Retrospective lumbar fusion outcomes measured by ODI sub-functions of 100 consecutive procedures

Low back pain has been quite prevalent in the general population. Chronic low back pain can be defined as back pain lasting for more than 12 weeks. For chronic symptoms, fusion surgeries are the most common surgeries to alleviate the pain. Visual Analog Scale (VAS) is a measurement for subjective characteristics or attitudes that can be difficult to be directly measured. Respondents specify their level of agreement to a statement by indicating a position along a continuous line between two end points.

The purpose of this study is to investigate patient-reported pain using our own modified ODI with sub-functions. This allowed the study to show how patient outcomes differ with and without co-morbidity as well as functional outcomes after spinal fusion for degenerative disk disease (DDD) with the consistency of using one device and all procedures performed by the same surgeon.

One hundred patients with DDD were treated with spinal fusion using one device. All procedures were performed by the same surgeon over a 3-year period. Patients were evaluated with discography and MRI preoperatively. Diagnosis of DDD was made when imaging showed bony segment erosion with decreased disc space >50%. Fifty-six patients participated in the initial questionnaire and their data were tabulated and statistically analyzed. Twenty male patients aged 49-85 (median: 67, mean: 66), and thirty-six female patients aged 30-84 (median: 67, mean 64) responded to the questionnaire. There were no differences in pain total by gender, fusion level, single/multiple fusions, degenerative versus deformity condition, type of graft, and lumber area (all p values ≥ 0.15).

Five-year pain measurements used by the VAS questionnaire as well as pain and functional outcomes measured by the ODI after lumbar fusion were superior to the results at 2 years (p = 0.025). Improvement was seen in all of the ODI sub-scores after 5 years, however, only physical function and social function reached statistical significance (p = 0.016 and 0.061, respectively).

Successful outcomes were demonstrated for each of the categories assessed and no statistical differences were seen in the ODI % for any comparison after 5 years on 19% of data reported which may have limited forecast reliability. Our data suggest that post-operative outcome is independent of preoperative condition, procedure to be preformed, age, and BMI. Our data support the continual practice of spinal fusion for the treatment of degenerative disk disease.