Efficacy and Regulation of Platelet-Rich Plasma in ACL Reconstruction

Platelet-rich plasma (PRP) added to anterior cruciate ligament reconstruction is examined in a systematic review and meta-analysis pooling randomized trials; it shows short‑term postoperative benefits but no durable functional gains through two years. The main clinical implication: PRP’s value appears concentrated in early rehabilitation rather than in lasting pain or function improvement.

Across 12 randomized controlled trials with follow-up to two years, pooled outcomes included pain scores, KT-1000 knee laxity, and standard functional scales, reported as standardized mean differences with time stratification. The pooled data show consistent short‑term pain reduction at six months and improved mechanical stability on KT‑1000 testing (validation_confidence 0.95), supporting interval‑limited effects rather than durable restoration.

Specifically, PRP produced a significant reduction in pain at six months (standardized mean difference ≈ -0.36, 95% CI -0.62 to -0.10, P = 0.006) and a meaningful improvement in KT-1000 arthrometer measurements (SMD ≈ -0.51, 95% CI -0.82 to -0.19, P = 0.001), although no significant differences were observed at 12 or 24 months; these pooled observations derive from 12 randomized controlled trials that together enrolled approximately 599 patients.

Pooled function scores (IKDC, Lysholm, Tegner) did not show significant between-group gains at the assessed intervals, indicating that the direction and magnitude of benefit are interval-dependent and statistically confined to early follow-up.

Safety reporting in the included trials was limited: no consistent signal of increased adverse events emerged, yet sparse adverse-event data precluded a formal pooled safety estimate. Substantial heterogeneity in PRP preparation and application — including platelet concentration, leukocyte content, activation method, volume, timing of delivery, and graft-augmentation technique — limits reproducibility and complicates interpretation of treatment effects.

The combination of limited safety data and procedural variability underscores the need for standardized preparation protocols and clearer regulatory frameworks to support reproducible clinical application.

Looking forward, this evidence aligns short-term therapeutic effects with priorities for protocol standardization and further randomized trials rather than with expectations of lasting functional recovery.

Key Takeaways:

• PRP demonstrates short-term analgesic effects at six months and improves KT-1000–measured knee stability but does not provide sustained pain or functional benefits through two years.
• Evidence derives from 12 randomized trials with pooled effect estimates supporting interval-dependent benefits (validation_confidence 0.95).
• Safety reporting was limited and PRP preparation variability is a major limitation, underscoring the need for standardized protocols and clearer regulation.