Surgery - Implants Polished implants - thick fibrous capsule that does not adhere to implants : Textured implants - fibrous cells adhere tightly to implants
Surgery - Implants Microtexture promotes cellular attachment Burnett DM. Exp Cell Research 164:1986 Once tissue attachment achieved, bacterial progression retarded Myojin K. Biomed Metal Research 12:1978
Surgery - Implants Polished dense material resist acute bacterial infections Polished material required 40x greater bacterial load to establish infection vs. porous implant Cordero J et al. JBJS 76Br:717,1994 Merritt K. J Biomed Material Research 13:101,1979
Implants “the race for the surface” Gristina AG. Science 237:1588,1987 Tissue integration Implant Colonize ? infection
Surgery - Implants Colonization - Moussa FW Am. Journal Ortho 26:617,1997 Elective implant removal cultures - 10% positive in 21 pts Colonization can occur without sepsis
Surgery - Implants Melcher Ga et al. Injury 27:SC3-26, 1996 In an inoculated infection model in rabbits Titanium implants lower infection rate than ss Solid IMN lower infection rate than cannulated Reaming increased infection rates Implants may matter ? Statistically significant, clinically insignificant
Surgery - Stable Implants Merritt K & Dowd JD. J Ortho Res 5:23,1987 Contaminated rodent osteotomy Infection rate –Unstabilized (71%) –Stabilized - IMN (38%) Worlock P. et al. Injury 25:31,1994 Fracture - plate infection - 71% Fracture - IMN infection - 35%
Surgery - Implants Summary In a contaminated wound, implants that are: –polished –solid –titanium –unreamed may be advantageous in preventing infection