There are relatively few prevalence studies looking at lumbar spondylolisthesis, and none have combined radiographs, MRI, and a clinical evaluation. Dr. Ishimoto and his colleagues from Japan involved in the Wakayama Spine Study sought to fill this void by performing a population-based cross-sectional study that evaluated 938 participants over the age of 40. All subjects underwent standing x-rays, lumbar MRI, and a clinical evaluation to determine the presence of back pain, leg pain, and neurogenic claudication. About two thirds of the patients were female, and the average age was 67. Spondylolisthesis was defined as antero- or retrolisthesis greater than 5% of the length of the superior endplate of the caudal vertebra in the motion segment, and both degenerative (DS) and isthmic spondylolisthesis (IS) were included. Thirteen percent of males and 17% of females had spondylolisthesis, and this difference was not statistically significant. Low back pain was about 20% more prevalent in the spondylolisthesis subjects (47% vs. 38%), though this difference did not reach significance either. Symptomatic spinal stenosis, defined as the presence of at least moderate stenosis on MRI and radiculopathy or claudication symptoms, was more than twice as prevalent in patients with listhesis (16% vs. 7%), and nearly three times as common in men with listhesis (20% vs. 8%). The average slip was measured at 14%, and the degree of slip was not related to the presence of symptomatic stenosis.
This paper is a nice cross-sectional study of lumbar spondylolisthesis and represents the first time where a population-based study evaluating lumbar spondylolisthesis included radiographs, MRI, and clinical evaluation. Their findings of nearly equal prevalence among men and women was surprising given that previous studies have found symptomatic DS to be nearly twice as common among women.1 This study did include a mixture of IS, DS, and retrolisthesis (primarily at L3-L4) subjects, so it is possible that the sex-based prevalence differences in DS observed previously were obscured by the inclusion of IS and retrolisthesis patients. Another possibility is that the sex-based prevalence differences in DS are less pronounced in the Japanese population. The major weakness of this paper was the failure to stratify most of the analyses by type of listhesis (i.e. IS, DS, retrolisthesis) as patient characteristics and presenting symptoms can be different among those three subgroups. The association between spondylolisthesis and symptomatic stenosis is not surprising as listhesis of any kind tends to develop with stenosis (i.e. DS tends to cause central and lateral recess stenosis, IS tends to cause foraminal stenosis, and retrolisthesis can cause stenosis in all compartments). The lack of a strong association with low back pain is also not that surprising as listhesis itself does not necessarily cause back pain, but the degenerative changes that accompany it do. As such, the prevalence of back pain is probably similar or only slightly higher in a spondylolisthesis cohort as compared to an age-matched cohort without listhesis (assuming a similar degree of degenerative changes). This finding is in-line with a previous study that showed a similar degree of back and leg pain across spinal stenosis patients stratified by the presence of DS.2 The cross-sectional design of this study limits us to a snapshot in time, so how the radiographic and clinical findings change over time remains unknown. The authors promise a follow-up report in 3 years, which should be illuminating.
Please read Dr. Ishimoto's paper in the June 1 issue. Does this change how you view the association between spondylolisthesis and clinical symptoms? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor
1. Weinstein JN, Lurie JD, Tosteson TD, et al. Surgical versus nonsurgical treatment for lumbar degenerative spondylolisthesis. The New England journal of medicine 2007;356:2257-70.
2. Pearson A, Blood E, Lurie J, et al. Degenerative spondylolisthesis versus spinal stenosis: does a slip matter? Comparison of baseline characteristics and outcomes (SPORT). Spine (Phila Pa 1976) 2010;35:298-305.