Every median sternotomy performed for open-heart surgery leaves behind a bone that must heal under real mechanical stress, from breathing and coughing to simply sitting up in bed. Sternal plate fixation is one method surgeons use to close and stabilize that bone, relying on rigid titanium hardware rather than traditional wire loops. This article explains how sternal plate systems are constructed, how they function biomechanically, and which situations lead a surgical team to consider them.
What Is a Sternal Plate Fixation System?
A sternal plate fixation system generally consists of one or more titanium or titanium alloy plates that span the sternotomy, secured to each half of the sternum with multiple screws. Rather than compressing the bone edges together with a wire loop, as in traditional cerclage closure, the plate creates a rigid bridge across the fracture-like gap left by the sternotomy, sharing load between the plate and the underlying bone as it heals. Plates are typically contoured to fit the natural curvature of the sternum and may be positioned longitudinally, transversely, or in a combination pattern depending on the surgeon's preference and the specific sternotomy.
How Does Rigid Fixation Support Sternal Stability?
The biomechanical premise behind rigid plate fixation is straightforward: by screwing a stiff plate into bone on both sides of the sternotomy, the construct resists the small back-and-forth motion, sometimes called micromotion, that can occur at a healing bone interface under mechanical stress. Reducing this motion is thought to support a more stable healing environment, similar to principles used in fracture fixation elsewhere in the skeleton. This rigidity is one reason plate systems are sometimes considered for patients whose bone quality or clinical risk factors make a less stable closure more concerning.
Who Might Be Considered for Plate Fixation Instead of Wires?
Surgeons may consider rigid plate fixation for patients carrying elevated risk for sternal complications, including those with osteoporosis, diabetes, obesity, chronic obstructive pulmonary disease with a strong cough, or a history of prior sternal wound issues. Patients undergoing reoperative sternotomy, where the bone has already been divided once before, are sometimes also considered candidates given the altered bone quality often present at reoperation. The decision is individualized, and a qualified surgeon weighs these factors against the added procedural time and cost of a plating system for any specific patient.
What Does the Titanium Material Contribute?
Titanium and titanium alloys are favored for sternal plate systems because they combine mechanical strength with a strong biocompatibility profile and relative compatibility with medical imaging, including reduced artifact on CT scans compared with some other metals. Titanium implants are generally well tolerated as permanent hardware, and infection or clinically significant reaction to the material itself is uncommon, though any surgical hardware carries some risk of infection tied to the overall surgical site rather than the metal specifically. More background on titanium fixation devices used in cardiac and other surgical fields is available on the cardiac surgery instruments category page.
Does Rigid Fixation Reduce Dehiscence Risk?
Sternal dehiscence, a separation of the healing sternum, is a recognized complication of any sternal closure method, and reducing its incidence is one of the motivations behind rigid fixation systems. Some published surgical literature has reported associations between rigid plate fixation and lower rates of dehiscence in specific high-risk populations, though results vary by study population and surgical technique, and outcomes depend on many factors beyond the fixation hardware alone, including wound care, nutrition, and patient activity after surgery. No fixation method eliminates the risk of dehiscence entirely, and any concerning wound symptoms after sternotomy warrant prompt evaluation by the surgical team.
Can someone with a sternal plate undergo an MRI safely?
Titanium implants are generally considered compatible with MRI, though safety depends on the specific device and scanner parameters. Patients should inform their imaging center about any implanted hardware before an MRI is scheduled so appropriate precautions can be confirmed.
Device availability and regulatory status vary by country. Please contact INVAMED or your authorized local distributor for current regulatory information applicable to your region.