Is a randomised trial of decompression plus fusion versus decompression alone for patients with spinal stenosis feasible?
As people age, there is increasing wear on the bones (vertebrae) in the spine. The spine responds by producing extra bone in some areas, changing its shape in others and sometimes with one vertebra slipping on another. All these changes can narrow the normal spaces where the nerves pass from the spinal cord. When the nerves get pressed, back and leg pain occurs with substantial interference on daily life and on mental and physical well-being. When severe, surgery may be necessary to relieve that pressure. This is now the most common spinal disorder requiring surgery. 18,000 procedures are performed each year in the NHS.
Surgical treatment can involve removing the bone that presses on the nerves. Or it could also involve the insertion of screws and rods (called an instrumented fusion) to make the spine straighter and stronger to achieve long term benefit. There is no agreement between surgeons as to which is better. The instrumented fusion operations are more complex and need to account for the variability in how individual patients are affected. Unfortunately, there is very limited evidence for patients and surgeons to make an informed choice.
Ultimately a research study called a randomised trial is needed to inform this decision but such a trial will not be easy to conduct. Before we do a large study like this we need to consider how best to run it and if it will work in practice. We need to know if patients and surgeons would be willing to take part, how they feel about the two different operations and how we should measure “success” after the operation. This is called a feasibility study and will tell us if a larger study is possible and how it should be run to give us an answer.