AN IN-VITRO BIOMECHANICAL INVESTIGATION OF COMPRESSION PLATING WITH CABLE CERCLAGE FOR REPAIR OF OBLIQUE OSTEOTOMIES IN FOAL FEMURS

Long oblique diaphyseal osteotomies were created in 14 pairs of femurs from cadaver foals less than sis months of age. One bone from each pa ir was repaired using two dynamic compression plates (DP), and the oth er was repaired using a dynamic compression plate with cable cerclage (CC). Seven pairs were tested in compression and seven pairs in cranio lateral-caudomedial (CrL-CdM) three-point bending. A difference was no t found in mean (+/- SD) breaking strength in compression between the DP (7257.19 +/- 2004.08 N) and CC (7761.41 +/- 2552.91 N) techniques. Nor was there a difference in mean stiffness in compression between th e DP (2533.83 +/- 1777.38 N/mm) and CC (3177.98 +/- 1694.70 N/mm) tech niques. There was no difference in mean stiffness in three-point bendi ng between the DP (244.60 +/- 60.80 N/mm) and CC (195.50 +/- 80.90 N/m m) techniques. The mean bending breaking strength and bending moment f or the DP technique (2839.36 +/- 199.46 N and 124,932,00 +/- 8776.38 N mm) was significantly (P = 0.02) greater than the CC technique (1940. 39 +/- 732.80 N and 85,377.72 +/- 32243.34 N mm). The CC system was in ferior to the DP technique in CrL-CdM three-point bending strength and moment, but provided equal bending stiffness and equal compressive st rength and stiffness.