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Mobility provocation radiostereometry in anterior cervical spine fusions


This study aimed to evaluate the use of mobility-provocation radiostereometry (RSA) in anterior cervical spine fusions and compare the results to deformation studies on the same patients and plain flexion-extension radiographs. Mobility-provocation RSA was used to evaluate anterior cervical spine fusions in 45 patients. The motions recorded at 3 and 12 months postoperatively were compared to RSA measurements of deformation of the fusion over time and to plain flexion-extension radiographs in the same patients taken 3 months postoperatively. Studies of rotations from right to left revealed ten cases with significant motion at 3 months, and three at 12 months. With motion from flexion to extension, ten cases showed significant motion at 3 months and three at 12 months. In only three cases was the mobility-provocation RSA considered to add any information on the stability of the fusions compared to that obtained with the deformation studies. In 37 patients mobility-provocation radiography in flexion-extension using conventional technique was done to evaluate the accuracy. The mean difference between angular motions recorded on plain radiographs and rotations around the transverse axis in flexion to extension recorded with RSA was 1.6° (range 0.04°–8.04°, SD 2.1°). The corresponding 95% and 99% confidence limits for the difference between the two methods were 5.8° and 7.2°. The study showed that the use of mobility-provocation RSA did not add any information over that obtained by deformation RSA studies. Conventional radiography is too inaccurate to measure inducible displacement in this patient population.

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  1. Cauthen CC, Kinard RE, Vogler JB, et al (1998) Outcome analysis of noninstrumented anterior cervical discectomy and interbody fusion in 348 patients. Spine 2:188–192

    Google Scholar 

  2. Drerup B (1985) Improvements in measuring vertebral rotation from the projections of the pedicles. J Biomech 18:369–378

    CAS  PubMed  Google Scholar 

  3. Kärrholm J (1989) Roentgen stereophotogrammetry. Review of orthopedic applications. Acta Orthop Scand 60:491–503

    PubMed  Google Scholar 

  4. Kärrholm J, Herberts P, Hultmark P, Nivbrant B, Thanner J (1997) Radiostereometry of hip prostheses: review of methodology and clinical results. Clin Orthop 344:94–110

    PubMed  Google Scholar 

  5. Lind B, Sihlbom H, Nordwall A, Malchau H (1989) Normal range of motion of the cervical spine. Arch Phys Med Rehabil 70:692–695

    CAS  PubMed  Google Scholar 

  6. Malchau H, Kärrholm J, Wang YX, Herberts P (1995) Accuracy of migration analysis in hip arthroplasty. Digitized and conventional radiography, compared to radiostereometry in 51 patients. Acta Orthop Scand 66:418–424

    CAS  PubMed  Google Scholar 

  7. Panjabi M, Chang D, Dvorak J (1992) An analysis of errors in kinematic parameters associated with in vivo functional radiographs. Spine 17:200–205

    CAS  PubMed  Google Scholar 

  8. Penning L (1964) Nonpathologic and pathologic relationship between the lower cervical spine vertebrae. AJR 91:1036–1050

    CAS  Google Scholar 

  9. Robinson RA, Smith GW (1955) Anterolateral cervical disc removal and interbody fusion for the cervical disc syndrome. Bull Johns Hopkins Hosp 96:223–224

    Google Scholar 

  10. Selvik G (1989) Roentgen stereophotogrammetry. A method for the study of the kinematics of the skeletal system. Acta Orthop Scand 60 [Suppl 232]

  11. Söderkvist I (1993) Computing parameters in nonlinear least squares models. Thesis, University of Umeå

  12. White AA, Southwick WO, Panjabi MM (1976) Clinical instability in the lower cervical spine: a review of past and current concepts. Spine 1:15–18

    Google Scholar 

  13. Whitecloud T (1989) Management of radiculopathy and myelopathy by the anterior approach. In: Cervical Research Society (eds) The Cervical Spine. Lippincott, Philadelphia, pp 644–658

  14. Zoëga B, Kärrholm J, Lind B (1998) One-level cervical spine fusion with or without plate fixation: a randomized study using radiostereometry in 27 cases. Acta Orthop Scand 69:363–368

    CAS  PubMed  Google Scholar 

  15. Zoëga B, Kärrholm J, Lind B (1998) Plate fixation adds stability to two-level anterior fusion in the cervical spine: a randomized study using radiostereometry. Eur Spine J 7:302–307

    Article  CAS  PubMed  Google Scholar 

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This study was supported with grants from: the Göteborg Medical Society; the Greta and Einar Askers Foundation; Bertha and Felix Neubergh’s Foundation and Gothenburg University.

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Correspondence to Björn Zoëga.

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Zoëga, B., Kärrholm, J. & Lind, B. Mobility provocation radiostereometry in anterior cervical spine fusions. Eur Spine J 12, 631–636 (2003).

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  • Anterior cervical fusion
  • Radiostereometry
  • Radiographs