Laser doppler flow imaging of open lower leg fractures in an animal experimental model.
OBJECTIVE
Open lower leg fractures are frequently associated with severe soft tissue damage, followed by osteomyelitis. Using an animal experimental model, we investigated the effect of timing of coverage of a tibial fracture with a local muscle flap.


METHODS
80 rabbits had a tibial fracture induced in a standardised fashion, which was stabilised by screw osteosynthesis. After 3 (group A; n=40) and 7 days (group B; n=40), respectively, the tissue defect was covered by a local gastrocnemius flap. In increasing intervals from 1 to 2, 4, 8, and 16 weeks, the rabbits from each group were killed and the bone fracture was analysed histomorphologically. Cortical microcirculation was measured by 2-channel laser doppler flowmetry.


RESULTS
Muscle flaps after 3 days improved perfusion significantly as compared with 7 days (24 Flux [standard error, 5 Flux] versus 10 Flux [3 Flux]; baseline, 1.4 Flux). Group A animals also displayed a lower rate of necrosis (0 versus 38). The incidence of osteomyelitis was higher in group B than in group A (24% versus 0%).


CONCLUSIONS
Laser doppler flowmetry was proven to be a reliable, minimally invasive means for identifying avital tissue, leading to reduction in the loss of vital bone tissue in experimental settings.
Herzog
L
L
Division of Trauma and Plastic Surgery, Department of Surgery, Heidelberg University, Im Neuenheimer Feld 110, 69120 Heidelberg, Germany. JT8@ix.urz.uni-heidelberg.de
Huber
F X
FX
Meeder
P J
PJ
Muhr
G
G
Buchholz
J
J
D000818:Animals; D001863:Bone Screws; D004195:Disease Models, Animal; D017078:Laser-Doppler Flowmetry; D008833:Microcirculation; D009132:Muscles / Q000637:transplantation; D009336:Necrosis; D010019:Osteomyelitis / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology; D011817:Rabbits; D012039:Regional Blood Flow; D013524:Surgical Flaps / Q000098:blood supply*; D013977:Tibia / Q000098:blood supply* / Q000601:surgery; D013978:Tibial Fractures / Q000601:surgery*