Kelley M. Thieman, DVM 1 , Antonio Pozzi, DMV, MS, Diplomate ACVS 1 , Hang-Yin Ling, PhD 1 , and Dan Lewis, DVM, Diplomate ACVS 1 1 Comparative Orthopaedics Biomechanics Laboratory, University of Florida, Gainesville, FL Veterinary Surgery April 2010 39 3 355-362 ABSTRACT Objective: To evaluate the biomechanical effect of horizontal, vertical, and cruciate suture repairs and partial meniscectomy on contact mechanics of dog stifles. Study Design: Ex vivo experimental study. Sample Population: Cadaveric canine stifles (n=24). Methods: Simulated bucket handle medial meniscal tears were created in cadaveric dog stifles. Tears were treated with 1 of 3 suture repair techniques or partial meniscectomy. Instantaneous contact area (CA), mean contact pressure (MCP), and peak contact pressure (PCP) measurements were recorded with a pressure sensing system. CA, MCP, and PCP for intact stifles (control), stifles with simulated tears, and stifles after treatment were recorded and compared using 1-way repeated measures ANOVA. Results: Stifles with bucket handle tears had significantly decreased CA, increased MCP and increased PCP when compared with control. All meniscal repair techniques reestablished normal contact mechanics. When comparing meniscal repair and partial meniscectomy, stifles with partial meniscectomy had ∼35% lower CA, 57% higher MCP, and 55% higher PCP than stifles undergoing repair. Conclusions: Contact mechanics obtained from each repair technique were mechanically superior to partial meniscectomy. Performing meniscal repair instead of partial meniscectomy in dogs with select meniscal tears may mitigate the development of degenerative joint disease. Criteria for selection of candidates for meniscal repair should be confirmed with future studies. Clinical Relevance: Based on this ex-vivo model, meniscal repair will restore normal contact mechanics. Consideration should be given to meniscal repair as treatment for peripheral meniscal tears located in the vascular zone if the meniscal parenchyma is normal.