Surgical Management of Basilar Invagination: Comparison of Clinical and Radiographic Outcomes Utilizing Differing Surgical Approaches
Yıl 2023,
, 330 - 338, 30.06.2023
Evren Sandal
,
Burak Kınalı
,
Ali Karadag
,
Sedat Çağlı
Öz
Aim: Previous studies have outlined various surgical approaches to treatment of basilar invagination, but none have compared multiple different treatment options using objective clinical and radiological criteria.
Material and Methods: We retrospectively reviewed the records of 30 patients with basilar invagination treated by five different surgical approaches. The surgical outcomes were evaluated and compared using objective clinical (Ranawat score) and radiological parameters (Chamberlain distance, atlantodental interval, and craniovertebral angle).
Results: Our results show a statistically significant improvement in the Ranawat score for patients undergoing 1) anterior decompression with posterior stabilization, 2) posterior decompression with posterior stabilization, and 3) the Goel procedure (posterior decompression, posterior reduction, cage distraction, and posterior stabilization). Of these, the Goel procedure produced the most significant improvement in functional and radiographic outcomes. Neither group without posterior stabilization (posterior decompression alone or endoscopic transnasal odontoidectomy alone) had a significant improvement in Ranawat score or radiographic outcomes.
Conclusion: For surgical management of basilar invagination, a combination of posterior decompression, posterior reduction, cage distraction, and posterior stabilization yielded the best clinical and radiological outcome. There is a risk of craniocervical instability and kyphosis and recurrence of stenosis in patients treated surgically without posterior stabilization. Therefore, when deciding on bacillary invagination surgery without posterior stabilization, it should be carefully considered.
Teşekkür
Dear Editorial Board,
On behalf of my co-authors, I am pleased to present for your consideration our original re-search article entitled “Surgical Management of Basilar Invagination: Comparison of Clinical and Radiographic Outcomes Utilizing Differing Surgical Approaches.” In this work, we attempt to shed light on the optimal approach for surgical treatment of basilar invagination by compar-ing functional and radiographic outcomes resulting from multiple commonly employed surgi-cal methods. We believe our exploratory study may help clarify debate on the management of these complex patients.
We have no conflicts of interest to disclose and no financial assistance was provided. No por-tion of this paper has been previously published or under consideration elsewhere.
Thank you for your consideration.
Sincerely,
Evren SANDAL
Kaynakça
- 1. Chamberlain WE. Basilar Impression (Platybasia): A Bizarre Developmental Anomaly of the Occipital Bone and Upper Cervical Spine with Striking and Misleading Neurologic Manifestations. Yale J Biol Med. 1939;11(5):487-496.
- 2. Goel A, Jain S, Shah A. Radiological Evaluation of 510 Cases of Basilar Invagination with Evidence of Atlantoaxial Instability (Group A Basilar Invagination). World Neurosurg. 2018;110:533-543.
- 3. MS. G. Neuroradiology. In: MS. G, ed. Handbook of Neurosurgery. NY: Thieme 2010:S126-144.
- 4. Goel A, Sathe P, Shah A. Atlantoaxial Fixation for Basilar Invagination without Obvious Atlantoaxial Instability (Group B Basilar Invagination): Outcome Analysis of 63 Surgically Treated Cases. World Neurosurg. 2017;99:164-170.
- 5. Joaquim AF, Ghizoni E, Giacomini LA, Tedeschi H, Patel AA. Basilar invagination: Surgical results. Journal of craniovertebral junction & spine. 2014;5(2):78-84.
- 6. GoelA,EllenbogenRG.,AbdulraufSI.,SekharLN.Craniovertebral Junction: A Reappraisal. In: Principles of Neurological Surgery. 3rd ed. Philadelphia: Elsevier Saunders; 2012:S471-486.
- 7. Hsu W, Wolinsky JP, Gokaslan ZL, Sciubba DM. Transoral approaches to the cervical spine. Neurosurgery. 2010;66(3 Suppl):119-125.
- 8. Menezes AH. VT, Albert GW. Developmental and Acquired Abnormalities of The Craniocervical Junction. In: Youman’s Neurological Surgery. Philadelphia: Elsevier Saunders; 2011:S2233-2244, S2962-2972.
- 9. al-Mefty O, Borba LA, Aoki N, Angtuaco E, Pait TG. The transcondylar approach to extradural nonneoplastic lesions of the craniovertebral junction. J Neurosurg. 1996;84(1):1-6.
- 10. Salas E, Sekhar LN, Ziyal IM, Caputy AJ, Wright DC. Variations of the extreme-lateral craniocervical approach: anatomical study and clinical analysis of 69 patients. J Neurosurg. 1999;90(2 Suppl):206-219.
- 11. Ture U, Pamir MN. Extreme lateral-transatlas approach for resection of the dens of the axis. J Neurosurg. 2002;96(1 Suppl):73-82.
- 12. Dasenbrock HH, Clarke MJ, Bydon A, et al. Endoscopic image- guided transcervical odontoidectomy: outcomes of 15 patients with basilar invagination. Neurosurgery. 2012;70(2):351-359; discussion 359-360.
- 13. Seker A, Inoue K, Osawa S, Akakin A, Kilic T, Rhoton AL, Jr. Comparison of endoscopic transnasal and transoral approaches to the craniovertebral junction. World Neurosurg. 2010;74(6):583-602.
- 14. Anderson PA, Oza AL, Puschak TJ, Sasso R. Biomechanics of occipitocervical fixation. Spine (Phila Pa 1976). 2006;31(7):755-761.
- 15. Goel A, Laheri V. Plate and screw fixation for atlanto-axial subluxation. Acta Neurochir (Wien). 1994;129(1-2):47-53.
- 16. Di Lorenzo N. Craniocervical junction malformation treated by transoral approach. A survey of 25 cases with emphasis on postoperative instability and outcome. Acta Neurochir (Wien). 1992;118(3-4):112-116.
- 17. Dickman CA, Crawford NR, Brantley AG, Sonntag VK. Biomechanical effects of transoral odontoidectomy. Neurosurgery. 1995;36(6):1146-1152; discussion 1152-1143.
- 18. Dickman CA, Locantro J, Fessler RG. The influence of transoral odontoid resection on stability of the craniovertebral junction. J Neurosurg. 1992;77(4):525-530.
- 19. Goel A, Bhatjiwale M, Desai K. Basilar invagination: a study based on 190 surgically treated patients. J Neurosurg. 1998;88(6):962-968.
- 20. Goel A. Progressive basilar invagination after transoral odontoidectomy: treatment by atlantoaxial facet distraction and craniovertebral realignment. Spine (Phila Pa 1976). 2005;30(18):E551-555.
- 21. Menezes AH, VanGilder JC, Graf CJ, McDonnell DE. Craniocervical abnormalities. A comprehensive surgical approach. J Neurosurg. 1980;53(4):444-455.
- 22. Menezes AH. Complications of surgery at the craniovertebral junction--avoidance and management. Pediatr Neurosurg. 1991;17(5):254-266.
- 23. Naderi S, Crawford NR, Melton MS, Sonntag VK, Dickman CA. Biomechanical analysis of cranial settling after transoral odontoidectomy. Neurosurg Focus. 1999;6(6):e7.
- 24. Zileli M, Cagli S. Combined anterior and posterior approach for managing basilar invagination associated with type I Chiari malformation. J Spinal Disord Tech. 2002;15(4):284-289.
- 25. Harkey HL, Crockard HA, Stevens JM, Smith R, Ransford AO. The operative management of basilar impression in osteogenesis imperfecta. Neurosurgery 1990;27:782-6
- 26. Bertrand J, Luc B, Philippe M, Philippe P. Anterior mandibular osteotomy for tumor extirpation: A critical evaluation. Head Neck 2000;22:323-7.
- 27. Magama S, Wakao N, Kitoh H, Matsuyama Y, Ishiguro N. Factors related to surgical outcome after posterior decompression and fusion for craniocervical junction lesions associated with osteogenesis imperfecta. Eur Spine J 2011;20 Suppl 2:S320-5.
- 28. Wei G, Shi C, Wang Z, Xia H, Yin Q, Wu Z. Surgical Outcome and Prognostic Analysis of Transoral Atlantoaxial Reduction Plate System for Basilar Invagination: A Voxel-Based Morphometry Study. J Bone Joint Surg Am. 2016 Oct 19;98(20):1729-1734. doi: 10.2106/JBJS.15.01151. PMID: 27869624.
- 29. Crockard HA, Sen CN.The transoral approach for the management of intradural lesions at the craniovertebral junction: review of 7 cases. Neurosurgery. 1991;28(1):88-97; discussion 97-88.
- 30. Botelho RV, Ferreira ED. Angular craniometry in craniocervical junction malformation. Neurosurg Rev. 2013;36(4):603-610; discussion 610.
- 31. Chandra PS, Kumar A, Chauhan A, Ansari A, Mishra NK, Sharma BS. Distraction, compression, and extension reduction of basilar invagination and atlantoaxial dislocation: a novel pilot technique. Neurosurgery. 2013;72(6):1040-1053; discussion 1053.
- 32. Goel A. Treatment of basilar invagination by atlantoaxial joint distraction and direct lateral mass fixation. J Neurosurg Spine. 2004;1(3):281-286.
- 33. Wajanavisit W, Lertudomphonwanit T, Fuangfa P, Chanplakorn P, Kraiwattanapong C, Jaovisidha S. Prevalence of High-Riding Vertebral Artery and Morphometry of C2 Pedicles Using a Novel Computed Tomography Reconstruction Technique. Asian Spine J. 2016;10(6):1141-1148.
- 34. Yeom JS, Buchowski JM, Kim HJ, Chang BS, Lee CK, Riew KD. Risk of vertebral artery injury: comparison between C1-C2 transarticular and C2 pedicle screws. Spine J. 2013;13(7):775-785.
- 35. Chandra PS, Prabhu M, Goyal N, Garg A, Chauhan A, Sharma BS. Distraction, Compression, Extension, and Reduction Combined With Joint Remodeling and Extra-articular Distraction: Description of 2 New Modifications for Its Application in Basilar Invagination and Atlantoaxial Dislocation: Prospective Study in
- 36. Guo SL, Zhou DB, Yu XG, Yin YH, Qiao GY. Posterior C1-C2 screw and rod instrument for reduction and fixation of basilar invagination with atlantoaxial dislocation. Eur Spine J. 2014;23(8):1666-1672.
- 37. Cobanoglu M, Bauer JM, Campbell JW, Shah SA.Basilar impression in osteogenesis imperfecta treated with staged halo traction and posterior decompression with short-segment fusion. J Craniovertebr Junction Spine. 2018 Jul-Sep;9(3):212-215. doi: 10.4103/jcvjs.JCVJS_63_18
- 38. Patel R, Solanki AM, Acharya A. Surgical outcomes of posterior occipito-cervical decompression and fusion for basilar invagination: A prospective study. J Clin Orthop Trauma. 2020 Nov 27;13:127-133. doi: 10.1016/j.jcot.2020.11.016. PMID: 33680811; PMCID: PMC7919955.
- 39. Claybrooks R, Kayanja M, Milks R, Benzel E. Atlantoaxial fusion: a biomechanical analysis of two C1-C2 fusion techniques. Spine J. 2007;7(6):682-688.
- 40. Harms J, Melcher RP. Posterior C1-C2 fusion with polyaxial screw and rod fixation. Spine (Phila Pa 1976). 2001;26(22):2467-2471.
- 41. Hartl R, Chamberlain RH, Fifield MS, Chou D, Sonntag VK, Crawford NR. Biomechanical comparison of two new atlantoaxial fixation techniques with C1-2 transarticular screw-graft fixation. J Neurosurg Spine. 2006;5(4):336-342.
- 42. Wang MY. Cervical crossing laminar screws: early clinical results and complications. Neurosurgery. 2007;61(5 Suppl 2):311-315; discussion 315-316.
- 43. Wright NM. Posterior C2 fixation using bilateral, crossing C2 laminar screws: case series and technical note. J Spinal Disord Tech. 2004;17(2):158-162.
- 44. Xia H, Yin Q, Ai F, et al. Treatment of basilar invagination with atlantoaxial dislocation: atlantoaxial joint distraction and fixation with transoral atlantoaxial reduction plate (TARP) without odontoidectomy. Eur Spine J. 2014;23(8):1648-1655.
- 45. Magerl F. SP. Stable posterior fusion of the atlas and axis by transarticular screw fixation. In: Cervical Spine. Austria: Springer Verlag; 1987:S322-327.
- 46. Menezes AH, VanGilder JC. Transoral-transpharyngeal approach to the anterior craniocervical junction. Ten-year experience with 72 patients. J Neurosurg. 1988;69(6):895-903.
- 47. Shah A, Goel A. Clival dysgenesis associated with Chiari Type 1 malformation and syringomyelia. J Clin Neurosci. 2010;17(3):400-401.
79 Cases. Neurosurgery. 2015;77(1):67-80; discussion 80.
Baziler İnvajinasyonun Cerrahi Tedavisi: Farklı Cerrahi Yaklaşımların Klinik ve Radyografik Sonuçların Karşılaştırılması
Yıl 2023,
, 330 - 338, 30.06.2023
Evren Sandal
,
Burak Kınalı
,
Ali Karadag
,
Sedat Çağlı
Öz
Amaç: Baziler invajinasyonun cerrahi tedavisine yönelik çeşitli yaklaşımların ana hatları literatürdeki birçok çalişmada araştırılmış ancak hiçbiri objektif klinik ve radyolojik kriterler kullanarak farklı tedavi seçeneklerini karşılaştırmamıştır. Çalışmamızda farklı cerrahi girişimle opera edilen baziller invaginasyonu olan hastaların objektif klinik ve radyolojik parametreler kullanılarak karşılaştırılması amaçlandı.
Yöntemler: 2000-2014 yılları arasında baziler invajinasyon nedeniyle opere edilen hastalar retrospektif olarak incelendi. Sekonder baziler invajinasyon kriterlerini karşılayan romatoid artritin neden olduğu atlantoaksiyal subluksasyonu olan iki olgu da çalışmaya dahil edildi. Çalışmaya beş farklı cerrahi yaklaşımla tedavi edilen baziler invajinasyonlu toplam 30 hasta dahil edildi. Cerrahi sonuçlar objektif klinik (Ranawat skoru) ve radyolojik parametreler (Chamberlain mesafesi, atlantodental interval ve kraniovertebral açı) kullanılarak değerlendirildi ve karşılaştırıldı.
Bulgular: Çalışmamızda posterior stabilizasyonlu anterior dekompresyon, posterior stabilizasyonlu posterior dekompresyon ve Goel prosedürü (posterior dekompresyon, posterior redüksiyon, kafes distraksiyonu ve posterior stabilizasyon) uygulanan hastalarda Ranawat skorunda istatistiksel olarak anlamlı bir iyileşme olduğu saptandı. Bunlardan Goel prosedürü fonksiyonel ve radyografik surveyde en iyi sonuçları gösterdi. Posterior stabilizasyonu uygulanmayan hiçbir grupta (tek başına posterior dekompresyon veya yalnızca endoskopik transnazal odontoidektomi), Ranawat skorunda veya radyografik sonuçlarda anlamlı bir iyileşme olmadı. Anterior dekompresyon ve posterior stabilizasyonun birlikte uygulandığı cerrahi prosedürlerde de başarı oranı yüksek idi.
Sonuç: Baziler invajinasyonun cerrahi tedavisinde posterior dekompresyon, posterior redüksiyon, kafes distraksiyonu ve posterior stabilizasyonun birlikte yapıldığı cerrahi uygulamalar en iyi klinik ve radyolojik sonucu verdi. Posterior stabilizasyonsuz cerrahi tedavi edilen hastalarda, kranioservikal instabilite ve kifoz gelişimi tekrar darlık oluşumu riskleri vardır. Bu nedenle posterior stabilizasyonsuz basiler invaginasyon ameliyatı kararı alınırken titizlikle düşünülmeli bu durumlar göz önünde bulundurulmalıdır.
Kaynakça
- 1. Chamberlain WE. Basilar Impression (Platybasia): A Bizarre Developmental Anomaly of the Occipital Bone and Upper Cervical Spine with Striking and Misleading Neurologic Manifestations. Yale J Biol Med. 1939;11(5):487-496.
- 2. Goel A, Jain S, Shah A. Radiological Evaluation of 510 Cases of Basilar Invagination with Evidence of Atlantoaxial Instability (Group A Basilar Invagination). World Neurosurg. 2018;110:533-543.
- 3. MS. G. Neuroradiology. In: MS. G, ed. Handbook of Neurosurgery. NY: Thieme 2010:S126-144.
- 4. Goel A, Sathe P, Shah A. Atlantoaxial Fixation for Basilar Invagination without Obvious Atlantoaxial Instability (Group B Basilar Invagination): Outcome Analysis of 63 Surgically Treated Cases. World Neurosurg. 2017;99:164-170.
- 5. Joaquim AF, Ghizoni E, Giacomini LA, Tedeschi H, Patel AA. Basilar invagination: Surgical results. Journal of craniovertebral junction & spine. 2014;5(2):78-84.
- 6. GoelA,EllenbogenRG.,AbdulraufSI.,SekharLN.Craniovertebral Junction: A Reappraisal. In: Principles of Neurological Surgery. 3rd ed. Philadelphia: Elsevier Saunders; 2012:S471-486.
- 7. Hsu W, Wolinsky JP, Gokaslan ZL, Sciubba DM. Transoral approaches to the cervical spine. Neurosurgery. 2010;66(3 Suppl):119-125.
- 8. Menezes AH. VT, Albert GW. Developmental and Acquired Abnormalities of The Craniocervical Junction. In: Youman’s Neurological Surgery. Philadelphia: Elsevier Saunders; 2011:S2233-2244, S2962-2972.
- 9. al-Mefty O, Borba LA, Aoki N, Angtuaco E, Pait TG. The transcondylar approach to extradural nonneoplastic lesions of the craniovertebral junction. J Neurosurg. 1996;84(1):1-6.
- 10. Salas E, Sekhar LN, Ziyal IM, Caputy AJ, Wright DC. Variations of the extreme-lateral craniocervical approach: anatomical study and clinical analysis of 69 patients. J Neurosurg. 1999;90(2 Suppl):206-219.
- 11. Ture U, Pamir MN. Extreme lateral-transatlas approach for resection of the dens of the axis. J Neurosurg. 2002;96(1 Suppl):73-82.
- 12. Dasenbrock HH, Clarke MJ, Bydon A, et al. Endoscopic image- guided transcervical odontoidectomy: outcomes of 15 patients with basilar invagination. Neurosurgery. 2012;70(2):351-359; discussion 359-360.
- 13. Seker A, Inoue K, Osawa S, Akakin A, Kilic T, Rhoton AL, Jr. Comparison of endoscopic transnasal and transoral approaches to the craniovertebral junction. World Neurosurg. 2010;74(6):583-602.
- 14. Anderson PA, Oza AL, Puschak TJ, Sasso R. Biomechanics of occipitocervical fixation. Spine (Phila Pa 1976). 2006;31(7):755-761.
- 15. Goel A, Laheri V. Plate and screw fixation for atlanto-axial subluxation. Acta Neurochir (Wien). 1994;129(1-2):47-53.
- 16. Di Lorenzo N. Craniocervical junction malformation treated by transoral approach. A survey of 25 cases with emphasis on postoperative instability and outcome. Acta Neurochir (Wien). 1992;118(3-4):112-116.
- 17. Dickman CA, Crawford NR, Brantley AG, Sonntag VK. Biomechanical effects of transoral odontoidectomy. Neurosurgery. 1995;36(6):1146-1152; discussion 1152-1143.
- 18. Dickman CA, Locantro J, Fessler RG. The influence of transoral odontoid resection on stability of the craniovertebral junction. J Neurosurg. 1992;77(4):525-530.
- 19. Goel A, Bhatjiwale M, Desai K. Basilar invagination: a study based on 190 surgically treated patients. J Neurosurg. 1998;88(6):962-968.
- 20. Goel A. Progressive basilar invagination after transoral odontoidectomy: treatment by atlantoaxial facet distraction and craniovertebral realignment. Spine (Phila Pa 1976). 2005;30(18):E551-555.
- 21. Menezes AH, VanGilder JC, Graf CJ, McDonnell DE. Craniocervical abnormalities. A comprehensive surgical approach. J Neurosurg. 1980;53(4):444-455.
- 22. Menezes AH. Complications of surgery at the craniovertebral junction--avoidance and management. Pediatr Neurosurg. 1991;17(5):254-266.
- 23. Naderi S, Crawford NR, Melton MS, Sonntag VK, Dickman CA. Biomechanical analysis of cranial settling after transoral odontoidectomy. Neurosurg Focus. 1999;6(6):e7.
- 24. Zileli M, Cagli S. Combined anterior and posterior approach for managing basilar invagination associated with type I Chiari malformation. J Spinal Disord Tech. 2002;15(4):284-289.
- 25. Harkey HL, Crockard HA, Stevens JM, Smith R, Ransford AO. The operative management of basilar impression in osteogenesis imperfecta. Neurosurgery 1990;27:782-6
- 26. Bertrand J, Luc B, Philippe M, Philippe P. Anterior mandibular osteotomy for tumor extirpation: A critical evaluation. Head Neck 2000;22:323-7.
- 27. Magama S, Wakao N, Kitoh H, Matsuyama Y, Ishiguro N. Factors related to surgical outcome after posterior decompression and fusion for craniocervical junction lesions associated with osteogenesis imperfecta. Eur Spine J 2011;20 Suppl 2:S320-5.
- 28. Wei G, Shi C, Wang Z, Xia H, Yin Q, Wu Z. Surgical Outcome and Prognostic Analysis of Transoral Atlantoaxial Reduction Plate System for Basilar Invagination: A Voxel-Based Morphometry Study. J Bone Joint Surg Am. 2016 Oct 19;98(20):1729-1734. doi: 10.2106/JBJS.15.01151. PMID: 27869624.
- 29. Crockard HA, Sen CN.The transoral approach for the management of intradural lesions at the craniovertebral junction: review of 7 cases. Neurosurgery. 1991;28(1):88-97; discussion 97-88.
- 30. Botelho RV, Ferreira ED. Angular craniometry in craniocervical junction malformation. Neurosurg Rev. 2013;36(4):603-610; discussion 610.
- 31. Chandra PS, Kumar A, Chauhan A, Ansari A, Mishra NK, Sharma BS. Distraction, compression, and extension reduction of basilar invagination and atlantoaxial dislocation: a novel pilot technique. Neurosurgery. 2013;72(6):1040-1053; discussion 1053.
- 32. Goel A. Treatment of basilar invagination by atlantoaxial joint distraction and direct lateral mass fixation. J Neurosurg Spine. 2004;1(3):281-286.
- 33. Wajanavisit W, Lertudomphonwanit T, Fuangfa P, Chanplakorn P, Kraiwattanapong C, Jaovisidha S. Prevalence of High-Riding Vertebral Artery and Morphometry of C2 Pedicles Using a Novel Computed Tomography Reconstruction Technique. Asian Spine J. 2016;10(6):1141-1148.
- 34. Yeom JS, Buchowski JM, Kim HJ, Chang BS, Lee CK, Riew KD. Risk of vertebral artery injury: comparison between C1-C2 transarticular and C2 pedicle screws. Spine J. 2013;13(7):775-785.
- 35. Chandra PS, Prabhu M, Goyal N, Garg A, Chauhan A, Sharma BS. Distraction, Compression, Extension, and Reduction Combined With Joint Remodeling and Extra-articular Distraction: Description of 2 New Modifications for Its Application in Basilar Invagination and Atlantoaxial Dislocation: Prospective Study in
- 36. Guo SL, Zhou DB, Yu XG, Yin YH, Qiao GY. Posterior C1-C2 screw and rod instrument for reduction and fixation of basilar invagination with atlantoaxial dislocation. Eur Spine J. 2014;23(8):1666-1672.
- 37. Cobanoglu M, Bauer JM, Campbell JW, Shah SA.Basilar impression in osteogenesis imperfecta treated with staged halo traction and posterior decompression with short-segment fusion. J Craniovertebr Junction Spine. 2018 Jul-Sep;9(3):212-215. doi: 10.4103/jcvjs.JCVJS_63_18
- 38. Patel R, Solanki AM, Acharya A. Surgical outcomes of posterior occipito-cervical decompression and fusion for basilar invagination: A prospective study. J Clin Orthop Trauma. 2020 Nov 27;13:127-133. doi: 10.1016/j.jcot.2020.11.016. PMID: 33680811; PMCID: PMC7919955.
- 39. Claybrooks R, Kayanja M, Milks R, Benzel E. Atlantoaxial fusion: a biomechanical analysis of two C1-C2 fusion techniques. Spine J. 2007;7(6):682-688.
- 40. Harms J, Melcher RP. Posterior C1-C2 fusion with polyaxial screw and rod fixation. Spine (Phila Pa 1976). 2001;26(22):2467-2471.
- 41. Hartl R, Chamberlain RH, Fifield MS, Chou D, Sonntag VK, Crawford NR. Biomechanical comparison of two new atlantoaxial fixation techniques with C1-2 transarticular screw-graft fixation. J Neurosurg Spine. 2006;5(4):336-342.
- 42. Wang MY. Cervical crossing laminar screws: early clinical results and complications. Neurosurgery. 2007;61(5 Suppl 2):311-315; discussion 315-316.
- 43. Wright NM. Posterior C2 fixation using bilateral, crossing C2 laminar screws: case series and technical note. J Spinal Disord Tech. 2004;17(2):158-162.
- 44. Xia H, Yin Q, Ai F, et al. Treatment of basilar invagination with atlantoaxial dislocation: atlantoaxial joint distraction and fixation with transoral atlantoaxial reduction plate (TARP) without odontoidectomy. Eur Spine J. 2014;23(8):1648-1655.
- 45. Magerl F. SP. Stable posterior fusion of the atlas and axis by transarticular screw fixation. In: Cervical Spine. Austria: Springer Verlag; 1987:S322-327.
- 46. Menezes AH, VanGilder JC. Transoral-transpharyngeal approach to the anterior craniocervical junction. Ten-year experience with 72 patients. J Neurosurg. 1988;69(6):895-903.
- 47. Shah A, Goel A. Clival dysgenesis associated with Chiari Type 1 malformation and syringomyelia. J Clin Neurosci. 2010;17(3):400-401.
79 Cases. Neurosurgery. 2015;77(1):67-80; discussion 80.