PhD ThesisThe British military was engaged in combat operations in Iraq and Afghanistan over a
12-year period from 2003 to 2014. It has been asserted that over this time survival
after combat injury improved generating a cohort of patients with complex limb
injuries, including open fractures, which are prone to infection and challenging to
reconstruct.
Using an anatomic measure of injury severity I demonstrate an improvement in
survival after combat injury. I further tested this finding by devising a military specific
version of an anatomic-physiological injury scoring system, which confirmed the
survival improvement.
The UK military trauma registry was used to determine that the most frequently
fractured bone was the Tibia and 65% of these fractures were open. Of these, 23%
were surgically treated for infection in the first year and S. aureus bacteria was the
causative organism in 60%. Infection was significantly associated with amputation or
unplanned revision surgery.
To further investigate open fracture infections in a controlled setting, an established
rodent model of a stabilised, S. aureus contaminated, femoral defect was refined.
This model was used to investigate the relationship between timing of treatment and
infection. The results of this study indicate that delaying antibiotics administration has
a greater effect on infection rates than delaying surgery and that early antibiotics can
reduce the greater infection seen with surgical delay but not negate its effect entirely.
Novel treatments with potential to reduce infection in open fractures were then
evaluated. Chlorhexidine was found to be similar to saline for wound irrigation with
respect to preventing infection. A novel biodegradable antibiotic gel proved to be
superior at preventing infection in the model than the existing clinical standard local
antibiotic delivery vehicle: bone cement (Polymethylmethacrylate) beads. Finally
Bismuth Thiols were demonstrated to potentiate the effect of antibiotics in preventing
infection