Autologous bone marrow expanded mesenchymal stem cells in patellar tendinopathy: protocol for a phase I/II, single-centre, randomized with active control PRP, double-blinded clinical trial

J Orthop Surg Res. 2019 Dec 16;14(1):441. doi: 10.1186/s13018-019-1477-2.


Introduction: Patellar tendon overuse injuries are common in athletes. Imaging may show a change in tissue structure with tendon thickening and disruption of the intratendinous substance. We wish to test the hypothesis that both autologous bone marrow expanded mesenchymal stem cells and autologous leukocyte-poor platelet-rich plasma (LP-PRP) implanted into the area of the disrupted tendinopathic patellar tendon will restore function, but tendon regeneration tissue will only be observed in the subjects treated with autologous bone marrow expanded mesenchymal stem cells.

Methods and analysis: This is a single-centre, pilot phase I/II, double-blinded clinical trial with randomisation with active control. Twenty patients with a diagnosis of patellar tendinopathy with imaging changes (tendon thickening and disruption of the intratendinous substance at the proximal portion of the patellar tendon) will be randomised in a 1:1 ratio to receive a local injection of either bone-marrow autologous mesenchymal stem cells (MSC), isolated and cultured under GMP at The Institute of Biology and Molecular Genetics (IBGM) (Spain) or P-PRP. The study will have two aims: first, to ascertain whether a clinically relevant improvement after 3, 6 and 12 months according to the visual analogue scale (VAS), Victorian Institute of Sport Assessment for patellar tendons (VISA-P) and dynamometry scales (DYN) will be achieved; and second, to ascertain whether the proposed intervention will restore tendon structure as determined by ultrasonography (US), Doppler ultrasonography (DUS), and innovative MRI and ultrasound techniques: Magnetic Resonance T2 FAT SAT (UTE, Ultrashort Echo TE) sequence and Ultrasound Tissue Characterization (UTC). Patients who are randomised to the P-PRP treatment group but do not achieve a satisfactory primary endpoint after 6 months will be offered treatment with MSC.

Trial registration: NCT03454737.

Keywords: Tendinopathy; Mesenchymal stem cells; Platelet-rich plasma.

Publication types

  • Clinical Trial Protocol

MeSH terms

  • Adolescent
  • Adult
  • Clinical Trials, Phase I as Topic / methods
  • Clinical Trials, Phase II as Topic / methods
  • Double-Blind Method
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Mesenchymal Stem Cell Transplantation / adverse effects
  • Mesenchymal Stem Cell Transplantation / methods*
  • Mesenchymal Stem Cells / cytology*
  • Middle Aged
  • Pain Measurement / methods
  • Patellar Ligament* / diagnostic imaging
  • Patient Selection
  • Pilot Projects
  • Randomized Controlled Trials as Topic / methods
  • Research Design
  • Tendinopathy / diagnostic imaging
  • Tendinopathy / therapy*
  • Treatment Outcome
  • Ultrasonography
  • Young Adult

Associated data