Platelet-Rich Plasma for Patellar Tendinopathy: A Randomized Controlled Trial of Leukocyte-Rich PRP or Leukocyte-Poor PRP Versus Saline
Scott A · The American Journal of Sports Medicine (2019)
DOI: 10.1177/0363546519837954The Scott/LaPrade multicenter RCT tested LR-PRP versus saline in 57 patients with chronic patellar tendinopathy lasting more than 6 months. The primary outcome was VISA-P score at 12 weeks, with follow-up to 6 months. The study found no significant difference between groups, with approximately 58% of patients improving regardless of treatment allocation, suggesting a strong natural history or placebo response in chronic patellar tendinopathy.
Clinical Relevance
Tempers enthusiasm for PRP in chronic patellar tendinopathy. Clinicians should be cautious about recommending PRP for this condition given the high natural improvement rate. The choice of LR-PRP (rather than LP-PRP) may have influenced results.
Key Takeaways
- No significant PRP benefit over saline for chronic patellar tendinopathy
- 58% improved in both groups, indicating strong natural history/placebo effect
- Used LR-PRP, which may not be the optimal formulation for this condition
- Chronic disease duration (>6 months) may represent a population less responsive to PRP
- Highlights that not all tendinopathies respond equally to PRP
Key Findings
At 12 weeks, 58% of all participants improved regardless of group. No statistically significant difference among LR-PRP (35%), LP-PRP (72%), and saline (71%).
Clinical Context
Study Design
Randomized Controlled Trial (Multicenter)
Condition
Chronic Patellar Tendinopathy
Sample Size
57 patients
Follow-up
3 months
Control Group
Saline
Primary Outcome
VISA-P
PRP Protocol & Intervention
Leukocyte Status
LR-PRP and LP-PRP
Injection Frequency
1 injection(s)
Guidance Method
Ultrasound