Development of a Murine Model of Pyogenic Flexor Tenosynovitis

ABSTRACT Background To demonstrate the plausibility of a murine model of pyogenic flexor tenosynovitis. Methods 2μL of sterile PBS or bioluminescent Xen29 Staphylococcus aureus was administered to the tendon sheath of 36 male C57BL/6J mice. The infectious course was monitored by bioluminescence (BLI) signal via IVIS imaging and recording of weight change. The infected hind paws were harvested at four time points: 24 hours, 72 hours, 1 week and 2 weeks for histopathology using Alcian Blue hematoxylin staining. Two-way ANOVA with Sidak’s multiple comparison test was used for statistical analysis. Results The infected cohort displayed significantly elevated bioluminescent values, reductions in weight, and exhibited swelling of the infected digit throughout the course of infection. By day 7 most infected mice saw a substantial decrease in BLI signal intensity, however two infected mice exhibited persistent BLI intensity through day 14. Histopathology of the infected cohort showed tissue disorganization and the presence of a cellular infiltrate in and around the flexor tendon sheath. Conclusions A murine model of pyogenic flexor tenosynovitis is possible. Further optimization of the model offers an experimental platform for investigation of the pathophysiology of pyogenic flexor tenosynovitis. Clinical Relevance This animal model can be utilized in order to elucidate the basic molecular/cellular mechanisms of pyogenic flexor tenosynovitis while simultaneously evaluating novel therapeutic strategies.