J Buchholz
Surgical Clinic Wermelskirchen, Wermelskirchen, Germany

FX Huber, PJ Meeder
Division of Trauma and Plastic Surgery, Department of Surgery, Heidelberg University, Heidelberg, Germany

G Muhr
Trauma Center Bergmannsheil, Bochum University, Bochum, Germany

GK Kreitz, L Herzog
Department of Surgery, Kirnitzschtal-Klinik, Kirnitzschtalstraße 6, Bad Schandau, Germany

PURPOSE. To study high-energy phosphates in cortical bone through experiments on inbred white New Zealand rabbits.

METHODS. Tibial fractures were induced in 80 rabbits and then stabilised by screw osteosynthesis. After 3 (group A; n=40) or 7 days (groups B; n=40), the defective tissue was covered by local muscle flaps. At increasing intervals (from 1 to 16 weeks), the screws were removed and the animals were euthanised (n=8 per group). The bone was removed and analysed histomorphologically; adenosine triphosphate (ATP) levels were determined by high-performance liquid chromatography.

RESULTS. The mean ATP concentration in healthy cortical bone at 16 weeks was 0.092 (standard error, 0.009) nmol/mg dry mass, which was significantly higher than that in the group with delayed healing: 0.081 (0.011) nmol/mg in group A and 0.005 (0.001) nmol/mg in group B (paired t test, p<0.05). Earlier healing led to lower rates of necrosis (0 vs 38; groups A vs B) and osteomyelitis.

CONCLUSION. Early muscle-flap coverage can revascularise the cortical bone, which is reflected in the higher ATP content in the cortical bone measured by high-performance liquid chromatography. Measuring changes of ATP levels can help investigate the metabolism of the pathological bone.