Performance of a novel sternal synthesis device after median and faulty sternotomy: mechanical test and early clinical experience.

BACKGROUND

Reinforcement of chest closure may be required in patients with multiple risk factors of wound dehiscence. Performance of a light, size-adaptable closure reinforcement device (DSS: Sternal Synthesis Device; Mikai SpA, Vicenza, Italy) is presented.

METHODS

A longitudinal median or paramedian incision was performed in artificial sternal models: closure was accomplished with simple interrupted steel wires or reinforced with the DSS. Forces required for separation of the rewired sternal halves during a monotonic tensile test were analyzed. A high velocity traction cycles test was also adopted to simulate the impact of coughing.

RESULTS

After median incision, ultimate load values inducing break of the sternum models were 580 +/- 35 N (Newton) in controls; failure of the test occurred at 1,200 +/- 47 N in the reinforced group (p = 0.0002). More lateral displacement of sternal halves at increasing forces was observed in controls (p = 0.0001). After paramedian incision, ultimate load values inducing break of the constructs were lower in controls (220 +/- 20 N vs 500 +/- 25 N, p = 0.001), which also showed more lateral displacement of sternal halves than the reinforced group (p = 0.002). At the high velocity traction cycles test, the number of cycles required to break the models was lower in controls (2,250 +/- 35 vs 3,855 +/- 48 cycles, p = 0.0001). Preliminary clinical experience in 45 patients showed ease of implantation and low risk of complications.

CONCLUSIONS

The proposed sternal reinforcement device provides substantial sternal support at electromechanical testing after median and faulty sternotomy and may hopefully prevent sternal wires migration and bone fractures in high risk patients.