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European Spine Journal

, Volume 18, Issue 8, pp 1135–1153 | Cite as

C2-fractures: part II. A morphometrical analysis of computerized atlantoaxial motion, anatomical alignment and related clinical outcomes

  • Heiko KollerEmail author
  • Frank Acosta
  • Rosemarie Forstner
  • Juliane Zenner
  • Herbert Resch
  • Mark Tauber
  • Stefan Lederer
  • Alexander Auffarth
  • Wolfgang Hitzl
Original Article

Abstract

Knowledge on the outcome of C2-fractures is founded on heterogenous samples with cross-sectional outcome assessment focusing on union rates, complications and technical concerns related to surgical treatment. Reproducible clinical and functional outcome assessments are scant. Validated generic and disease specific outcome measures were rarely applied. Therefore, the aim of the current study is to investigate the radiographic, functional and clinical outcome of a patient sample with C2-fractures. Out of a consecutive series of 121 patients with C2 fractures, 44 met strict inclusion criteria and 35 patients with C2-fractures treated either nonsurgically or surgically with motion-preserving techniques were surveyed. Outcome analysis included validated measures (SF-36, NPDI, CSOQ), and a functional CT-scanning protocol for the evaluation of C1–2 rotation and alignment. Mean follow-up was 64 months and mean age of patients was 52 years. Classification of C2-fractures at injury was performed using a detailed morphological description: 24 patients had odontoid fractures type II or III, 18 patients had fracture patterns involving the vertebral body and 11 included a dislocated or a burst lateral mass fracture. Thirty-one percent of patients were treated with a halo, 34% with a Philadelphia collar and 34% had anterior odontoid screw fixation. At follow-up mean atlantoaxial rotation in left and right head position was 20.2° and 20.6°, respectively. According to the classification system of posttreatment C2-alignment established by our group in part I of the C2-fracture study project, mean malunion score was 2.8 points. In 49% of patients the fractures healed in anatomical shape or with mild malalignment. In 51% fractures healed with moderate or severe malalignment. Self-rated outcome was excellent or good in 65% of patients and moderate or poor in 35%. The raw data of varying nuances allow for comparison in future benchmark studies and metaanalysis. Detailed investigation of C2-fracture morphology, posttreatment C2-alignment and atlantoaxial rotation allowed a unique outcome analysis that focused on the identification of risk factors for poor outcome and the interdependencies of outcome variables that should be addressed in studies on C2-fractures. We recognized that reduced rotation of C1–2 per se was not a concern for the patients. However, patients with worse clinical outcomes had reduced total neck rotation and rotation C1–2. In turn, C2-fractures, especially fractures affecting the lateral mass that healed with atlantoaxial deformity and malunion, had higher incidence of atlantoaxial degeneration and osteoarthritis. Patients with increased severity of C2-malunion and new onset atlantoaxial arthritis had worse clinical outcomes and significantly reduced rotation C1–2. The current study offers detailed insight into the radiographical, functional and clinical outcome of C2-fractures. It significantly adds to the understanding of C2-fractures.

Keywords

Cervical spine Atlantoaxial motion C2-fracture Clinical outcome Functional outcome 

Supplementary material

586_2009_901_MOESM1_ESM.doc (648 kb)
The analysis of the instantaneous center of rotation (ICR) of C1-C2 following C2-fractures. (DOC 648 kb)
586_2009_901_MOESM2_ESM.doc (132 kb)
Supplementary Table 1 (DOC 132 kb)
586_2009_901_MOESM3_ESM.doc (134 kb)
Supplementary Tables 2, 3 and 10 (DOC 134 kb)
586_2009_901_MOESM4_ESM.doc (54 kb)
Supplementary Table 9 (DOC 54 kb)

References

  1. 1.
    Aebi M, Etter C, Coscia M et al (1989) Fractures of the odontoid process: treatment with anterior screw fixation. Spine 14:1066–1070. doi: 10.1097/00007632-198910000-00007 CrossRefGoogle Scholar
  2. 2.
    Apfelbaum RI, Lonser RR, Veres R, Casez A (2000) Direct anterior screw fixation for recent and remote odontoid fractures. J Neurosurg (Spine 2) 93:227–236CrossRefGoogle Scholar
  3. 3.
    Bazaz R, Lee MJ, Yoo JU (2002) Incidence of dysphagia after anterior cervical spine surgery: a prospective study. Spine 27:2453–2458. doi: 10.1097/00007632-200211150-00007 PubMedCrossRefGoogle Scholar
  4. 4.
    BenDebba M, Heller J, Ducker TB, Eisinger JM (2002) Cervical spine outcomes questionnaire. Its development and psychometric properties. Spine 27:2116–2124. doi: 10.1097/00007632-200210010-00007 PubMedCrossRefGoogle Scholar
  5. 5.
    Benzel EC, Hart BL, Ball PA, Baldwin NG, Orrison WW, Espinosa M (1994) Fractures of the C2-vertebral body. J Neurosurg 81:206–212PubMedCrossRefGoogle Scholar
  6. 6.
    Bilge O (2004) An anatomic and morphometric study of C2 nerve root ganglion and its corresponding foramen. Spine 29:495–499. doi: 10.1097/01.BRS.0000113872.18219.7B PubMedCrossRefGoogle Scholar
  7. 7.
    Blauth M, Richter M, Lange U (1999) Transarticular screw fixation C1/C2 in traumatic atlantoaxial instabilities. Comparison between percutaneous and open procedures. Orthopade 28:651–661PubMedGoogle Scholar
  8. 8.
    Bogduk N, Mercer S (2000) Biomechanics of the cervical spine. I: normal kinematics. Clin Biomech (Bristol, Avon) 15:633–648. doi: 10.1016/S0268-0033(00)00034-6 CrossRefGoogle Scholar
  9. 9.
    Castro WH, Sautmann A, Schilgen M, Sautmann M (2000) Noninvasive three-dimensional analysis of cervical spine motion in normal subjects in relation to age and sex. An experimental examination. Spine 25:443–449. doi: 10.1097/00007632-200002150-00009 PubMedCrossRefGoogle Scholar
  10. 10.
    Chang K, Liu Y, Cheng P (1994) One Herbert double-threaded compression screw fixation of displaced type II odontoid fractures. J Spinal Disord 71:62–69CrossRefGoogle Scholar
  11. 11.
    Chiba K, Fujimura Y, Toyama Y, Takahata T, Nakanishi T, Hirabayashi K (1993) Anterior screw fixation for odontoid fracture: clinical results in 45 cases. Eur Spine J 2:76–81. doi: 10.1007/BF00302707 CrossRefPubMedGoogle Scholar
  12. 12.
    Clark CR, White AA (1985) Fractures of the dens: A multicenter study. J Bone Joint Surg 67-A:1340–1348Google Scholar
  13. 13.
    Dai LY, Yuan W, Ni N, Liu HK, Jia LS, Zhao DL, Xu YK (2000) Surgical treatment of non-united fractures of the odontoid process, with special reference to occipitocervical fusion for unreducible atlantoaxial subluxation or instability. Eur Spine J 9:118–122. doi: 10.1007/s005860050221 PubMedCrossRefGoogle Scholar
  14. 14.
    Dreyfuss P, Michaelsen M, Fletcher D (1994) Atlanto-occipital and lateral atlanto-axial joint pain patterns. Spine 19:1125–1131PubMedCrossRefGoogle Scholar
  15. 15.
    Dumas JL, Thoreux P, Attali P, Goldlust D, Chevrel JP (1994) Three-dimensional CT analysis of atlantoaxial rotation: results in the normal subject. Surg Radiol Anat 16:199–204PubMedCrossRefGoogle Scholar
  16. 16.
    Dvorak J, Penning L, Hayek J, Panjabi MM, Grob D, Zehnder R (1988) Functional diagnostics of the cervical spine using computer tomography. Neurorad 30:132–137. doi: 10.1007/BF00395614 CrossRefGoogle Scholar
  17. 17.
    Dvorak MF, Fisher CG, Aarabi B, Harris MB, Hurbert J, Rampersaud R, Vaccaro A, Harrop JS, Nockerls RP, Madrazo IN, Schwartz D, Kwon BK, Zhao Y, Fehlings MG (2007) Clinical outcomes of 90 isolated unilateral facet fractures, subluxations, and dislocations treated surgically and nonoperatively. Spine 32:3007–3031PubMedCrossRefGoogle Scholar
  18. 18.
    Dvorak MF, Johnson MG, Boyd M, Johnson G, Kwon BK, Fisher CG (2005) Long-term health-related quality of life outcomes following Jefferson-type burst fractures of the atlas. J Neurosurg Spine 2:411–417PubMedCrossRefGoogle Scholar
  19. 19.
    Dvorak MF Johnston M, Pitzen T (2002) The radiographic failure of single segment anterior cervical plate fixation in traumatic cervical flexion/distraction injuries. Presented at Canadian Spine Society 2nd Annual Meeting. Vernon, British Columbia, CanadaGoogle Scholar
  20. 20.
    Ehni G, Benner N (1984) Occipital neuralgia and the C1–2 arthrosis syndrome. J Neurosurg 61:961–965PubMedCrossRefGoogle Scholar
  21. 21.
    Ferrer S (2001) Letter to the editor. Spine 26:158–159Google Scholar
  22. 22.
    Finn M, Fassett DR, Apfelbaum RI (2007) Surgical treatment of nonrheumatoid atlantoaxial degenerative arthtiris producing pain and myelopathy. Spine 32:3067–3073PubMedCrossRefGoogle Scholar
  23. 23.
    Fisher CG, Dvorak MFS, Leith J, Wing PC (2002) Comparison of outcomes for unstable lower cervical flexion teardrop fractures managed with halo thoracic vest versus anterior corpectomy and plating. Spine 27:160–166. doi: 10.1097/00007632-200201150-00008 PubMedCrossRefGoogle Scholar
  24. 24.
    Fisher CG, Noonan VK, Dvorak MF (2006) Changing face of spine trauma care in North America. Spine 31(Suppl):S2–S8. doi: 10.1097/01.brs.0000217948.02567.3a PubMedCrossRefGoogle Scholar
  25. 25.
    Fountas KN, Kapsalaki EZ, Karampelas I, Feltes CH, Dimopoulos VG, Machinis TG, Nikolakakos LG, Boev AN, Choudhri H, Smisson HF, Robinson JS Jr (2005) Results of long-term follow-up in patients undergoing anterior odontoid screw fixation for type II and rostral type III odontoid fractures. Spine 30:661–669. doi: 10.1097/01.brs.0000155415.89974.d3 PubMedCrossRefGoogle Scholar
  26. 26.
    Fujimura Y, Nishi Y, Koyabashi K (1996) Classification and treatment of axis body fractures. J Orthop Trauma 10:536–540. doi: 10.1097/00005131-199611000-00005 PubMedCrossRefGoogle Scholar
  27. 27.
    German JW, Hart BL, Benzel EC (2005) Nonoperative management of verticla C2 body fractures. Neurosurg 56:516–520. doi: 10.1227/01.NEU.0000153908.53579.E4 CrossRefGoogle Scholar
  28. 28.
    Ghanayem AJ, Leventhal M, Bohlman HH (1996) Osteoarthrosis of the atlantoaxial joints. Long-term follow-up after treatment with arthrodesis. J Bone Joint Surg 78-A:1300–1307Google Scholar
  29. 29.
    Grauer JN, Shafi B, Hilibrand AS, Harrop JS, Kwon BK, Beiner JM, Albert TJ, Fehlings MG, Vaccaro AR (2005) Proposal of a modified, treatment-oriented classification of odontoid fractures. Spine J 5:123–129. doi: 10.1016/j.spinee.2004.09.014 PubMedCrossRefGoogle Scholar
  30. 30.
    Greene KA, Dickmann CA, Marciano FF, Drabier JB, Hadley MN, Sonntag VK (1997) Acute axis fractures: analysis of management and outcome in 340 consequitive cases. Spine 22:1843–1852. doi: 10.1097/00007632-199708150-00009 PubMedCrossRefGoogle Scholar
  31. 31.
    Grob D, Bremerich FH, Dvorak J, Mannion AF (2006) Transarticular screw fixation for osteoarthritis of the atlantoaxial segment. Eur Spine J 15:283–291. doi: 10.1007/s00586-005-0963-x PubMedCrossRefGoogle Scholar
  32. 32.
    Gunnarsson T, Massicotte EM, Govender PV, Rampersaud YR, Fehlings MG (2007) The use of C1 lateral mass screws in complex cervical spine surgery: indications, techniques, and outcome in a prospective consecutive series of 25 cases. J Spinal Disord Tech 20:308–316. doi: 10.1097/01.bsd.0000211291.21766.4d PubMedCrossRefGoogle Scholar
  33. 33.
    Hähnle U, Wiesniewski TF, Craig JB (1999) Shear fracture through the body of the axis vertebra. Spine 24:2278–2281. doi: 10.1097/00007632-199911010-00018 PubMedCrossRefGoogle Scholar
  34. 34.
    Heller JG, Levz MJ, Barrow DL (1993) Odontoid fracture malunion with fixed atlantoaxial subluxation. Spine 18:311–314. doi: 10.1097/00007632-199302000-00024 PubMedCrossRefGoogle Scholar
  35. 35.
    Holly LT, Batzdorf U, Foley KT (2000) Treatment of severe retromastoid pain secondary to C1–2 arthrosis by using cervical fusion. J Neurosurg (Spine 2) 92:162–168CrossRefGoogle Scholar
  36. 36.
    Hollz LT, Batzdorf U, Foley KT (2000) Treatment of severe retromastoid pain secondary to C1–2 arthrosis by using cervical fusion. J Neurosurg (Spine 2) 92:162–168CrossRefGoogle Scholar
  37. 37.
    Ishii K, Chiba K, Maruiwa H, Nakamura M, Matsumotot M, Toyama Y (2006) Pathognomic radiological signs for predicting prognosis in patients with chronic atlantoaxial rotatory fixation. J Neurosurg Spine 5:385–391. doi: 10.3171/spi.2006.5.5.385 PubMedCrossRefGoogle Scholar
  38. 38.
    Javid D, Hedlund R, Vavruch L, Leszniewski W (2001) Is the efficacy of the cloward procedure overestimated? Technique of evaluation affects the outcome. Eur Spine J 10:222–227. doi: 10.1007/s005860100261 PubMedCrossRefGoogle Scholar
  39. 39.
    Jeanneret B, Vernet O, Frei S, Magerl F (1991) Atlantoaxial mobility after screw fixation of the odontoid: a computer tomographic study. J Spinal Disord Tech 4:203–211. doi: 10.1097/00002517-199106000-00011 CrossRefGoogle Scholar
  40. 40.
    Jeanneret B, Magerl M (1985) Klinische Analyse der Spätresultate nach Hangman-Frakturen. Z Orthop 123:721Google Scholar
  41. 41.
    Julien TD, Frankel B, Traynelis VC, Ryken TC (2000) Evidence based analysis of odontoid fracture management. Neurosurg Focus 8(6):1–6CrossRefGoogle Scholar
  42. 42.
    Kim YS, Lee YK, Moon SJ, Kim SH (2007) Post-traumatic atlantoaxial rotatory fixation in an adult: a case report. Spine 32:E682–E687. doi: 10.1097/BRS.0b013e318074c3ce PubMedCrossRefGoogle Scholar
  43. 43.
    Koivikko MP, Kiuru MJ, Koskinen SK, Myllynen P, Santavirta S, Kivisaari L (2004) Factors associated with nonunion in conservatively treated type-II fractures of the odontoid process. J Bone Joint Surg 86-B:1146–1151. doi: 10.1302/0301-620X.86B8.14839 CrossRefGoogle Scholar
  44. 44.
    Koller H, Acosta F, Tauber M, Komarek E, Fox M, Moursy M, Hitzl W (2009) C2-fractures: part I. Quantitative morphology of the C2 vertebra is a prerequisite for the radiographic assessment of posttraumatic C2-alignment and the investigation of clinical outcomes. Eur Spine J. doi: 10.1007/s00586-009-0900-5
  45. 45.
    Koller H, Assuncao A, Kammermeier V, Holz U (2006) Simulateous anterior arthrodesis C2–3 and anterior odontoid screw fixation for stabilization of a 4-part fracture of the axis—a technical description. J Spinal Disord Tech 19:362–367. doi: 10.1097/01.bsd.0000204502.99471.9a PubMedCrossRefGoogle Scholar
  46. 46.
    Koller H, Daniaux H, Gruber H, Blauth M, Kathrein A (2006) The unstable traumatic spondylolisthesis C2–3. Akt Traumatol 35:183–202. doi: 10.1055/s-2005-865960 CrossRefGoogle Scholar
  47. 47.
    Koller H, Kammermeier V, Assuncao A, Holz U (2007) Spinal stenosis C1–2 following redo surgery for failed odontoid screw fixation—scrutinizing the odontoid fracture classification. Internet J Spine Surg 3:1–11Google Scholar
  48. 48.
    Koller H, Kathrein A (2006) Letter to the editor concerning: a systematic review of the management of hangman’s fractures by Xin-Feng Li et al. (2006) Eur Spine J 15:257–269. Eur Spine J 15:257–269. doi: 10.1007/s00586-005-0918-2 CrossRefGoogle Scholar
  49. 49.
    Koller H, Tauber M, Kathrein A (2007) Letter to the editor. Spine 32:1571–1572. doi: 10.1097/BRS.0b013e318068660c CrossRefGoogle Scholar
  50. 50.
    Koller H, Reynolds J, Zenner J, Forstner R, Hempfing A, Maislinger I, Kolb K, Tauber M, Resch H, Hitzl W (2009) Mid- to long-term outcome of instrumented anterior cervical fusion for subaxial injuries. Eur Spine J. doi: 10.1007/s00586-008-0879-3
  51. 51.
    Koller H, Kammermeier V, Ulbricht D, Assuncao A, Karolus S, van den Berg B, Holz U (2006) Anterior retropharyngeal fixation C1–2 for stabilization of atlantoaxial instabilities: study of feasibility, technical descriotion and preliminary results. Eur Spine J 15:1326–1338. doi: 10.1007/s00586-006-0103-2 PubMedCrossRefGoogle Scholar
  52. 52.
    Korres DS, Papagelopoulos PJ, Mavrogenis AF, Sapkas GS, Patsinevelos A, Kyriazopoulos P, Evangelopoulos D (2004) Multiple fractures of the axis. Orthopedics 27:1096–1099PubMedGoogle Scholar
  53. 53.
    Kwon BK, Fisher CG, Boyd MC, Cobb J, Jebson VN, Wing P, Dvorak MF (2007) A prospective randomized controlled trial of anterior compared with posterior stabilization for unilateral facet injuries of the cervical spine. J Neurosurg Spine 7:1–12. doi: 10.3171/SPI-07/07/001 PubMedCrossRefGoogle Scholar
  54. 54.
    Lakshmanan P, Jones A, Howes J, Lyons K (2005) CT evalutation of the pattern of odontoid fractures in the elderly-relationship to upper cervical spine osteoarthrosis. Eur Spine J 14:78–83. doi: 10.1007/s00586-004-0743-z PubMedCrossRefGoogle Scholar
  55. 55.
    Liu G, Buchowski JM, Shen H, Yeom JS, Riew D (2008) The feasibility of microscope-assisted ‘free-hand’ C1 lateral mass screw insertion without fluoroscopy. Spine 33:1042–1049. doi: 10.1097/BRS.0b013e31816d72b5 PubMedCrossRefGoogle Scholar
  56. 56.
    Maak TG, Grauer JN (2006) The contemporary treatment of odontoid injuries. Spine 31:S53–S60. doi: 10.1097/01.brs.0000217941.55817.52 PubMedCrossRefGoogle Scholar
  57. 57.
    Müller EJ, Wick M, Russe OJ, Palta M, Muhr G (2000) Anterior screw fixation for odontoid fractures (in german). Unfallch 103:38–43. doi: 10.1007/s001130050006 CrossRefGoogle Scholar
  58. 58.
    Pang D, Li Veetai (2004) Atlantoaxial rotatory fixation: part 1—biomechanics of normal rotation at the atlantoaxial joint in children. Neurosurg 55:614–625. doi: 10.1227/01.NEU.0000134386.31806.A6 CrossRefGoogle Scholar
  59. 59.
    Pang D, Veetai Li (2005) Atlantoaxial rotatory fixation: part 2—new diagnostic paradigm and a new classification based on motion analysis using computed tomographic imaging. Neurosurg 57:941–953. doi: 10.1227/01.NEU.0000181309.13211.3A CrossRefGoogle Scholar
  60. 60.
    Pang D, Veetai Li (2005) Atlantoaxial rotatory fixation: part 3—a prospective study of the clinical manifestation, diagnosis, management, and outcome of children with atlantoaxial rotatory fixation. Neurosurg 57:954–972. doi: 10.1227/01.NEU.0000180052.81699.81 CrossRefGoogle Scholar
  61. 61.
    Penning L, Wilmink JT (1987) Rotation of the cervical spine. A CT study in normal subjects. Spine 12:732–738. doi: 10.1097/00007632-198710000-00003 PubMedCrossRefGoogle Scholar
  62. 62.
    Platzer P, Thalhammer G, Ostermann R, Wieland T, Vecsei V, Gaebler C (2007) Anterior screw fixation of odontoid fractures comparing younger and elderly patients. Spine 32:1714–1720. doi: 10.1097/BRS.0b013e3180dc9758 PubMedCrossRefGoogle Scholar
  63. 63.
    Platzer P, Thalhammer G, Sarahrudi K, Kovar F, Vekszler G, Vécsei V, Gaebler C (2007) Nonoperative management of odontoid fractures using a halo-thoracic vest. Neurosurg 61:529–530CrossRefGoogle Scholar
  64. 64.
    Roche CJ, King SJ, Dangerfield PH, Carty HM (2002) The atlanto-axial joint: physiological range mof rotation on MRI and CT. Clin Radiol 57:103–108. doi: 10.1053/crad.2001.0703 PubMedCrossRefGoogle Scholar
  65. 65.
    Ruf M, Melcher R, Harms J (2003) Transoral reduction and osteosynthesis C1 as a function-preserving option in the treatment of unstable Jefferson fractures. Spine 29:823–827. doi: 10.1097/01.BRS.0000116984.42466.7E CrossRefGoogle Scholar
  66. 66.
    Schaeren S, Jeanneret B (2005) Atlantoaxial osteoarthritis: case series and review of literature. Eur Spine J 14:501–506. doi: 10.1007/s00586-004-0856-4 PubMedCrossRefGoogle Scholar
  67. 67.
    Seelig M, Roth R, Worsdorfer O, Keerl R (2000) Transoral correction osteotomy in transdental fracture dislocation that healed in the wrong position. Unfallch 103:791–794. doi: 10.1007/s001130050619 CrossRefGoogle Scholar
  68. 68.
    Seybold EA, Bayley JC (1998) Functional outcome of surgically and conservativly managed dens fractures. Spine 23:1837–1846. doi: 10.1097/00007632-199809010-00006 PubMedCrossRefGoogle Scholar
  69. 69.
    Sgambati E, Capaccioli L, Biagiotti R, Giurovich E, Montigiani L, Brizzi E (1998) Anatomical-radiological and morphometric analysis of the lateral atlantoaxial joint. Ital J Anat Embryol 103:117–123PubMedGoogle Scholar
  70. 70.
    Signoret F, Feron JM, Bonfait H, Patel A (1986) Fractured odontoid with fractured superior articular process of the axus. J Bone Joint Surg 68-B:182–184Google Scholar
  71. 71.
    Stulik J, Vyskocil T, Sebesta P, Kryl J (2006) Atlantoaxial fixation using the polyaxial screw-rod system. Eur Spine J (Epub)Google Scholar
  72. 72.
    Subach BR, Morone MA, Haid RW, McLaughlin MR, Rodts GR, Comey CH (1999) Management of acute odontoid fractures with single-screw anterior fixation. Neurosurg 45:812–820. doi: 10.1097/00006123-199910000-00015 CrossRefGoogle Scholar
  73. 73.
    Sugimoto Y, Tanaka M, Nakanishi K, Misawa H, Takigawa T, Ozaki T (2007) Assessing the range of cervical rotation in patients with rheumatoid arthritis after atlantoaxial screw fixation using axial CT. Spine 32:2318–2321PubMedCrossRefGoogle Scholar
  74. 74.
    Tuite GF, Papadopoulos SM, Sonntag VK (1992) Caspar plate fixation for treatment of complex hangman’s fracture. Neurosurg 30:3761–3764CrossRefGoogle Scholar
  75. 75.
    Venon H, Mior S (1991) The neck disability index: a study of reliability and validity. J Manipulative Physiol Ther 14:409–419Google Scholar
  76. 76.
    Verheggen R, Jansen J (1994) Fractures of the odontoid process: analysis of the functional results after surgery. Eur Spine J 3:146–150PubMedCrossRefGoogle Scholar
  77. 77.
    Vernon H, Mior S (1991) The neck disability index: a study of reliability and validity. J Manipulative Physiol Ther 14:409–419PubMedGoogle Scholar
  78. 78.
    Wang C, Yan M, Zhou H, Wang S, Dang G (2007) Atlantoaxial transarticular screw fixation with morselized autograft and without additional internal fixation. Spine 32:643–646. doi: 10.1097/01.brs.0000257539.75693.cc PubMedCrossRefGoogle Scholar
  79. 79.
    Wang C, Zan M, Yhou HT, Wang SL, Dang GT (2006) Open reduction of irreducible atlantoaxial dislocation by transoral anterior atlantoaxial release and posterior internal fixation. Spine 31:E30–E313Google Scholar
  80. 80.
    Ware JE Jr (2000) SF-36 health survey update. Spine 25:3130–3139. doi: 10.1097/00007632-200012150-00008 PubMedCrossRefGoogle Scholar
  81. 81.
    White AA, Panjabi MM (1978) Kinematics of the spine. In: White AA, Panjabi MM (eds) Clinical biomechanics of the spine. JB Lippincott, Philadelphia, pp 87–125Google Scholar
  82. 82.
    Whitesides TE, McDonald AP (1978) Lateral retroparyngeal approach to the upper cervical spine. Orthop Clin North Am 9:1115–1127PubMedGoogle Scholar
  83. 83.
    Ying Z, Wen Y, Xinwei W, Yong T, Hongyu L, Zhu H, Qinggang Z, Weihong Z, Yonggeng C (2008) Anterior cervical discectomy and fusion for unstable traumatic spondylolisthesiss of the axis. Spine 33:255–258PubMedCrossRefGoogle Scholar
  84. 84.
    Zapletal J, de Valois JC (1997) Radiographic prevalance of advanced lateral C1–C2 osteoarthritis. Spine 22:2511–2513. doi: 10.1097/00007632-199711010-00009 PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Heiko Koller
    • 1
    Email author
  • Frank Acosta
    • 2
  • Rosemarie Forstner
    • 3
  • Juliane Zenner
    • 4
  • Herbert Resch
    • 1
  • Mark Tauber
    • 1
  • Stefan Lederer
    • 1
  • Alexander Auffarth
    • 1
  • Wolfgang Hitzl
    • 5
  1. 1.Department for Traumatology and Sports InjuriesParacelsus Medical UniversitySalzburgAustria
  2. 2.Department of Neurological SurgeryUniversity of CaliforniaSan FranciscoUSA
  3. 3.Institute for RadiodiagnosticsParacelsus Medical UniversitySalzburgAustria
  4. 4.German Scoliosis CenterWerner Wicker ClinicBad WildungenGermany
  5. 5.Research Office, BiostatisticsParacelsus Medical UniversitySalzburgAustria

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