25.
EFORT12-2819 Microdialysis and Laser Doppler flow measurements
in the femoral head in patients with dislocated femoral neck fractures, one
year follow up
Morten Foged Bøgehøj, Claus Emmeluth, Søren Overgaard
Ortopædkirugisk afd O Odense Universitets Hopsital; Ortopædkirugisk afd O,
Odense Universitets Hopsital; Ortopædkirugisk afd O, Odense Universitets
Hopsital
Background:
We state that preserving the hip might be optimum in treatment
of patients with dislocated femoral neck fractures presuming that the fractures
unite. We hypothesized that lack of blood flow and development of ischemia
might influence the outcome of the osteosynthesis. In this study we established
microdialysis and laser Doppler measurements in patients with a dislocated
femoral neck fractures.
Purpose / Aim of Study:
To establish microdialysis measurements and laser
Doppler measurements in the femoral head of patients with a dislocated
femoral neck fracture and to follow the patients one year after operation.
Materials and Methods:
20
patients with dislocated fractures of the femoral
neck were osteosynthezised by using 2 cannulated screws. During surgery
blood flow was measured with laser Doppler in order to detect pulsatile flow,
and microdialysis was performed to detect ischemia. Both measurements were
performed in the femoral head and with the greater trochanter as control. The
parameters measured by microdialysis were lactate, pyruvate, glycerol, and
glucose concentrations. Measurements were done after the fracture was
reduced, and during osteosynthesis. The patients were followed for one year
after operation.
Findings / Results:
In all but one patient laser Doppler showed pulsatile flow
in the greater trochanter, whereas only 11 patients had flow in the femoral
head. The values for glucose in the trochanter and the femoral head were 3.8
mM(1.3) and 2.5 mM(1.4) (p<0.001) respectively, and for glycerol 0.17
mM(0.08) and 0.36 mM(0.20) (p<0.001). During the observation period 7 of
20
patients were re operated, all with hemiarthroplsty. The association between
laser Doppler measurements and the Microdialysis measurements was poor.
The association between reoperation and ischemia or laser Doppler was also
poor.
Conclusions:
This is the first time that laser Doppler and microdialysis has
been established in patients with dislocated femoral neck fractures. We showed
reduced flow and ischemia in the femoral head. The poor associations between
high lactate/puruvate ration and failure might explain that failure after
osteosynthesis of the femoral neck fracture is multifactorial. Further studies
will have to evaluate whether laser Doppler and microdialysis in combination
with fracture related parameters can predict failure of the osteosynthesis. This
might enable us to establish a treatment algorithm to be used in the daily clinic.
