Multilevel anterior cervical discectomy and fusion with and without rhBMP-2: a comparison of dysphagia rates and outcomes in 150 patients

Clinical article

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Object

Reported complications of recombinant human bone morphogenetic protein–2 (rhBMP-2) use in anterior cervical discectomy and fusion (ACDF) cases include dysphagia and cervical swelling. However, dysphagia often occurs after multilevel ACDF procedures performed with allograft (without BMP) as well. To date, there has been no large study comparing the dysphagia rates of patients who have undergone multilevel ACDF using allograft spacers with those who underwent ACDF using polyetheretherketone (PEEK) cages filled with rhBMP2. The authors report one of the first such comparisons between these 2 patient cohorts.

Methods

The authors retrospectively reviewed 150 patient records. Group 1 (BMP group) consisted of 100 patients who underwent multilevel ACDF with PEEK cages filled with rhBMP-2 and instrumented with a cervical plate. Group 2 (allograft group) included a matched control cohort of 50 patients who underwent multilevel ACDF with allograft spacers and anterior plate fixation (without rhBMP-2). Patient demographics were not significantly different between the groups. Fusion was assessed by means of dynamic radiographs and/or CT at routine intervals. Complications, dysphagia incidence, standardized dysphagia score, Nurick grades, and fusion rates were assessed.

Results

The mean follow-up for the BMP group (Group 1) was 35 months while the mean follow-up for the allograft group (Group 2) was 25 months. There was a complication rate of 13% in the BMP group compared with 8% in the allograft group (p < 0.005). There was no significant difference in overall dysphagia incidence between the BMP group and the allograft group (40% vs 44%, respectively; p > 0.05). However, there was a significant difference in the severity of dysphagia (using the SWAL-QOL dysphagia scoring system) between the 2 groups: 0.757 for the BMP group versus 0.596 for the allograft group (p < 0.005). In subgroup analysis, the use of rhBMP-2 significantly increased the severity of dysphagia in patients undergoing 2-level ACDF (p < 0.005). However, the severity of dysphagia did not differ significantly between groups when 3- or 4-level ACDF cases were compared. There was no pseudarthrosis in Group 1 (the BMP group) compared with a 16% pseudarthrosis rate in Group 2 (the allograft group) (p < 0.05). There was a weak correlation between the total rhBMP-2 dose and the dysphagia score (Kendall tau rank correlation coefficient 0.166, p = 0.046).

Conclusions

The use of rhBMP-2 in patients undergoing 2-level ACDF significantly increases the severity of dysphagia (dysphagia score) without affecting the overall incidence of dysphagia. However, there is no statistically significant difference in the incidence or severity of dysphagia between patients undergoing 3-level or 4-level ACDF treated with PEEK/rhBMP-2 and those treated with only allograft. The use of rhBMP-2 appears to reduce the risk of pseudarthrosis. This benefit is most pronounced in patients who undergo 4-level ACDF and are smokers.

Abbreviations used in this paper:ACDF = anterior cervical discectomy and fusion; PEEK = polyetheretherketone; PEG = percutaneous endoscopic gastrostomy; rhBMP-2 = recombinant human bone morphogenetic protein–2; UCSF = University of California, San Francisco.

Article Information

Address correspondence to: Daniel C. Lu, M.D., Ph.D., Department of Neurosurgery, University of California, Los Angeles, 650 Charles E. Young Drive South, CHS 74-129, Los Angeles, California 90095. email: DCLu@mednet.ucla.edu.

Please include this information when citing this paper: published online November 16, 2012; DOI: 10.3171/2012.10.SPINE10231.

© AANS, except where prohibited by US copyright law.

Headings

Figures

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    Photographs of a PEEK cage filled with a sponge soaked in rhBMP-2 (left) and structural allograft spacer (right).

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    Lateral dynamic flexion (left) and extension (right) radiographs demonstrating solid fusion at 6 months subsequent to a 3-level ACDF procedure with PEEK cages and rhBMP-2.

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    Radiographs obtained 1 year postoperatively in a patient who underwent a 4-level ACDF procedure. A: Lateral radiograph demonstrating a 4-level ACDF with possible pseudarthrosis at C6–7. B and C: Coronal (B) and sagittal (C) CT reconstructions confirming the pseudarthrosis at C6–7.

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    Anteroposterior (A) and lateral (B) radiographs obtained in a patient with a 4-level ACDF associated with dysphagia and cervical swelling. This patient required reexploration of the surgical site on the 5th postoperative day for drainage of a seroma. A subsequent anteroposterior radiograph of an esophagram demonstrated dysmotility related to swelling (C). Note the blockage of dye at the upper portion of the construct. Despite this swelling-induced dysmotility, the patient did not require a PEG and had complete resolution of his dysphagia 6 weeks after his initial surgery.

References

  • 1

    Bazaz RLee MJYoo JU: Incidence of dysphagia after anterior cervical spine surgery: a prospective study. Spine (Phila Pa 1976) 27:245324582002

    • Search Google Scholar
    • Export Citation
  • 2

    Bennett MReynolds ASDickerman RD: Recent article by Shields et al titled “adverse effects associated with high-dose recombinant human bone morphogenetic protein-2 use in anterior cervical spine fusion.”. Spine (Phila Pa 1976) 31:202920302006. (Letter)

    • Search Google Scholar
    • Export Citation
  • 3

    Boakye MMummaneni PVGarrett MRodts GHaid R: Anterior cervical discectomy and fusion involving a polyetheretherketone spacer and bone morphogenetic protein. J Neurosurg Spine 2:5215252005

    • Search Google Scholar
    • Export Citation
  • 4

    Boden SDZdeblick TASandhu HSHeim SE: The use of rhBMP-2 in interbody fusion cages. Definitive evidence of osteoinduction in humans: a preliminary report. Spine (Phila Pa 1976) 25:3763812000

    • Search Google Scholar
    • Export Citation
  • 5

    Burkus JK: Bone morphogenetic proteins in anterior lumbar interbody fusion: old techniques and new technologies. J Neurosurg Spine 1:2542602004

    • Search Google Scholar
    • Export Citation
  • 6

    Burkus JKGornet MFDickman CAZdeblick TA: Anterior lumbar interbody fusion using rhBMP-2 with tapered interbody cages. J Spinal Disord Tech 15:3373492002

    • Search Google Scholar
    • Export Citation
  • 7

    Burkus JKHeim SEGornet MFZdeblick TA: The effectiveness of rhBMP-2 in replacing autograft: an integrated analysis of three human spine studies. Orthopedics 27:7237282004

    • Search Google Scholar
    • Export Citation
  • 8

    Burkus JKSandhu HSGornet MF: Influence of rhBMP-2 on the healing patterns associated with allograft interbody constructs in comparison with autograft. Spine (Phila Pa 1976) 31:7757812006

    • Search Google Scholar
    • Export Citation
  • 9

    Carlisle EFischgrund JS: Bone morphogenetic proteins for spinal fusion. Spine J 5:6 Suppl240S249S2005

  • 10

    Giannoudis PVDinopoulos HTsiridis E: Bone substitutes: an update. Injury 36:Suppl 3S20S272005

  • 11

    Heary RFSchlenk RPSacchieri TABarone DBrotea C: Persistent iliac crest donor site pain: independent outcome assessment. Neurosurgery 50:5105172002

    • Search Google Scholar
    • Export Citation
  • 12

    Kaiser MGMummaneni PVMatz PGAnderson PAGroff MWHeary RF: Radiographic assessment of cervical subaxial fusion. J Neurosurg Spine 11:2212272009

    • Search Google Scholar
    • Export Citation
  • 13

    Lanman THHopkins TJ: Early findings in a pilot study of anterior cervical interbody fusion in which recombinant human bone morphogenetic protein-2 was used with poly(L-lactideco-D,L-lactide) bioabsorbable implants. Neurosurg Focus 16:3E62004

    • Search Google Scholar
    • Export Citation
  • 14

    McHorney CARobbins JLomax KRosenbek JCChignell KKramer AE: The SWAL-QOL and SWAL-CARE outcomes tool for oropharyngeal dysphagia in adults: III. Documentation of reliability and validity. Dysphagia 17:971142002

    • Search Google Scholar
    • Export Citation
  • 15

    Patel VVZhao LWong PKanim LBae HWPradhan BB: Controlling bone morphogenetic protein diffusion and bone morphogenetic protein-stimulated bone growth using fibrin glue. Spine (Phila Pa 1976) 31:120112062006

    • Search Google Scholar
    • Export Citation
  • 16

    Perri BCooper MLauryssen CAnand N: Adverse swelling associated with use of rh-BMP-2 in anterior cervical discectomy and fusion: a case study. Spine J 7:2352392007

    • Search Google Scholar
    • Export Citation
  • 17

    Samartzis DShen FHGoldberg EJAn HS: Is autograft the gold standard in achieving radiographic fusion in one-level anterior cervical discectomy and fusion with rigid anterior plate fixation?. Spine (Phila Pa 1976) 30:175617612005

    • Search Google Scholar
    • Export Citation
  • 18

    Shields LBRaque GHGlassman SDCampbell MVitaz THarpring J: Adverse effects associated with high-dose recombinant human bone morphogenetic protein-2 use in anterior cervical spine fusion. Spine (Phila Pa 1976) 31:5425472006

    • Search Google Scholar
    • Export Citation
  • 19

    Smucker JDRhee JMSingh KYoon STHeller JG: Increased swelling complications associated with off-label usage of rhBMP-2 in the anterior cervical spine. Spine (Phila Pa 1976) 31:281328192006

    • Search Google Scholar
    • Export Citation
  • 20

    Tomford WW: Bone allografts: past, present and future. Cell Tissue Bank 1:1051092000

  • 21

    Tumialán LMPan JRodts GEMummaneni PV: The safety and efficacy of anterior cervical discectomy and fusion with polyetheretherketone spacer and recombinant human bone morphogenetic protein-2: a review of 200 patients. J Neurosurg Spine 8:5295352008

    • Search Google Scholar
    • Export Citation

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