Does Spinal Fusion Surgery Work Effectively?

The answer to this question must be a resounding yes based on the increasing frequency of spinal fusion surgeries in the United States. As many as 1.5 million spinal fusion surgeries are performed in the United States annually according to the latest data available for 2023. However, this number is likely the number of fused levels and not necessarily the number of patients undergoing fusions. It is estimated that ~ 488,000 spinal fusion cases are completed in the US with most common type of spinal fusion being in the lumbar spine with nearly 350,000 fusions.

Fusions in the cervical spine are also common with 132,000 anterior cervical discectomy/fusions performed annually. Thoracic fusions are the least common in comparison with ~ 24,000 surgeries completed. In comparison, ~ 18,000 spinal fusions are performed in the UK annually within the National Health Service with a population of 68.35 million in 2023. This means that ~ 3.8 fusions are completed in the UK per capita. In comparison, the United States population in 2023 was 334.9 million.  This translates into 686 fusions per capita in the US which is 180X the number.

The natural follow up question is how can there be such a large disparity in relatively comparable countries in terms of economic development? There are several obvious factors that limit spinal fusions in the UK. The first is the socialized system that simply does not allow spinal fusion to be performed for degenerative spinal conditions. This is the most common reason spinal fusions are performed in the US. Instead, the conditions that are deemed necessary for spinal fusions in the UK are for fractures, infections and tumors. These conditions are mostly acute and require stabilization due to mechanical and or neurological instabilities.

Given this background, I always tell my patients that being offered a spinal fusion is a double-edged sword. The downside is that the surgery may not be strictly necessary and may not help. The upside is that Americans are at least given a choice to potentially get better from debilitating neck or back pain that has not responded to conservative measures.  So although many American patients may feel burdened by having to choose whether to have a spinal fusion or not, in a way, this freedom of choice is a privilege not available in most countries.

This is a somewhat long-winded answer to the question of whether spinal fusion surgeries work. The answer is YES, but not every patient. Most studies estimate the improvement to be in ~ 70% of patients with a range of 50-80%. However, some studies show no long-term improvement compared to conservative treatments. The reason for the conflicting data is that all reported papers are limited by weakness in the study designs which may include small sample size and limited follow up. The biggest limitation is the retrospective nature and lack of controls which are the most important factors in a scientific study.

The bottom line is that surgical fusions should be considered in some patients but not all.  This should be determined by a surgeon who possesses the skill and experience to choose the right patient at the right time.