Another blood spinning study finds no improvement in Achilles tendons


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Actually, the title isn’t quite true — this is a just new wrinkle on the same Dutch study reported earlier this year that found no difference between platelet-rich plasma injections and placebo (saline) injections for 54 patients with chronic Achilles tendinopathy. The new paper, just published online at the British Journal of Sports Medicine, presents further data from this experiment: in addition to the previously reported pain scores (which, admittedly, are a bit wishy-washy and subjective), they used “ultrasonographic tissue characterization, a novel technique which quantifies tendon structure.”

Basically, they used ultrasonic imaging combined with computer image recognition to get an automatic (i.e. objective) measure of tendon health. The results: scores improved for both PRP and placebo (note that the subjects were also doing a rehab regime involving eccentric exercises during the study), but there was no significant difference between the groups.

Given the results presented earlier, this isn’t a big surprise — and of course, certainly isn’t proof that PRP doesn’t work in any context. But it’s another reason for skepticism. As the authors conclude, “these data argue against clinical use of this form of PRP in present clinical practice.”

5 Replies to “Another blood spinning study finds no improvement in Achilles tendons”

  1. A new “wrinkle”, as opposed to a new “spin”? Your discipline to refrain from using such an obvious, gratuitous pun is most impressive!

  2. No mention of blinding. Ultrasonography isn’t a straightforward technique. There is a great deal of interoperator variability, which could be affected if the operator knew the treatment arms of the subjects. Even if this study was positive, it’d still be subject to major criticism.

  3. @thedocsquawk
    Actually, if you click on the link to the abstract of the paper, it notes that this was a “double-blind, randomized, placebo-controlled clinical trial.”

    As for the interoperator variability, they addressed this by using a computer algorithm to assess the data. Here’s a passage from the paper:

    “Conventional ultrasonography is frequently used to image tendon disorders. Ultrasonography is an operator-dependent technique, and transducer handling and machine settings can influence the image obtained. Consequently, the interobserver reliability of ultrasonographic assessment of tendon structure is not known, and changes in time may be difficult to compare. In veterinary medicine, a method for computerised ultrasonographic tissue characterisation (UTC; UTC imaging, Stein, The Netherlands) has been developed,in which ultrastructural organisation of tendon tissue could be matched with histomorphology of equine tendons as a reference test. Recently, this novel technique was found to be a reliable method, which was able to distinguish symptomatic from asymptomatic human Achilles tendons by quantifying the three-dimensional stability of the echopattern over contiguous images.”

    Regardless, it was a double-blinded trial with all assessments performed by the same researcher, so interoperator variability isn’t really an issue.

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