The effect of platelet concentrates on graft maturation and graft-bone interface healing in anterior cruciate ligament reconstruction in human patients: a systematic review of controlled trials.

PURPOSE To systematically review the current evidence for the effects of platelet concentrates on (1) graft maturation and (2) graft-bone interface healing in anterior cruciate ligament (ACL) reconstruction in human, controlled trials and for ensuing differences in clinical outcomes. METHODS A systematic search of PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Embase, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews was performed for controlled trials of human ACL reconstruction with and without platelet concentrates. Data validity was assessed, and data were collected on graft maturation, graft-bone interface healing, and clinical outcome. RESULTS Eight studies met the inclusion criteria. Seven studies reported on graft maturation with significantly better outcomes in the platelet groups in 4, and there were large differences in means in an additional 2 studies. Five studies reported on tunnel healing, and 4 found no difference between groups. Three studies assessed clinical outcome but found no differences, regardless of whether they had shown a beneficial effect (1 of 3) or no effect (2 of 3) of platelets on graft and tunnel healing. CONCLUSIONS The current best evidence suggests that the addition of platelet concentrates to ACL reconstruction may have a beneficial effect on graft maturation and could improve it by 20% to 30% on average, but with substantial variability. The most likely mode of action is that treatment with platelets accelerates graft repopulation and remodeling, and this interpretation is supported by the existing data and is biologically plausible. However, the current evidence also shows only a very limited influence of platelet concentrates on graft-bone interface healing and no significant difference in clinical outcomes. LEVEL OF EVIDENCE Level III, systematic review of Level I, II, and III studies.