title: The relationship between serum vitamin D levels and spinal fusion success: a quantitative analysis.
abstract: METHODS
  An in vivo dosing study of vitamin D in a rat posterolateral spinal fusion model with autogenous bone grafting. Rats randomized to 4 levels of vitamin D-adjusted rat chow, longitudinal serum validation, surgeons/observers blinded to dietary conditions, and rats followed prospectively for fusion endpoint.
  
  
  OBJECTIVE
  To assess the impact of dietary and serum levels of vitamin D on fusion success, consolidation of fusion mass, and biomechanical stiffness after posterolateral spinal fusion procedure.
  
  
  BACKGROUND
  Metabolic risk factors, including vitamin D insufficiency, are often overlooked by spine surgeons. Currently, there are no published data on the causal effect of insufficient or deficient vitamin D levels on the success of establishing solid bony union after a spinal fusion procedure.
  
  
  METHODS
  Fifty rats were randomized to 4 experimentally controlled rat chow diets: normal control, vitamin D-deficient, vitamin D-insufficient, and a nontoxic high dose of vitamin D, 4 weeks prior to surgery and maintained postsurgery until sacrifice. Serum levels of 25(OH)D were determined at surgery and sacrifice using radioimmunoassay. Posterolateral fusion surgery with tail autograft was performed. Rats were sacrificed 12 weeks postoperatively, and fusion was evaluated via manual palpation, high-resolution radiographs, micro-computed tomographic scans, and biomechanical testing.
  
  
  RESULTS
  Serum 25(OH)D and calcium levels were significantly correlated with vitamin D-adjusted chow (P < 0.001). There was a dose-dependent relationship between vitamin D-adjusted chow and manual palpation fusion, with greatest differences found in measures of radiographical density between high and deficient vitamin D (P < 0.05). Adequate levels of vitamin D (high and normal control) yielded stiffer fusion than inadequate levels (insufficient and deficient) (P < 0.05).
  
  
  CONCLUSIONS
  Manual palpation fusion rates increased with supplementation of dietary vitamin D. Biomechanical stiffness, bone volume, and density were also positively related to vitamin D and calcium.
  
  
  METHODS
  N/A.
authors: *Biomechanics Laboratory †Spine Center, and ‡Spine Tissue Engineering Laboratory, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA.
authors: Melodie F
authors: MF
authors: Metzger
authors: Linda E A
authors: LE
authors: Kanim
authors: Li
authors: L
authors: Zhao
authors: Samuel T
authors: ST
authors: Robinson
authors: Rick B
authors: RB
authors: Delamarter
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002118:Calcium / Q000097:blood; D002762:Cholecalciferol / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013123:Spinal Fusion; D013131:Spine / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications; D014815:Vitamins / Q000008:administration & dosage*; D055114:X-Ray Microtomography
chemical_list: D014815:Vitamins; D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D; D002118:Calcium
references: Bone. 2009 May;44(5):893-8
references: 19442605
references: J Orthop Res. 1998 Nov;16(6):650-3
references: 9877387
references: Arch Intern Med. 2009 Mar 23;169(6):551-61
references: 19307517
references: Endocrinology. 1998 Oct;139(10):4319-28
references: 9751515
references: Endocrinology. 1997 Nov;138(11):4629-35
references: 9348188
references: Arch Orthop Trauma Surg. 1997;116(5):271-4
references: 9177802
references: Endocrinology. 1996 Apr;137(4):1358-64
references: 8625911
references: Calcif Tissue Int. 1994 Dec;55(6):443-50
references: 7895183
references: J Bone Miner Res. 1992 Aug;7(8):863-75
references: 1442201
references: Clin Chim Acta. 2006 Jun;368(1-2):48-52
references: 16480702
references: Calcif Tissue Int. 2006 May;78(5):257-70
references: 16622587
references: N Engl J Med. 2006 Feb 16;354(7):669-83
references: 16481635
references: Spine (Phila Pa 1976). 2005 Feb 15;30(4):468-74
references: 15706346
references: Calcif Tissue Int. 2004 Sep;75(3):183-8
references: 15386160
references: Spine J. 2009 Jul;9(7):537-44
references: 19328744
references: Connect Tissue Res. 2009;50(4):256-62
references: 19637061
references: J Prosthodont. 2009 Aug;18(6):473-8
references: 19486459
references: J Bone Miner Res. 2010 Feb;25(2):305-12
references: 19594303
references: Clin Endocrinol (Oxf). 2010 Sep;73(3):277-85
references: 20796001
references: J Bone Joint Surg Am. 2010 Oct 6;92(13):2300-4
references: 20926724
references: J Biomech. 2011 Jan 11;44(2):213-20
references: 21071030
references: J Pediatr Orthop. 2011 Apr-May;31(3):331-3
references: 21415696
references: J Orthop Surg (Hong Kong). 2012 Apr;20(1):18-22
references: 22535805
references: J Heart Lung Transplant. 2012 Jul;31(7):700-7
references: 22386448
references: Spine (Phila Pa 1976). 2013 Mar 15;38(6):507-15
references: 22986835
references: Autoimmun Rev. 2013 Aug;12(10):976-89
references: 23542507
references: Nutrients. 2013 Sep;5(9):3605-16
references: 24067388
references: JAMA Surg. 2014 Feb;149(2):112-8
references: 24284777
references: Int Orthop. 2014 Jul;38(7):1499-504
references: 24737149
references: Spine (Phila Pa 1976). 2006 Sep 15;31(20):2329-36
references: 16985461
references: J Orthop Trauma. 2007 Sep;21(8):557-70
references: 17805023
references: Am J Clin Nutr. 2008 Aug;88(2):513S-519S
references: 18689393
references: Osteoporos Int. 2008 Sep;19(9):1283-90
references: 18373057
references: J Am Board Fam Med. 2009 Jan-Feb;22(1):69-74
references: 19124636
references: J Orthop Res. 1999 Sep;17(5):795
references: 10569495
references: J Bone Miner Res. 2001 Aug;16(8):1408-15
references: 11499863
references: Med J Aust. 2002 May 6;176(9):438-9
references: 12056998
references: Age Ageing. 2004 Jan;33(1):45-51
references: 14695863
references: Acta Orthop Scand. 1983 Dec;54(6):805-9
references: 6689464
references: Arch Orthop Trauma Surg. 1984;103(4):257-62
references: 6548905
references: Bone. 1989;10(2):117-23
references: 2788448
references: Proc Natl Acad Sci U S A. 1991 May 1;88(9):3657-60
references: 2023915
references: Clin Orthop Relat Res. 1992 Nov;(284):80-90
references: 1395317