The PATH-2 trial found no evidence of a benefit of Platelet Rich Plasma (PRP) injection versus a placebo after Achilles tendon rupture (ATR) at six-months. ATR often leave longer-term functional deficiencies beyond six-months. This study aim is to determine if PRP affect tendon functional outcomes at two-years after rupture. Randomised multi-centre two-arm parallel-group, participant- and assessor-blinded, superiority trial.Background
Study design
Disability and slow return to sport and work after tendon rupture are major challenges. Platelet Rich Plasma (PRP) is an autologous supraphysiological concentration of platelets from whole blood that has demonstrated positive cellular and physiological effects on healing in laboratory conditions but evidence from adequately powered robust clinical trials is lacking. We aimed to determine the clinical efficacy of PRP for treatment of acute Achilles tendon rupture. In a placebo-controlled, participant- and assessor-blinded, trial at 19 NHS hospitals we randomly assigned 230 adults starting acute Achilles rupture non-surgical management to PRP injection or dry-needle insertion (placebo) to the rupture gap under local anaesthetic. Patients with confounding or contraindicated concurrent medical conditions were excluded. The primary outcome was muscle-tendon function, assessed by the limb symmetry index (LSI, uninjured limb/injured limb × 100, higher scores better) of the work (Joules) performed during the heel-rise endurance test at 24 weeks. Secondary outcomes were: Achilles Tendon Rupture Score (ATRS, 0–100, higher scores better), quality of life (SF-12), pain, and goal attainment. Trial registration: ISRCTN54992179Background
Methods
We previously reported that disruption of TGFβ signaling in limb mesenchyme resulted in complete failure of tendon differentiation. To bypass this early function and study additional roles of TGFβ signaling in tendon development we disrupted TGFβ signaling in tenocytes after they assumed the tendon cell fate by using the tendon deletor ScxCre to target the floxed type2 TGFβ receptor.Introduction
Materials and Methods