Assistant Professor Small Animal Orthopedics North Carolina State University, North Carolina
Effect of Epitendinous Suture Augmentation to a Double Krackow Suture Pattern for Canine Gastrocnemius Tendon Repair. Downey A1, Duffy DJ1, Chang Y1, Fisher M1, Moore G2. 1North Carolina State University, Raleigh, NC; 2Purdue University, West Lafayette, IN.
Double Krackow (DK) sutures have recently demonstrated superiority to a three-loop-pulley repair of canine tendons in a prior study. Our objective was to evaluate the effect of a DK suture pattern, with and without epitendinous suture (ES) augmentation in a canine gastrocnemius tendon (GT) model. Transverse tenotomy was performed and repaired with a DK or DK+ES. Yield, peak and failure force, stiffness, occurrence of 1 mm and 3 mm gapping and failure mode were examined. Yield, peak, and failure loads were greater for DK+ES groups. Yield force was 48% greater for DK+ES (149.56 ± 53.26 N) compared to DK (101.27 ± 37.17 N; P = 0.0172). Peak force was 45% greater for DK+ES (P < 0.0001). Failure force was 47% greater for DK+ES (193.752 ± 31.43 N) compared to DK (131.54 ± 22.28 N; P < 0.0001). Construct stiffness was 36% greater for DK+ES (P = 0.04). All (100%) DK and 83% of DK+ES group produced a 1 mm gap with 100% of DK and 33% DK+ES producing a 3 mm gap (P < 0.001). Loads required to create a 3 mm gap were greater for DK+ES (P < 0.013). Suture breakage occurred in 100% of DK which differed from DK+ES, where suture breakage (7/12) and tissue failure (5/12; P = 0.037) predominated. Augmentation of a primary DK repair with an ES significantly improved construct strength while increasing loads required to cause 1 mm and 3 mm gap formation respectively. Limitations include the ex vivo nature and inability to assess the effect of pattern on tendon blood supply. ES augmentation is a simple technique modification that should be recommended to significantly increase tendon repair strength.