Smoking has been shown to impair the success of spinal fusion surgery: it makes the vertebrae less likely to fuse and raises the risk of complications. At the same time, it is one of the factors you yourself can change the most. Below I set out honestly what we know about this — and what you can do for the success of your own operation.
The aim of spinal fusion surgery is for two or more vertebrae to fuse into a solid bony union, so that the affected segment becomes stable. In this sense the operation is successful when that fusion takes place. If it does not, a pseudarthrosis (a “false joint”, also called nonunion) can develop: the bones do not unite properly, which can cause lasting pain and sometimes makes a further operation necessary. You can read more about fusion on the spine stabilization page.
The reason is mainly physiological. Nicotine narrows the blood vessels, and the carbon monoxide in cigarette smoke reduces the oxygen-carrying capacity of the blood. As a result, less blood and oxygen reach the healing bone — exactly where it is needed most. This is why bone formation starts more slowly and with more difficulty.
This can be shown in figures, too: in smokers the chance that the fusion fails to unite is roughly 1.9 times higher than in non-smokers. The risk is present in both single- and multi-level surgery, and regardless of whether the patient’s own bone or donor bone is used.
The effect of smoking does not stop at bone formation. It also increases the likelihood of a repeat operation, and raises the risk of other complications around surgery: wound infection, increased strain on the adjacent spinal segment, and — in cervical surgery — difficulty swallowing. These do not occur inevitably, but they are more common with smoking.
And now the most important point, which is up to you: quitting helps. In an analysis of tens of thousands of patients, those who stopped smoking around the time of surgery had fewer complications than active smokers — and non-smokers had the fewest of all.
One thing, however, I must add honestly. Quitting does not erase the increased risk: there is not yet enough evidence that, on its own, it fully restores the chance of fusion. But on the grounds of both the biology of bone healing and clinical experience, quitting is the single most effective thing you can contribute to the success of your operation — and the longer you stay smoke-free, the better.
It is best to start well in advance: ideally at least four weeks before surgery, and to maintain it for at least four weeks afterwards. Best of all is to stay smoke-free throughout the first six months of healing — while the bone is fusing.
One important practical consideration: do not leave quitting to the last moment, just before the operation. Stopping abruptly right before the procedure can in fact increase the risks around surgery — for example those related to the airway and anaesthesia. It is therefore worth quitting in a planned way, well ahead of time, and discussing the timing with your surgeon and anaesthetist, so that there is enough time to prepare.
The success of an operation is genuinely shared work: alongside the surgery itself, your preparation matters a great deal. The most you can do is to quit smoking. Beyond that, other factors you can influence also help: a healthy body weight, regular exercise suited to your condition, and — if you have diabetes — good control of your blood sugar. I write about these in detail on the patient journey page. The aim is not to apportion blame, but for you to begin your operation with the best possible odds.
If I quit, will the fusion definitely unite?
It cannot be guaranteed, but quitting noticeably improves your chances and reduces the risk of complications. It is the most you yourself can contribute to a successful outcome.
Is it enough to quit on the day of surgery?
No. It is best to start quitting well in advance, ideally at least four weeks before surgery; stopping at the very last moment, just before the operation, is not advisable. Discuss the timing with your doctor.
Are e-cigarettes or nicotine replacement a solution?
Nicotine itself is part of the problem, because it narrows the blood vessels, so nicotine-containing products are not a real solution either. The goal is to give up nicotine as well. It is worth discussing the options, and support for quitting, with your doctor.
How long do I need to stay smoke-free?
From the weeks before surgery through the first six months of healing, while the bone is fusing. The longer, the better.
If I cannot quit, does that mean I cannot have surgery?
The decision is always made individually, together, at the consultation. This is not about setting conditions: the aim is for you to be aware of the risks and to begin your operation with the best possible odds.
If you are facing spine surgery, or are still considering it, at the consultation we will review your situation together and plan how you can best prepare for it — including the timing of quitting smoking.
This article draws on the following professional sources: