Biological Augmentation with Platelet Derived Products
Strong evidence does not support biological augmentation of rotator cuff repair with platelet-derived products on improving patient reported outcomes; however, limited evidence supports the use of liquid platelet rich plasma (PRP) in the context of decreasing re-tear rates.

Rationale

Several high strength studies confirm that the addition of liquid platelet-rich plasma or platelet-rich fibrin does not significantly change patient-reported outcomes.

Seven high quality studies (Jo, C.H. 2015; Malavolta, E.A. 2014; Pandey, V. 2016; Randelli, P., 2011; Wang, A. 2015; Zhang, Z. 2016; Flury 2016)  that investigated the effect of liquid platelet rich plasma (PRP) on post-operative full thickness re-tear rates.  A pooled analysis of randomized trials demonstrated a lower relative risk of full thickness re-tear [RR=0.43 (95% CI 0.26 – 0.69)] when patients treated PRP were compared with controls.  While there was minimal statistical heterogeneity (I2=3.6%) in this analysis, there was a significant amount of clinical variability in the size of the tears, the type of PRP kit that was utilized, PRP application techniques, and fixation constructs.  Given that an uncontrolled analysis was conducted (i.e. not enough studies for a meta-regression), the results should be interpreted with caution.  With respect to platelet rich fibrin, there is insufficient evidence to make a recommendation for or against its utilization in reducing post-operative rotator cuff re-tear rates. Due to limited numbers in the pooled analysis, subgroup analyses for rotator cuff tear size could not be performed.

Risks and Harms of Implementing this Recommendation
There are no known harms associated with the use of PRP.

Future Research
Future studies should standardize the type of PRP formulation utilized or at the very least measure the concentrations of key constituents.  Furthermore, larger studies will allow for controlled statistical analyses that consider the effect of confounders such as fixation constructs, marrow venting, size of tears, etc. Consistency in the definition of rotator cuff re-tear is also encouraged.