The condition of one muscle group before surgery has a measurable effect on how well you do afterwards. Here is why it matters and what can be done about it.
If lumbar spine surgery is being considered for you, it is worth understanding why two patients with the same diagnosis, operated on by the same surgeon, can have quite different recoveries. A good deal of the explanation lies in a muscle group many patients have never heard of.
The multifidus muscle
The multifidus is a group of muscles running along the back of the spine, linking the segments together and stabilising the spine.
When these muscles are used poorly, or barely used at all, they become infiltrated with fat. This shows up clearly on an MRI scan. In a patient using the muscle well, the muscles at the back of the spine appear uniform in colour, a sign of healthy muscle. Where there has been some lack of use, patches of white fat begin to appear within the muscle. In severe cases, where the muscle is genuinely not being used, that fat deposition becomes extensive.
The spine itself is structurally strong. But the muscles supporting it still matter a great deal, particularly in your recovery after an operation.
A cycle that is rarely anyone’s fault
The lack of use is usually unintentional. When you are in significant pain, the multifidus is one of the first muscles to become inhibited. Less use leads to more fat infiltration, which further degrades the quality of the muscle, and so the cycle continues.
What the research shows
Two studies illustrate the point well.
The first looked at patients who had previously undergone lumbar fusion surgery, dividing them into those with significant ongoing pain afterwards and those with much better pain control. When the researchers examined muscle quality on MRI scans taken before surgery, the group who went on to do well had noticeably better muscle quality to begin with.
The second looked at patients having surgery for spinal stenosis, either a decompression to remove the thickened structures compressing the nerves, or a distraction operation, where a device is placed between the bones to pull them slightly apart and create space around the nerves. Those with fat infiltration of the multifidus specifically, and not the other muscles, did worse than those whose multifidus was healthier. These patients were followed up for around five years.
It is important to be clear about what these studies do and do not say. Neither suggests that surgery does not work. They show that the quality and conditioning of the muscles supporting your spine affects your outcome. That is a meaningful distinction.
Prehabilitation
Where a scan shows poor multifidus condition, this is where prehabilitation comes in. It involves:
- Targeted strengthening
- Neuromuscular control and conditioning
- Psychological preparation
It also means optimising your general health more broadly. Is your diabetes well controlled? Are there heart conditions we can address? Is your blood pressure where it should be?
A team approach
I believe strongly in a surgeon providing clinical direction to a team of experts looking after you.
A practical example: a pain specialist can inject specific targets to give you a window of better pain control, during which you can work with a physiotherapist on exercises to stimulate and reactivate the multifidus. In more extreme cases, where activating the muscles yourself is simply too painful, a special stimulator can be used to do it for you.
The key takeaway
Surgery is only part of the picture. The condition you arrive in matters, and in the weeks before an operation there is often a good deal that can be done to improve it.
If surgery is on the horizon for you, this is a conversation worth having early rather than late.
