairs of massive chronic rotator cuff tears done with the surgical and postoperative procedures described in this study.”

In a low quality study, Flury et al. 2018 compared the outcome of porcine xenograft augmentation in patients age>60 using a matched-pair comparative trial design.  No difference in outcomes was noted, with a trend (p=0.343) towards more local complications in the xenograft group.  In a different low quality study, Walton et al. 2007 also evaluated a porcine xenograft.  This study noted “no recognizable benefit” with the porcine xenograft, and 4/10 had a severe post-operative reaction requiring further surgical treatment in the xenograft group.  In a low quality cohort study, Ciampi et al. evaluated the results of augmentation with a bovine xenograft augmentation versus no graft in two arms of the study, with a third arm being synthetic patch augmentation.  No difference was noted in strength, elevation, or re-tear rates with xenograft augmentation, compared to no augmentation of the repairs.  No local inflammation was noted in the xenograft group.

Risks and Harms of Implementing this Recommendation
There are no known harms associated with implementing this recommendation.  Multiple other option for augmentation of rotator cuff repairs exist besides xenograft.

Future Research
While the evidence available to recommend for or against xenograft augmentation is mixed, the absence of clear benefit associated with these grafts, and the increased incidence of post-operative reaction coupled with the absence of reports of these reactions with allograft augment would seem to indicate that further research is not warranted at this time on xenografts in their current form.


The Future of OrthoGuidelines


The OrthoGuidelines Process