Table II.
Platelet rich plasma (PRP) compared with control intervention for tendinopathies: summary of findings§.
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | N. of participants (studies) | Quality of evidence (GRADE) | Comments | |
|---|---|---|---|---|---|---|
| Assumed risk | Corresponding risk | |||||
| Control | PRP | |||||
| PAIN score: Visual Analogue Score (VAS) | Various controls, including local steroids injection | VAS 0–100 (higher scores = worse pain) | ||||
| VAS - short-term follow-up (1–3 months) - Elbow tendinopathy |
Mean VAS score across control groups ranged from 17 to 45.5 in control groups | Mean VAS score in the intervention groups was 2.86 lower (8.57 lower to 2.85 higher) | MD −2.86 (95% CI: −8.57 to 2.85) | 6 studies (328 participants) | ⊕⊖⊖⊖ very low1, 2, 3 |
On average, it is unclear whether or not use of PRP compared to controls reduces pain score at short-term follow up. The between group differences were small and unlikely to be clinically important |
| VAS - medium-term follow up (4–6 months). - Elbow tendinopathy |
Mean VAS score across control groups ranged from 25 to 55.8 in control groups | Mean VAS score in the intervention groups was 12.97 lower (5.34 to 20.61 lower) | MD −12.97 (95% CI: −20.61 to −5.34) | 3 studies (158 participants) | ⊕⊖⊖⊖ very low1,2 |
Marginal clinical benefit of PRP at medium-term follow up. The between group differences were small and unlikely to be clinically important |
| VAS - short-term follow up (1–3 months) - Plantar fasciitis |
Mean VAS score ranged across control groups from 5 to 65 in controls groups | Mean VAS score in the intervention groups was 2.86 lower (8.57 lower to 2.85 higher) | MD −2.86 (95% CI: −8.57 to 2.85) | 8 studies (420 participants) | ⊕⊖⊖⊖ very low 1,2, 3 |
On average, it is unclear whether or not use of PRP compared to controls reduces pain score at short-term follow up. The between group differences were small and unlikely to be clinically important |
| VAS - medium-term follow up (4–6 months) -Plantar fasciitis |
Mean VAS score across control groups ranged from 5 to 48 in controls groups | Mean VAS score in the intervention groups was 7.87 lower (14.9 lower to 0.85 lower) | MD −7.87 (95% CI: −14.9 to −0.85) | 6 studies (300 participants) | ⊕⊖⊖⊖ very low1, 2 |
Marginal clinical benefit of PRP at medium-term follow up. The between group differences were small and unlikely to be clinically important |
| Serious adverse events (0–6 months) - Elbow tendinopathy, plantar fasciitis, Achilles tendinopathy, rotator cuff tendinopathy |
0 events | 0 events | Not estimable | 22 studies (1,265 participants) | ⊕⊖⊖⊖ very low1, 2, 3 |
There were no reports of serious adverse events (e.g. injection site infection, plantar fascia rupture) during the follow-up period (1.5–24 months) of 22 trials |
| Function score: American Orthopedic Foot and Ankle Society Score (AOFAS) | Controls were represented only by local steroids injection | AOFAS 0–100 (higher score=better function) | ||||
| AOFAS - short-term follow up (1–3 months) - Plantar fasciitis |
Mean AOFAS score across control groups ranged from 81 to 96.8 in control groups (steroids) | Mean AOFAS score in the steroids groups was 4.26 higher (3.96 lower to 12.47 higher) than in intervention group | MD 4.26 (95% CI: −3.96 to 12.47) | 4 studies (188 participants) | ⊕⊖⊖⊖ very low1, 2, 3 |
On average, it seems that the use of PRP compared to local steroids injection does not increase function score at short-term follow-up |
| AOFAS - medium-term follow up (4–6 months) - Plantar fasciitis |
Mean VAS score across control groups ranged from 74 to 97.2 in controls groups (steroids) | Mean AOFAS score in the steroids groups was 4.25 higher (5.92 lower to 14.42 higher) than in intervention group | MD 4.25 (95% CI: −5.92 to 14.42) | 5 studies (218 participants) | ⊕⊖⊖⊖ very low1,2, 3 |
On average, it seems that the use of PRP compared to local steroids injection does not increase function score at medium-term follow-up |
Patient/population: adults with elbow tendinopathy or plantar fasciitis; Settings: outpatient; Intervention: PRP; Comparison: various controls, including local steroids injection, placebo, autologous whole blood, anaesthetic.
The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95%CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95%CI). GRADE: Working Group grades of evidence. High quality: further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: we are very uncertain about the estimate.
Down-graded once for inconsistency, due to substantial heterogeneity (I2>80%).
Down-graded twice because of high risk of bias or unclear risk of selection bias, and at high risk of other bias (unbalance at baseline between groups) in several of the selected studies.
Down-graded once for imprecision (95%CI includes line of no effect).
Down-graded once due to serious risk of bias (especially reporting bias) and twice for very serious imprecision (no events). CI: confidence interval; MD: mean difference.