Sternal resynthesis in patients with postoperative sterno-mediastinitis

The aim of the study was to evaluate efficacy and safety of sternal resynthesis by nitinol implants in patients with poststernotomy sternomediastinitis and in animal model. Material and Methods. Surgical nitinol alloy wire mesh implant was developed for sternal resynthesis. The experimental study comprised 60 Wistar rats: sternal tissue was cut by lancet, nitinol alloy wire mesh implant was placed, and wound was closed by suturing layer by layer (experimental animal group). Control animal group comprised sham-operated rats. The signs of swelling, hemorrhage, hyperemia, inflammatory infiltration, regeneration, and reaction to implant were studied histologically at days 14, 28, and 48 post-surgery. Clinical results of surgical treatment for postoperative sternomediastinitis were studied in 29 patients hospitalized during 5-year period (2010-2014). Patients were assigned to 2 groups. Group 1 - n=14; mean age of 62.64±7.69 years; 10 (71.4%) males - underwent sternal resynthesis with placement of nitinol alloy wire mesh implant. Group 2 - n=15; mean age of 61.07±7.86 years; 11 (73.3%) males - underwent surgical debridement with metallo-osteosynthesis (MOS) by metallic suture. Results. Six-week experimental animal study demonstrated no significant adverse reactions between the implant and sternal and parasternal soft tissues. In clinical group 1, successful sternal closure was achieved in 12 patients; mediastinitis resolved in 12 patients; healing by primary intention was observed in 11 patients. No implant-specific complications (fracture, migration, cheese-wiring, severe pain syndrome) were recorded. In group 2, successful sternal closure was achieved in 6 patients; mediastinitis resolved in 8 patients; healing by primary intention was observed in 10 patients. Routine MOS in patients with postoperative complications of medial sternotomy failed to achieve sternal closure in 60% of cases due to failed metallic sutures that aggravated sternal fragmentation. Recurrence of failed sternal sutures occurred more frequently in patients who received routine MOS (р<0.05). Uneventful postoperative period was observed more often in group 1 (р<0.05). There was significant association between the development of failed sternal closure and preceding attempt of routine MOS in group 1 (р<0.05). In both groups of patients, there was a significant association between the development of recurrent mediastinitis and recurrent failure of sternal closure (p<0.05). Conclusion. Six-week experimental animal study did not reveal adverse interactions between proposed implant and sternal and parasternal soft tissues. Clinical study demonstrated that method of sternal resynthesis, based on surgical nitinol alloy wire mesh implant, provided good early results and safe fixation of sternal fragments. However, this method is contraindicated in patients with severe sternal fragmentation. Efficacy of the proposed method exceeded that of routine MOS.

послеоперационный стерномедиастинит, ресинтез грудины, никелид титана, пористый сетчатый имплантат, postoperative sternomediastinitis, sternal resynthesis, nitinol, nitinol alloy wire mesh implant

1. Вишневский А.А., Рудаков С.С., Миланов Н.О. и др. Хирургия грудной стенки: руководство. - М.: Видар-М, 2005. - 301 с.

2. Материалы с памятью формы и новые технологии в медицине / под ред. В.Э. Гюнтера. - Томск: Изд-во МИЦ, 2010. - 360 с.

3. Broadhurst J., Moorjani N., Ohri S. Traumatic fracture of nitinol thermoreactive sternal clips // Interact. Cardiovasc. Thorac. Surg. - 2010. - Vol. 10(3). - P. 465-466.

4. Gucu A., Toktas F., Eris C. et al. Nitinol thermoreactive clips for secondary sternal closure in cases of noninfective sternal dehiscence // Tex. Heart. Inst. J. - 2012. - Vol. 39(4). - P. 513516.

5. Hountis P., Chountis M., Hatziveis K. et al. The hanuman syndrome and the greater omentum’s transposition for the management of mediastinitis // Official Journal of Balkan Military Medical Committee. - 2012. - Vol. 15, No. 4. - P. 289-297.

6. Meeks M.D., Lozekoot P.W., Verstraeten S.E. et al. Poststernotomy mediastinitis and the role of broken steel wires: retrospective study // Innovations (Phila). - 2013. - Vol. 8(3). - P. 219-224.

7. Olbrecht V.A., Barreiro C.J., Bonde P.N. et al. Clinical outcomes of noninfectious sternal dehiscence after median sternotomy // Ann. Thorac. Surg. - 2006. - Vol. 82(3). - P. 902-907.

8. Plass A., Grunenfelder J., Reuthebuch O. et al. New transverse plate fixation system for complicated sternal wound infection after median sternotomy // Ann. Thorac. Surg. - 2007. -Vol. 83. - P. 1210-1212.

9. Sergio F., Herrera A.M., Atehortua M. et al. Use of steel bands in sternotomy closure: implications in high-risk cardiac surgical population // Interact. Cardiovasc. Thorac. Surg. - 2009. -Vol. 8. - P. 200-205.

10. Song D.H., Lohman R.F., Renucci J.D. et al. Primary sternal plating in high-risk patients mediastinitis // Eur. J. Cardiothorac. Surg. - 2004. - Vol. 26(2). - P. 367-372.

11. Tavlasoglu M., Kurkluoglu M., Arslan Z. et al. Detachment and dislocation of thermoreactive clips from sternum in late postoperative period due to misuse // Interact. Cardiovasc. Thorac. Surg. - 2012. - Vol. 14(4). - P. 491-493.

12. The Parisian Mediastinitis Study Group. Risk factors for deep sternal wound infection after sternotomy: a prospective multicenter study // J. Thorac. Cardiovasc. Surg. - 1996. -Vol. 111. - P. 1200-1207.