Platelet-Rich Plasma Injection for Chronic Achilles Tendinopathy

Purpose of the study: To examine whether a PRP injection would improve outcome in chronic midportion Achilles tendinopathy.

The Study: A stratified, block-randomized, double-blind, placebocontrolled trial at a single center (The Hague Medical Center, Leidschendam, the Netherlands) of 54 randomized patients aged 18 to 70 years with chronic tendinopathy 2 to 7 cm above the Achilles tendon insertion. The trial was conducted between August 28, 2008, and January 29, 2009, with follow-up until July 16, 2009. Eccentric exercises (usual care) with either a PRP injection (PRP group) or saline injection (placebo group). Randomization was stratified by activity level.

Results: although both groups improved from baseline there was no difference statistically or clinically between the two groups. Reviewing the 95% confidence intervals about the primary outcome a clinically important difference was not missed.

Study strengths:

• the trial was registered clinicaltrials.gov Identifier: NCT00761423

• the authors provided a detailed description of the randomization process

• an understandable description of concealment allocation process was provided

• the randomization process was stratified for pre-injury  level thought to be a confounder for the primary outcome

• clear description of the blinding process was described

• the data was evaluated on intention to treat basis; there was no lost to follow-up

• the primary outcome measure was a validated patient oriented instrument

• a power calculation was described with a clinically important difference specified

• both groups appear to be equal at baseline

• the results of the primary outcome reported as a point estimates with 95% confidence intervals

Study weaknesses:

None

Comments:

A well-planned and reported clinical trial which should provide important information to practicing podiatrist utilizing platelet-rich plasma injections for foot pathology. The authors provide a clear description of the subjects and the intervention which allows for podiatric physicians to determine the relevancy to their practices.

1/2010