Sternal wires are intended to be permanent. The vast majority of people who undergo open heart surgery through a median sternotomy keep their wires for the rest of their lives without any issues. The wires hold the two halves of the breastbone together while bone healing occurs, and once that healing is complete, they simply stay in place, biologically inert and doing no harm. That said, a small but real percentage of patients end up needing their wires removed, and the reasons why tell you a lot about how these little pieces of metal interact with the human body over years and decades.
Why Wires Are Still the Standard
Median sternotomy, where the breastbone is split lengthwise down the middle, is one of the most common bone-cutting procedures performed worldwide. It gives surgeons wide access to the heart and great vessels for procedures like coronary artery bypass grafting, valve replacements, and aortic repairs. After the cardiac work is done, the two halves of the sternum need to be brought back together and held in place. For the overwhelming majority of patients, that job falls to stainless steel wires.
Wires have dominated sternal closure for decades because they check nearly every practical box: they are cheap, fast to place, easy to handle, and associated with a relatively low complication rate. Surgeons typically thread a series of wires around or through the sternal halves, then twist or crimp them tight to hold the bone edges together. Common configurations include simple interrupted wires and figure-of-eight patterns. A biomechanical study found that the most rigid wire closure, a multitwist technique, allowed only about 0.37 mm of displacement under a 20 kg load, while figure-of-eight wires allowed roughly 1.2 mm under the same force.
Despite being a remarkably simple technology in an era of sophisticated cardiac devices, wire closure has proven hard to dethrone. Alternatives exist, and we will get to those, but the fact that cardiothoracic surgery remains the only surgical specialty routinely using basic wire approximation for a major bone closure says something about how well it works for most patients.
What Happens to the Wires Over Time
Once the sternum heals, typically over six to eight weeks for the initial bony union, the wires become essentially redundant. The bone itself bears the mechanical load of your chest wall, and the wires just sit there. Stainless steel surgical wire is chosen specifically because it resists corrosion in the body’s salty, slightly acidic environment. These alloys are designed to last a lifetime without degrading in a way that causes problems.
That said, “designed to last” does not mean “guaranteed never to corrode.” A study examining stainless steel sternal wires after long-term implantation found that corrosion can occur, though it tends to be localized and, for most patients, clinically insignificant.1PubMed. Corrosion of stainless steel sternal wire after long-term implantation The body forms a thin fibrous capsule around each wire, effectively walling it off from surrounding tissue. For the typical patient, sternal wires become a permanent, forgotten part of their anatomy. They show up on every chest X-ray and CT scan you ever have afterward, but that is usually the extent of their presence in your life.
When Wires Need to Come Out
The reasons surgeons remove sternal wires cluster into a few categories, and persistent chest pain is by far the most common trigger. Pain along the sternum after heart surgery is not unusual in the early months, but when it lingers well beyond the expected healing period and other causes have been ruled out, the wires themselves become a suspect. In a study of 95 patients who had wires removed for persistent anterior chest wall pain, 13 also had wire-related infection contributing to the problem.2European Journal of Cardio-Thoracic Surgery. The outcome of sternal wire removal on persistent anterior chest wall pain after median sternotomy – Section: Results
The main reasons wires are removed include:
- Chronic pain: Wire ends can poke into surrounding tissue, or the wire itself can sit against a nerve or sensitive area of the periosteum. Some patients describe a specific, localized tenderness that they can point to with one finger.
- Infection: Deep sternal wound infections, while uncommon, sometimes require wire removal as part of the treatment. The wires can harbor bacteria in biofilms that antibiotics alone cannot clear.
- Wire breakage: Repeated mechanical stress from breathing, coughing, and upper body movement can fatigue the metal over time, and a broken wire end can migrate or irritate tissue.
- Sternal nonunion: If the bone fails to heal properly, the wires may cut through weakened bone. This is more common in patients with osteoporosis or those who had complicated postoperative courses.
- Allergic reaction: Nickel hypersensitivity, discussed below, can cause ongoing inflammation around the wires.
It is worth emphasizing that these scenarios represent a minority of patients. Most people who have a sternotomy never think about their wires again after recovery.
The Nickel Allergy Problem
Stainless steel surgical wire contains nickel, and nickel allergy is surprisingly common. Estimates suggest that up to about 15% of the general population has some degree of nickel hypersensitivity, often from exposure to jewelry or belt buckles.3PubMed. Sternal Wires-Induced Severe Systemic Inflammatory Response and Cardiac Tamponade Most people with a mild contact allergy to nickel do fine with sternal wires because the exposure is internal rather than on the skin surface, and the amount of nickel leaching from surgical-grade stainless steel is very small. But in some patients, the immune response is significant enough to cause persistent pain, swelling, or worse.
One early case report described a patient whose chronic sternal pain was attributed to nickel sensitivity in the wires, after other causes had been excluded.4PubMed. Sternal wire-induced persistent chest pain: a possible hypersensitivity reaction More dramatically, a case report documented a 48-year-old woman with a known metal contact allergy who developed a severe systemic inflammatory response and cardiac tamponade after coronary artery bypass grafting, attributed to the sternal wires.3PubMed. Sternal Wires-Induced Severe Systemic Inflammatory Response and Cardiac Tamponade That is an extreme case, but it underscores a question that has lingered in the field for decades: among the many patients who have unexplained persistent chest pain after sternotomy, how many are actually reacting to the nickel in their wires?
If you know you have a nickel allergy before surgery, it is worth discussing with your surgeon. Titanium wires or alternative closure methods that avoid nickel-containing alloys are available, though they are not standard at every institution.
What Removal Surgery Looks Like and How Well It Works
Wire removal is a relatively minor procedure compared to the original heart surgery, but “minor” is a relative term when you are reopening a sternotomy incision. The surgeon typically makes an incision over the original scar, locates the wire ends, untwists them, and pulls them free. It can sometimes be done under local anesthesia for superficial wires, though general anesthesia is common when multiple wires are being removed or when deeper access is needed.
The good news is that outcomes are generally favorable when patients are selected appropriately. In a study following patients who had wires removed for persistent pain, about 86% reported complete or partial relief of their symptoms, while roughly 11% reported no change and 3% actually felt worse.5PubMed. The outcome of sternal wire removal on persistent anterior chest wall pain after median sternotomy – Section: RESULTS A separate study found similar results: among 186 patients available for follow-up after wire removal, 83% achieved complete pain relief and another 10% had improvement.6PubMed. Does removal of steel wires relieve post-sternotomy pain after cardiac surgery? – Section: RESULTS
Those numbers look encouraging, but the roughly one in ten patients who get no relief remind us that diagnosing the wires as the true pain source is not always straightforward. Post-sternotomy pain can stem from the bone itself, from costochondral junctions, from nerve damage during the original surgery, or from musculoskeletal strain. If the wires are not actually the culprit, removing them will not help.
Risks of Removing the Wires
Wire removal is not without hazard, particularly when infection is involved. A study on major bleeding during deep sternal wound treatment found that in some cases, bleeding occurred during or after wire removal itself. In that series, four patients bled during the removal surgery, while in 11 others, bleeding developed anywhere from 15 minutes to 15 days afterward, with shearing forces on weakened tissue the most common cause.7PubMed. Major bleeding complicating deep sternal infection after cardiac surgery – Section: RESULTS The structures directly behind the sternum, including the heart, bypass grafts, and the internal mammary arteries, make any reoperation in this area higher-stakes than it might seem for what is essentially pulling out a few pieces of wire.
For patients without infection whose sternum has healed solidly, the risk profile is much more favorable. But surgeons still approach wire removal carefully, especially in patients who have had multiple prior sternotomies or who have vascular grafts running just beneath the bone.
Sternal Wires in Children
Children who undergo heart surgery for congenital defects face a slightly different calculation. Their skeletons are still growing, and hardware placed across a growing sternum can cause problems that adults never encounter. A study comparing wire and cable closure in pediatric patients found that none of the children in the wire group needed removal for pain during follow-up, while about 10% of those closed with cables (a thicker, braided alternative to simple wire) did require removal due to chest wall pain.8The Journal of Thoracic and Cardiovascular Surgery. Sternal wire removal in pediatric patients: Wire versus cable sternotomy closure
Even so, the growing chest wall means pediatric patients may be more likely than adults to eventually feel the hardware as their body changes. Surgeons who operate on children are generally aware of this and may choose closure techniques with easier future removal in mind.
Plates, Clips, and Other Alternatives
Although wire closure remains the default, rigid plate fixation has been gaining ground, particularly for patients at higher risk of sternal complications. These titanium plates are screwed directly into the bone on either side of the sternotomy, providing a much more rigid fixation than wires can achieve. The tradeoff is higher upfront cost and a somewhat more involved placement procedure.
The evidence comparing the two approaches is growing. A retrospective study found that plate fixation was associated with significantly lower rates of sternal dehiscence compared to wire closure: 3.4% versus 11.6%.9PubMed Central. Rigid plate fixation versus wire cerclage for sternal closure after coronary artery bypass grafting: a retrospective cohort study – Section: RESULTS Patients with plates also had shorter hospital stays. Another study found that even though patients selected for plate fixation had higher baseline risk factors (higher body mass, more diabetes, more bilateral internal mammary artery grafts), all 37 readmissions for sternal wound complications in the study occurred in the wire group.10PubMed. Wire Cerclage Versus Rigid Plate Fixation: A Retrospective Cohort Study and Cost-Benefit Analysis on Method of Sternotomy Closure After Cardiac Surgery – Section: RESULTS
Like wires, plates are designed to be permanent. The difference is that plates hold the bone rigidly rather than just approximating the edges, which may be particularly valuable in patients whose bone quality is poor or whose body habitus puts extra stress on the healing sternum.
Another option gaining attention is thermoactive nitinol clips. Nitinol is a nickel-titanium alloy that changes shape in response to temperature, allowing the clips to be placed and then tightened by warming them to body temperature. One advantage of nitinol clips is that they do not integrate into the bone the way screws do, which makes removal fast and straightforward even years after implantation.11PubMed Central. THERMOACTIVE NITINOL CLIPS AS PRIMARY AND SECONDARY STERNAL CLOSURE AFTER CARDIAC SURGERY – FIRST EXPERIENCE IN SLOVENIA – Section: Discussion For patients with known nickel sensitivity, though, nitinol clips present the same concern as stainless steel wires, since the alloy contains nickel.
Wire Fatigue and Breakage
Your sternum is not a quiet piece of bone. Every breath expands and contracts the rib cage, every cough sends a sudden jolt through it, and every time you push yourself up from a chair or reach for something overhead, the closure hardware absorbs some of that force. Over thousands of repetitions, metal can fatigue.
A biomechanical study investigating wire fatigue found that under cyclic loading, wires failed by several mechanisms: the twisted ends became untwisted, the wire fractured at the twist point, or it fractured where it contacted a cannulated screw. Only the test with the lowest peak force survived to six million cycles without failing.12PubMed Central. Fatigue strength of a wire passing through a cannulated screw: implications for closure of the sternum following cardiac surgery In clinical practice, wire breakage is not especially common, but it does happen, and a broken wire can migrate or create a sharp end that pokes into tissue. If you develop new localized chest wall pain years after your surgery, a simple chest X-ray can usually reveal whether a wire has broken or shifted.
Living with Sternal Wires Long-Term
For the practical-minded patient heading home after heart surgery, a few things are worth knowing about your new permanent hardware. Sternal wires are generally considered safe for MRI scans. They are non-ferromagnetic enough that they will not move or heat significantly in a standard MRI machine, though they can cause some local image distortion on the scan itself. You should always tell any imaging facility that you have sternal wires, but in practice they rarely prevent you from getting an MRI when you need one.
Airport metal detectors and security scanners are a common worry. Sternal wires may or may not set off a metal detector, depending on the sensitivity of the machine and how many wires you have. Some patients carry a card from their surgeon, though these are not universally provided and security personnel are generally familiar with surgical hardware. It is more of a minor inconvenience than a real problem.
You may occasionally feel the wires, particularly in thin patients where the twisted wire ends sit just beneath the skin. Some people can feel a small bump or ridge along their sternotomy scar, especially in cooler weather when tissue contracts slightly. This is normal and does not indicate a problem unless it becomes painful or the skin over a wire end becomes red or thin.
Sternal Nonunion and When Wires Are Not Enough
In a small number of patients, the sternum does not heal properly after surgery, a condition called sternal nonunion. These patients often describe a clicking or grinding sensation in the chest, along with pain that worsens with upper body movement. Sternal nonunion is associated with significant discomfort and functional limitation, and it is one situation where simply removing the wires is not the answer, because the bone needs more fixation, not less.13PubMed Central. Late complications of chest wall reconstruction: management of painful sternal nonunion
Treatment for symptomatic nonunion typically involves removing the failed hardware, cleaning out any non-viable bone and tissue, and then re-fixing the sternum with a more robust method. This might involve rigid plates, cables, or a combination of techniques. The goal is stable fixation that allows the bone a second chance to unite. Risk factors for nonunion include obesity, diabetes, chronic obstructive pulmonary disease, osteoporosis, and use of bilateral internal mammary artery grafts, which reduce blood supply to the sternum.
For patients who develop nonunion, the original wires have essentially failed their mechanical purpose, even if they have not physically broken. The wires may have gradually cut through weakened bone, leaving the sternal halves mobile despite the hardware still being intact. Recognizing this distinction matters: the presence of intact wires on an X-ray does not guarantee that the sternum beneath them is solidly healed.