en Spine Research <div style="text-align: justify;"><strong>Background and Aim: </strong>Modic changes are alterations in the spine endplates and subchondral bone shock absorption, seen by magnetic resonance imaging (MRI). No studies have investigated the effect of vitamin D and alendronate as oral drugs on reducing and modifying Modic changes after degenerative spine fusion surgery. This study aimed to evaluate the efficacy of oral vitamin D and alendronate administration in patients with low back pain, and Modic changes undergoing lumbar fusion surgery.<br> <strong>Methods and Materials/Patients:</strong> A total of 81 middle age women with a normal range of serum vitamin d were enrolled in three groups who underwent lumbar fusion surgery according to neurosurgical criteria. Group 1 (n=27) received additional oral alendronate, group 2 (n=27) received oral vitamin D for six months postoperatively, and group 3 (n=27) received no drug (except simple analgesics and antibiotics). The patients were followed up with a visual analog scale (VAS) and Oswestry disability index (ODI). MRI was done before and six months after surgery.<br> <strong>Results:</strong> There was no significant difference between the three groups in VAS and ODI scores (P=0.416, P=0.601, respectively), but the mean VAS and ODI in all three groups decreased over six months, which was statistically significant (P<0.001). Modic changes in all three groups changed significantly over 6 months (P<0.01). In the vitamin D and alendronate groups, Modic type 3 increased significantly, but Modic type 2 and Modic type 1 decreased significantly in the vitamin d and no medication groups, respectively.<br> <strong>Conclusion:</strong> Oral vitamin D administration has a desirable effect not only on clinical outcomes after lumbar spinal fusion surgery because of degenerative surgery but also on vertebral endplate Modic changes compared to oral bisphosphonate.</div> Oral vitamin D, Alendronate efficacy, Modic changes, Lumbar fusion 0 0 http://irjns.org/browse.php?a_code=A-10-34-10&slc_lang=en&sid=1 Kaveh Haddadi 10031947532846008529 10031947532846008529 No Orthopedic Research Center, Mazandaran University of Medical Sciences, Sari, Iran Mahmoud Mehriyari 10031947532846008530 10031947532846008530 No Student Research Committee, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran Saeed Ehteshami 10031947532846008531 10031947532846008531 No Orthopedic Research Center, Mazandaran University of Medical Sciences, Sari, Iran Sajjad Shafiee 10031947532846008532 10031947532846008532 No Neurosurgery Department, Imam Hospital, Mazandaran University of Medical Sciences, Sari, Iran Ahmad Ghasemi 10031947532846008533 10031947532846008533 No Department of Radiology, Imam Hospital, Mazandaran University of Medical Sciences, Sari, Iran Leila Asadian 10031947532846008534 10031947532846008534 No Student Research Committee, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran Mohsen Aarabi Mohsen.aarabi@gmail.com 10031947532846008535 10031947532846008535 Yes Azad University (IR) in Oxford, Oxford, UK AND Department of Family Medicine, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran