The Value of Platelet-Rich Plasma in Chronic Midportion Achilles Tendinopathy: a Double-blind Randomized Clinical Trial
Condition: Achilles Tendinopathy
MeSH terms: Tendinopathy
Study type: Interventional
Phase: Phase 4

Summary: 
      The study will be a double-blind randomized single-center clinical trial comparing 3
      treatment groups with chronic midportion Achilles tendinopathy.
    

Detailed description: 
      Introduction- Overuse injury of the Achilles tendon is a common entity in athletes and older
      athletes are at an increased risk. When the exact origin of tendon pain is unclear, the term
      tendinopathy is preferred. Most accepted treatment at this moment is an eccentric exercise
      programme, according to the Dutch guidelines. However, a recent systematic review on the
      effectiveness of eccentric exercises to treat lower extremity tendinoses concluded that it is
      unclear whether eccentric exercises are more effective than other forms of treatment.

      Recent studies described new treatment strategies in tendinopathies, such as the use of
      platelet-rich plasma (PRP). Platelets can participate actively in tissue repair processes and
      stimulate the release of several growth factors. Recently, it was found that platelet-rich
      plasma clot releasate stimulates cell proliferation, collagen deposition, and enhances the
      gene expression of matrix degrading enzymes and endogenous growth factors by human tendon
      cells in vitro. The only published clinical cohort study in tendon research reported 93%
      reduction of pain for PRP-treated patients with chronic elbow tendinosis. Also on short term
      follow-up, the PRP injection was more beneficial than injection with an anaesthetic agent.

      Aim- To monitor the potential clinical improvement of chronic midportion Achilles
      tendinopathy after injection with PRP and to evaluate the recovery process in time using a
      new Ultrasonographic method (Ultrasonographic Tissue Characterisation).

      Hypothesis: The average VISA-A score is higher in the patient group treated with eccentric
      exercise therapy in combination with a PRP injection in comparison with the group treated
      with a saline injection in combination with eccentric exercises.

      Study population- In total, 54 patients with symptomatic Achilles tendinopathy will be
      included in the study.

      Study design- The study will be a double-blind randomised single-centre clinical trial
      comparing 2 treatment groups. The researcher, the sports medicine physician and the patients
      will be blinded to the received therapy.

      Therapy- All patients will perform a heavy load eccentric exercise programme, consisting of
      180 repetitions daily. The patients will be randomised into 2 treatment groups: ultrasound
      guided intratendinous saline injection with eccentric exercises and ultrasound guided
      intratendinous PRP injection with eccentric exercises.

      Follow-up- Follow-up (clinically and ultrasonographically) will be at 6, 12, 24 and 52 weeks.
      At 24 weeks, the researcher will be unblinded after the analysis of the preliminary data. The
      patients will remain blinded to the therapy until 52 weeks follow-up. At 52 weeks follow-up a
      second, blinded researcher will evaluate the patients using the primary and secondary outcome
      measurements.

      Outcome measurements- Primary outcome measurement: VISA-A score, a validated instrument to
      detect the severity of symptoms in patients with Achilles tendinopathy. As secondary outcome
      measurements subjective patient satisfaction and return to sports will be rated. For the
      evaluation of tendon repair, Ultrasonographic Tissue Characterization (UTC) and Power Doppler
      ultrasound (PDU) will be performed. UTC was previously developed in horse tendons and
      provides quantitative information on tendon fiber alignment and the related ultra-structural
      integrity of the tendon tissue through a non-invasive approach.
    

Intervention name(s): PRP Injection with eccentric exercises; Placebo Injection with eccentric exercises
Intervention type(s): Biological; Biological
Intervention description(s): PRP Injection with eccentric exercises; Placebo Injection with eccentric exercises
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment