BACKGROUND: Sternal dehiscence occurs when steel wires pull through sternal 
bone. This study tests the hypothesis that closure stability can be improved by 
jacketing sternal wires with stainless steel coils, which distribute the force 
exerted on the bone over a larger area.
METHODS: Midline sternotomies were performed in 6 human cadavers (4 male). Two 
sternal closure techniques were tested: (1) approximation with six interrupted 
wires, and (2) the same closure technique reinforced with 3.0-mm-diameter 
stainless steel coils that jacket wires at the lateral and posterior aspects of 
the sternum. Intrathoracic pressure was increased with an inflatable rubber 
bladder placed beneath the anterior chest wall, and sternal separation was 
measured by means of sonomicrometry crystals. In each trial, intrathoracic 
pressure was increased until 2.0 mm of motion was detected. Differences in 
displacement pressures between groups were examined at 0.25-mm intervals using 
the paired Student's t test.
RESULTS: The use of coil-reinforced closures produced significant improvement in 
sternal stability at all eight displacement levels examined (p < 0.03). Mean 
pressure required to cause displacement increased 140% (15.5 to 37.3 mm Hg) at 
0.25 mm of separation, 103% (34.3 to 69.8 mm Hg) at 1.0 mm of separation, and 
122% (46.8 to 103.8 mm Hg) at 2.0 mm of separation.
CONCLUSIONS: Reinforcement of sternal wires with stainless steel coils 
substantially improves stability of sternotomy closure in a human cadaver model.