Question : chez les adultes atteints d’une tendinopathie d’Achille douloureuse de la portion médiane d’une durée supérieure à 3 mois, une seule injection de plasma riche en plaquettes améliore-t-elle la fonction par rapport à une injection simulée 6 mois après le traitement ?

Résultats : cet essai clinique randomisé a inclus 240 participants souffrant de douleur à la partie médiane du tendon d’Achille. Le traitement avec une injection unique de plasma riche en plaquettes intratendineux par rapport à une aiguille sèche sous-cutanée a donné un score moyen d’évaluation d’Achille au Victorian Institute of Sport à 6 mois de 54,4 contre 53,4 (plage de 0 [pires symptômes] à 100 [aucun symptôme]) ; Cette différence n’était pas statistiquement signifiante.

Signification : une seule injection de plasma riche en plaquettes par rapport à une injection simulée n’a pas réduit de manière significative le dysfonctionnement du tendon d’Achille.

Importance  Platelet-rich plasma injections are used as a treatment for chronic midportion Achilles tendinopathy, but evidence for this treatment is limited.

Objective  In adults with midportion Achilles tendinopathy, to assess the effects of a single platelet-rich plasma injection, compared with sham injection, on the outcome of the Victorian Institute of Sport Assessment-Achilles (VISA-A) score (a single composite measure of Achilles tendinopathy severity).

Design, Setting, and Participants  A participant-blinded, multicenter randomized clinical trial that included 240 people from 24 sites assigned to either a platelet-rich plasma injection or a sham injection between April 2016 and February 2020. Final follow-up was July 2020. Participants were older than 18 years with midportion Achilles tendon pain for more than 3 months as confirmed by ultrasound, magnetic resonance imaging, or both.

Interventions  A single intratendinous platelet-rich plasma injection (n = 121) or a single sham injection (insertion of a subcutaneous dry needle not entering the tendon) (n = 119).

Main Outcomes and Measures  The primary outcome was the VISA-A score, measured 6 months after treatment allocation. The VISA-A score contains 8 questions that cover 3 domains of pain, function, and activity, analyzed as a composite score (range, 0 [worst symptoms] to 100 [no symptoms]; minimal clinically important difference in score, 12 points). The primary analysis was adjusted for laterality, age, sex, and baseline VISA-A score.

Results  Among 240 patients assigned to a platelet-rich plasma or sham injection (mean age, 52 years; 138 [58%] women), 221 (92%) completed the trial. At 6-month follow-up, mean VISA-A score values in the plasma-rich plasma group vs the sham injection group were 54.4 vs 53.4 (adjusted mean difference, −2.7 [95% CI, −8.8 to 3.3]). The most common adverse events compared between patients in the platelet-rich plasma group vs the sham group were injection site discomfort (97 vs 73 patients), swelling (56 vs 52 patients) and bruising (48 vs 49 patients).

Conclusions and Relevance  Among patients with chronic midportion Achilles tendinopathy, treatment with a single injection of intratendinous platelet-rich plasma, compared with insertion of a subcutaneous dry needle, did not reduce Achilles tendon dysfunction at 6 months. These findings do not support the use of this treatment for chronic midportion Achilles tendinopathy.

Trial Registration  isrctn.org Identifier: ISRCTN13254422