Journal of Neurosurgery: Spine. 13:562–567, November 2010

Clinical article

What happens to Modic changes following lumbar discectomy? Analysis of a cohort of 41 patients with a 3- to 5-year follow-up period

Ralph Rahme, M.D., Ronald Moussa, M.D., Rabih Bou-Nassif, M.D., Joseph Maarrawi, M.D., Ph.D., Tony Rizk, M.D., Georges Nohra, M.D., Elie Samaha, M.D., and Nabil Okais, M.D. Department of Neurosurgery, Hôtel-Dieu de France, Saint-Joseph University, Beirut, Lebanon. ©1944-2010 by the American Association of Neurosurgeons

Abbreviations used in this paper: MC = Modic change; ODI = Oswestry Disability Index; VAS = visual analog scale.

Object
The natural history of Modic changes (MCs) in the lumbar spine is often marked by conversion from one type to another, but their course following lumbar discectomy remains unknown. The authors sought to study the impact of surgery on the natural history of these lesions.

Methods
Forty-one patients treated with lumbar microdiscectomy between 2004 and 2005 were enrolled in this study and underwent clinical evaluation and repeat MR imaging after a median follow-up of 41 months (range 32–59 months). Preoperative and follow-up MR images were reviewed and the type, location, and extent of MCs at the operated level were recorded and compared.

Results
The study population consisted of 27 men and 14 women with a mean age of 54 years (range 24–78 years). During the follow-up period, the prevalence of MCs increased from 46.3% to 78%, and 26 patients (63.4%) had Type 2 lesions at the operated level. Of the 22 patients without MCs, 4 (18.2%) converted to Type 1 and 9 (40.9%) to Type 2. Of the 5 Type 1 lesions, 3 (60%) converted to Type 2, and 2 (40%) remained Type 1 but increased in size. In contrast, none of the 14 Type 2 changes converted to another type, although 10 (71.4%) increased in extent. There were no reverse conversions to Type 0.

Conclusions
Following lumbar discectomy, most patients develop Type 2 changes at the operated level, possibly as a result of accelerated degeneration in the operated disc. Neither the preoperative presence of MCs nor their postoperative course appears to affect the clinical outcome.