Rationale and Options for Choosing an Optimal Closure Technique for Primary Midsagittal Osteochondrotomy of the Sternum, Part 2: A Theoretical and Critical Review of Techniques and Fixation Devices.

The intact one-piece sternum is indispensible to the thorax for its normal physiological biomechanics. To overcome tri-planar forces acting on the sternum following midsagittal osteochondrotomy, it must be reconstructed using an optimal technique to withstand distraction loads of normal respiration and violent cough. It should be fixed rigidly to reconstitute the anterior coronal column of the axial skeleton to maintain erect posture and prevent kyphosis. Sterile or infective non-union of the sternum compromises the physical endurance of patients and has an immense psychological effect. From an engineering perspective, there is no substantially proven gold standard technique to fix a divided sternum. Stainless steel wire applied in various configurations to a variety of shapes and sizes has become an acceptable standard of care due to its long-standing history and cost-effectiveness. Recently there has been a proliferation of innovative techniques to deal with primary and failed union of the sternum in an effort to prevent mechanical failure and serious deep surgical wound infection progressing to mediastinitis. Among the newer implant designs, the ones currently in use are shaped like clamps and clasps to compress the sternal halves together as well as alphabet-shaped mini-plating systems. In this section of the review series, mechanisms, pros and cons of currently available implants to reconstruct the bisected sternum, and external support systems considered necessary in high-risk clients are discussed.