Basic Orthopedic Science

Basic orthopedic research at St. Michael’s Hospital is conducted in the joint laboratory of Drs. Aaron Nauth and Emil Schemitsch. Housed at the Keenan Research Centre for Biomedical Science, the musculoskeletal research laboratory has access to a state of the art bioimaging facility, plus numerous molecular biology and histology resources.


About the Lab

With the wealth of available equipment, resources and techniques, the lab focuses on musculoskeletal injury and repair, as well as the use of stem cell therapies as they apply to orthopaedics. Current research is focused on developing strategies to improve healing in complex fractures and rotator cuff injuries.

H & E stained health rotator cuff slide

H & E stained health rotator cuff slide

In the laboratory, bone marrow derived stem cells is collected, cultured, characterized and placed into animal models to observe their effects on bone and soft tissue healing. Assessments typically include X-ray and micro-computed tomography (micro-CT scanning), histology, gene analysis and biomechanical testing. Initial results indicate these cells can have a significant improvement on bone and blood vessel formation in fracture models, and improved tendon strength in rotator cuff injuries. Continued testing and optimization of these novel techniques will hopefully translate to clinical trials and improved orthopedic patient outcomes.

Fluorescently labeled stem cells

Fluorescently labeled stem cells

Featured Publications

  • Subtypes of endothelial progenitor cells affect healing of segmental bone defects differently.Giles EM, Godbout C, Chi W, Glick MA, Lin T, Li R, Schemitsch EH, Nauth A. Int Orthop. 2017 Nov;41(11):2337-2343.
  •  Delayed Endothelial Progenitor Cell Therapy Promotes Bone Defect Repair in a Clinically Relevant Rat Model. Bates BD, Godbout C, Ramnaraign DJ, Schemitsch EH, Nauth A.Stem Cells Int. 2017;2017
  • BMP-2 mRNA expression after endothelial progenitor cell therapy for fracture healing. Li R, Nauth A, Gandhi R, Syed K, Schemitsch EH. J Orthop Trauma. 2014 Apr;28 Suppl 1:S24-7.
  • Expression of VEGF gene isoforms in a rat segmental bone defect model treated with EPCs. Li R, Nauth A, Li C, Qamirani E, Atesok K, Schemitsch EH. J Orthop Trauma. 2012 Dec;26(12):689-92.
  • Endothelial progenitor cells: a novel cell-based therapy in orthopaedic surgery. Atesok K, Li R, Schemitsch E. J Am Acad Orthop Surg. 2012 Oct;20(10):672-4
  • An emerging cell-based strategy in orthopaedics: endothelial progenitor cells. Atesok K, Matsumoto T, Karlsson J, Asahara T, Atala A, Doral MN, Verdonk R, Li R, Schemitsch E. Knee Surg Sports Traumatol Arthrosc. 2012 Jul;20(7):1366-77
  • Stem cells for the repair and regeneration of bone. Nauth A, Schemitsch EH. Indian J Orthop. 2012 Jan;46(1):19-21
  • Endothelial progenitor cells for fracture healing: a microcomputed tomography and biomechanical analysis. Li R, Atesok K, Nauth A, Wright D, Qamirani E, Whyne CM, Schemitsch EH. J Orthop Trauma. 2011 Aug;25(8):467-71
  • Effect of human vascular endothelial growth factor gene transfer on endogenous vascular endothelial growth factor mRNA expression in a rat fibroblast and osteoblast culture model. Li R, Li CH, Nauth A, McKee MD, Schemitsch EH. J Orthop Trauma. 2010 Sep;24(9):547-51
  • Endothelial progenitor cells promote fracture healing in a segmental bone defect model. Atesok K, Li R, Stewart DJ, Schemitsch EH. J Orthop Res. 2010 Aug;28(8):1007-14