An animal model for open femur fracture and osteomyelitis: Part I.
Infection is an everyday problem in orthopaedics and is quite common in open fracture management. To study this process and provide a basis to prevent infection, we developed a model that includes trauma (blunt fracture in the fashion of Bonnarens and Einhorn), surgical stabilization (standardized intramedullary K-wire fixation), and infection (Staphylococcus aureus inoculum). In this two-part study, we found that 10(2) colony-forming units of inoculum produced an optimal infection rate of 90-100%, which substantially challenged the immune system without overwhelming sepsis. We hypothesized that, in traumatic fractures, there is a specific immunological response that may lead to an increased rate of infection. In Part 2, we demonstrated immunosuppression (decreased Interleukin-12 levels) at days 6, 10, and 12 after fracture fixation versus nonfractured control groups (p < 0.05). This study describes a rat model of femur factures with osteomyelitis that allows investigation of posttraumatic immunosuppression.
Lindsey
Brock A
BA
Department of Orthopaedics, West Virginia University, P.O. Box 9196, Health Sciences Center, Morgantown, West Virginia 26506-9196, USA. blindsey@hsc.wvu.edu
Clovis
Nina B
NB
Smith
E Suzanne
ES
Salihu
Sydha
S
Hubbard
David F
DF
D000818:Animals; D004195:Disease Models, Animal; D005264:Femoral Fractures / Q000097:blood / Q000382:microbiology*; D005597:Fractures, Open / Q000097:blood / Q000382:microbiology*; D018664:Interleukin-12 / Q000097:blood; D008297:Male; D010019:Osteomyelitis / Q000097:blood / Q000382:microbiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013203:Staphylococcal Infections / Q000097:blood / Q000382:microbiology*; D013211:Staphylococcus aureus
D018664:Interleukin-12