Authors: Mladen Djurasovic Leah Y Carreon Charles H Crawford III Jason D Zook Kelly R Bratcher Steven D Glassman
Publish Date: 2012/03/03
Volume: 21, Issue: 8, Pages: 1616-1623
Abstract
Spinal fusion as a treatment for degenerative disc disease is controversial Prior authors have identified various MRI findings as being pain generators which might help guide patient selection for lumbar fusion procedures These findings have included disc desiccation disc contour highintensity zone annular disruption the presence of Modic endplate changes and disc space collapse The purpose of this study is to investigate which MRI findings in patients with degenerative disc disease predict clinical improvement with lumbar fusionA singlecenter surgical database of patients undergoing lumbar fusion was reviewed for patients whose indication for fusion surgery was primary disc pathology We identified 51 patients 71 disc levels who had completed 2year prospectively collected outcomes questionnaires and had preoperative MRIs available for review NRS 0–10 back and leg pain Oswestry Disability Index ODI and SF36 Physical Composite Summary scores were obtained preoperatively and at 1 and 2year followup MRIs were reviewed by three fellowshiptrained spine surgeons who were asked to grade them for the following five characteristics a disc desiccation b disc contour c presence of a highintensity zone HIZ annular tear d presence of Modic endplate changes and e disc height Twoyear outcome measures were compared to MRI findings to identify which findings correlated with improvement in outcome scoresStatistically significant improvements were noted in back pain leg pain SF36 PCS and ODI in the group overall Disc desiccation disc contour presence of an HIZ lesion and the presence of Modic endplate changes did not correlate with 2year outcomes Disc height was correlated with 2year change in outcome measures Discs with preoperative height less than 5 mm demonstrated a 234 point ODI improvement compared to 92 points for discs 7 mm Similarly SF36 PCS improved 95 points in discs 5 mm compared to 07 in discs greater than 7 mm Discs between 5 and 7 mm demonstrated intermediate levels of improvementSeveral commonly utilized MRI criteria proposed as indications for lumbar fusion do not seem to correlate with 2year improvement in clinical outcomes Discs which are narrowed and collapsed preoperatively demonstrate better improvement at 2 years postoperatively as compared to discs which have maintained disc height Significant disc space collapse may represent a subset of “degenerative disc disease” which responds more favorably to treatment with fusionMD receives consulting fees from Medtronic LYC receives research support from Norton Healthcare CHC receives consulting fees from Medtronic and Alphatec and is on the Speakers bureau for Synthes SDG receives royalties from Medtronic and research support from Norton Healthcare MD LYC CHC KRB and SDG are employees of Norton Healthcare JDZ has nothing to disclose
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