Julien Ghelfi1,2, Marylène Bacle3, Olivier Stephanov4, Hélène de Forges2, Ian Soulairol5,6, Pascal Roger7, Gilbert R Ferretti1, Jean-Paul Beregi2, Julien Frandon2. 1. Service de Radiologie Diagnostique et Interventionnelle, CHU Grenoble Alpes, 38043 Grenoble, France. 2. Department of Medical Imaging, Nîmes University Hospital, University of Montpellier, Medical Imaging Group Nîmes, 30000 Nimes, France. 3. Faculty of Medicine, Montpellier Nîmes University, RAM-PTNIM, 30000 Nimes, France. 4. Anatomopathology Department, Grenoble University Hospital, 38043 Grenoble, France. 5. Department of Pharmacy, Nîmes University Hospital, 30000 Nimes, France. 6. ICGM, University of Montpellier, CNRS, ENSCM, 34090 Montpellier, France. 7. Anatomopathology Department, Nimes University Hospital, University of Montpellier, 30000 Nimes, France.
Abstract
BACKGROUND: Therapeutic strategies targeting neovessels responsible for musculoskeletal chronic pain have emerged, including neovessels embolization. Our study aimed to develop a large animal model of patellar tendinopathy with neovascularization. METHODS: Nine 3-month-old male piglets (18 patellar tendons) received percutaneous injections of increasing doses of collagenase (0 to 50 mg) at day 0 (D0). Tendinopathy was evaluated by ultrasound (D7 and D14). Neovascularization was evaluated visually and on angiographies. Bonar score was used for histological analysis (D14). Correlations were evaluated using Spearman's rank (Rs) test. RESULTS: Research protocol was well tolerated. All tendons were enlarged with a median increase of 31.58% [25-40.28] at D7 (p = 0.244) at D7 and 57.52% [48.41-91.45] at D14 (p = 0.065). Tendons with collagenase injection had more hypoechoic changes, with one tendon rupture (p = 0.012). Neovascularization was reported above 5 mg collagenase (p < 0.01) at D7 and D14 with dose-related neovessels induction (Rs = 0.8, p < 0.001). The Bonar score increased above 5 mg collagenase, correlated with the dose (Rs = 0.666, p = 0.003). CONCLUSIONS: The study shows the feasibility, safety and reproducibility of this new large animal model of patellar tendinopathy with neovascularization after collagenase injection. It will allow studying new treatments on direct embolization of neovessels by endovascular approach.
BACKGROUND: Therapeutic strategies targeting neovessels responsible for musculoskeletal chronic pain have emerged, including neovessels embolization. Our study aimed to develop a large animal model of patellar tendinopathy with neovascularization. METHODS: Nine 3-month-old male piglets (18 patellar tendons) received percutaneous injections of increasing doses of collagenase (0 to 50 mg) at day 0 (D0). Tendinopathy was evaluated by ultrasound (D7 and D14). Neovascularization was evaluated visually and on angiographies. Bonar score was used for histological analysis (D14). Correlations were evaluated using Spearman's rank (Rs) test. RESULTS: Research protocol was well tolerated. All tendons were enlarged with a median increase of 31.58% [25-40.28] at D7 (p = 0.244) at D7 and 57.52% [48.41-91.45] at D14 (p = 0.065). Tendons with collagenase injection had more hypoechoic changes, with one tendon rupture (p = 0.012). Neovascularization was reported above 5 mg collagenase (p < 0.01) at D7 and D14 with dose-related neovessels induction (Rs = 0.8, p < 0.001). The Bonar score increased above 5 mg collagenase, correlated with the dose (Rs = 0.666, p = 0.003). CONCLUSIONS: The study shows the feasibility, safety and reproducibility of this new large animal model of patellar tendinopathy with neovascularization after collagenase injection. It will allow studying new treatments on direct embolization of neovessels by endovascular approach.
Authors: Sadaf Ashraf; Helen Wibberley; Paul Ian Mapp; Roger Hill; Deborah Wilson; David Andrew Walsh Journal: Ann Rheum Dis Date: 2010-11-15 Impact factor: 19.103