- Email: [email protected]
Use of Cervical Disk Arthroplasty to Treat Noncontiguous Cervical Disk Herniations
Journal Pre-proof Use of Cervical Disc Arthroplasty to Treat Non-Contiguous Cervical Disc Herniations: A Case Report G. Damian Brusko, BS, Evan Luther, MD, Allan D. Levi, MD, PhD PII:
S1878-8750(19)32634-8
DOI:
https://doi.org/10.1016/j.wneu.2019.10.019
Reference:
WNEU 13490
To appear in:
World Neurosurgery
Received Date: 31 July 2019 Revised Date:
1 October 2019
Accepted Date: 3 October 2019
Please cite this article as: Brusko GD, Luther E, Levi AD, Use of Cervical Disc Arthroplasty to Treat Non-Contiguous Cervical Disc Herniations: A Case Report, World Neurosurgery (2019), doi: https:// doi.org/10.1016/j.wneu.2019.10.019. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Elsevier Inc. All rights reserved.
Non-Contiguous Cervical Artificial Disc 1 Use of Cervical Disc Arthroplasty to Treat Non-Contiguous Cervical Disc Herniations: A Case Report G. Damian Brusko, BS,1 Evan Luther, MD,1 and Allan D. Levi, MD, PhD1 1
Department of Neurological Surgery
University of Miami Miller School of Medicine Lois Pope Life Center 1095 NW 14th Terrace Miami, Florida, U.S.A 33136
Corresponding author: G. Damian Brusko Lois Pope Life Center Department of Neurological Surgery 1095 NW 14th Terrace Miami, FL 33136 Tel.: (305) 243-3294 Fax: (305) 243-3337 Email: [email protected]
Keywords: Arthroplasty, Bryan Disc, Cervical, Disc Herniation, Fusion, Multi-Level
Running Head: Non-Contiguous Cervical Artificial Disc
Non-Contiguous Cervical Artificial Disc 1 Abstract Background Cervical disc arthroplasty (CDA) is now a widely accepted alternative to anterior cervical interbody fusion, which is known to reduce normal cervical motion and increase the incidence of adjacent segment disease. Although multiple studies report the use of cervical disc arthroplasty to treat multi-level cervical disease, this is the first report in the literature detailing the placement of multiple, non-contiguous artificial discs. Case Description We describe a 41-year-old male who presented with myelopathy and left upper extremity radiculopathy resulting from two cervical disc herniations separated by a normal intervening level. He underwent an anterior cervical discectomy and placement of an artificial disc prosthesis at cervical (C) 4-5 and C6-7 while leaving C5-6 intact. Conclusion This approach serves to preserve cervical motion, spinal stability, and lordosis across all three levels, thus demonstrating that it is a viable alternative to a multi-level anterior cervical interbody fusion.
Non-Contiguous Cervical Artificial Disc 2 Background Cervical disc arthroplasty (CDA) is a widely accepted alternative to anterior cervical interbody fusion, which is known to reduce cervical motion and increase the incidence of adjacent segment disease (ASD).1 In a randomized, controlled clinical trial with an artificial disc prosthesis, CDA demonstrated improved outcomes related to segment motion, reoperation at adjacent segments, and neck pain.2 To treat contiguous multi-level disease, the CDA has been increasingly employed since the first reported case in 2003.3 Previous reports have mentioned the use of CDA to treat multilevel non-contiguous cervical spondylosis but analysis of these patients and long-term outcomes still remain limited.4 Thus, no published studies to date describe placement of two artificial discs at non-adjacent cervical levels with subsequent patient followup. We present a case of a 41-year-old male with disc herniations at C4-5 and C6-7 who underwent two-level anterior decompression with placement of an artificial disc at each affected level.
Case Description Clinical Presentation A 41-year old male presented with a two-month history of severe neck pain radiating down the left arm, primarily into the shoulder. Initial computed tomography (CT) scan demonstrated a C4-5 disc extrusion and a small disc osteophyte complex at C6-7. Magnetic resonance imaging (MRI) revealed a central disc protrusion at C4-5 causing severe canal and bilateral neural foramina stenosis with associated T2 signal change within the spinal cord. MRI also revealed a large left paracentral disc herniation at C6-7 with evidence of nerve root compression (Figure 1). As a result of these imaging findings in the setting of intractable radiculopathy with associated early myelopathy, surgical intervention was offered. Due to presence of noncontiguous multi-level degenerative disc disease in a relatively young patient, two-level anterior discectomy and arthroplasty at C4-5 and C6-7 was offered as the best option to decompress neural elements and preserve cervical motion.
Operation
Non-Contiguous Cervical Artificial Disc 3 The precise operative technique has been detailed previously.5 Anterior discectomy at C4-C5 was completed, the endplates of C4-5 were milled, and a 17-mm Bryan disc prosthesis (Medtronic Sofamor-Danek. Memphis, TN) filled with saline was placed in the interspace. Next, a discectomy at C6-C7 was completed as before, in addition to bilateral foraminotomies. A second 17-mm Bryan disc prosthesis filled with saline was placed in the C6-7 interspace. No decompression or instrumentation was done at the intervening C5-6 level.
Postoperative Course and Follow-up The patient tolerated the procedure well without complications and was discharged home on the first postoperative day. Radiographs six weeks after surgery demonstrated intact hardware and stable positioning of both artificial discs at C4-5 and C6-7 (Figure 2). At one year postop, he maintained complete resolution of his previous symptomatology and radiographs continued to demonstrate intact hardware and stable positioning of both Bryan discs without evidence of ASD at the C5-6 intervening level. Flexion/extension films exhibited no evidence of instability (Figure 3). Patient information was de-identified, and therefore consent was not required per our institutional IRB.
Discussion The first use of cervical disc prostheses was described by Goffin et al. to treat single-level degenerative cervical disc disease.5 A number of studies have expanded on the use of artificial discs to treat contiguous multi-level cervical spondylosis. Sekhon et al. first described this technique,3 and would subsequently use CDA as a treatment for ASD in patients who had previously undergone anterior cervical discectomy and fusion (ACDF),6 supporting the use of cervical disc prostheses as an effective treatment for multi-level cervical spondylosis. Li et al. evaluated 20 patients who underwent multi-level CDA and found physiologic movement and lordosis was preserved in all patients during the immediate postoperative period and at last follow-up.7 Song et al. retrospectively analyzed 15 patients over 10 years who underwent two-level disc arthroplasty, and further demonstrated viability of CDA as a long-term treatment paradigm for multi-level cervical spondylosis with the following caveats on the immediate postoperative radiographs: artificial disc-to-endplate coverage ratio must be maintained at 95% or higher and lordosis must be preserved at the level in question.8 Similarly,
Non-Contiguous Cervical Artificial Disc 4 Kim et al. compared a cohort of artificial disc patients to a group who underwent ACDF over a 20-month period, with results supporting the conclusion that CDA was a viable modality for treating multi-level cervical spondylosis while maintaining cervical motion and intervertebral heights.9 There appears to be strong evidence for the use of CDA to treat multi-level cervical pathology as a means of reducing long-term complications associated with fusion surgeries. However, complications with CDA must also be considered, namely heterotopic ossification (HO). Two studies have examined the incidence of HO following CDA with Bryan discs, finding HO in half of the patients and half of the levels treated.10,11 More importantly, higher rates of HO were seen in patients who underwent two-level CDA compared to a single-level procedure. However, despite occurrence of HO in these cases, mobility was maintained in nearly every patient and clinical outcomes were not significantly affected. Moreover, the risk of adjacent segment disease must also be considered, particularly for younger patients. Follow-up results for single-level intervention using artificial disc replacement demonstrated a 6.1% reduction in the number of reoperations at adjacent levels compared to single-level ACDF at 10 years postoperatively.12 Maintenance of cervical range of motion was significantly greater in the CDA group and is thus, partially responsible for the decreased rates of ASD observed in this group. Two studies have examined a series of patients who underwent a two-level, non-contiguous ACDF with at least two years of follow-up, demonstrating incidences of 5.88%13 and 6.25%14 for ASD. Although these results suggest that CDA reduces rates of ASD and rates of ASD at the intervening level in non-contiguous ACDF are non-negligible, long-term follow-up for our multi-level, non-contiguous technique is needed to assess the incidence of ASD. Mechanical stresses placed on the intervening level may predispose to an increased incidence of ASD at that level, although evidence of the non-contiguous technique for ACDF demonstrated a benefit in biomechanical strain at the intervening level compared to three-level fusion.15 Although HO and ASD are known complications following CDA, particularly in multilevel cases, the benefits of CDA appear to favor its use over traditional anterior interbody fusion. The novel approach described in this report for placement of two artificial cervical discs separated by a normal intervening level may provide an even greater benefit compared to ACDF. In young patients, maximizing cervical mobility is particularly important and therefore, three-
Non-Contiguous Cervical Artificial Disc 5 level fusion was less favorable in this case. With our technique, elimination of a fusion construct and bone grafting preserves motion across all three vertebral segments, leading to improved cervical mobility and maintenance of lordosis and sagittal balance. Motion preservation also contributes to a lower incidence of ASD with CDA compared to fusion.12,16 Thus, we argue that treating the non-affected level with fusion is unnecessary and contributes to greater operative risk and potential complications. In young patients, delaying the need for fusion and choosing an approach that maximizes mobility and minimizes risk for developing future complications is of paramount importance.
Conclusion This is the first report detailing a case of cervical disc arthroplasty at two non-adjacent levels for the treatment of cervical myelopathy and radiculopathy due to multi-level disc herniations and stenosis. Cervical motion was preserved, bone grafting was spared, and fusion was avoided compared to management with ACDF. The early result is promising, but long-term follow-up is necessary to assess for development of HO and adjacent segment disease, particularly at the intervening level.
Non-Contiguous Cervical Artificial Disc 6 References 1.
Chang SW, Bohl MA, Kelly BP, Wade C. The segmental distribution of cervical range of motion: A comparison of ACDF versus TDR-C. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2018;57:185-193.
2.
Lavelle WF, Riew KD, Levi AD, Florman JE. 10-year Outcomes of Cervical Disc Replacement with the BRYAN® Cervical Disc: Results from a Prospective, Randomized, Controlled Clinical Trial. Spine. 2018;Publish Ahead of Print.
3.
Sekhon LH. Two-level artificial disc placement for spondylotic cervical myelopathy. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2004;11(4):412-415.
4.
Cardoso MJ, Rosner MK. Multilevel cervical arthroplasty with artificial disc replacement. 2010;28(5):E19.
5.
Goffin J, Casey A, Kehr P, et al. Preliminary clinical experience with the Bryan Cervical Disc Prosthesis. Neurosurgery. 2002;51(3):840-845; discussion 845-847.
6.
Sekhon LH, Sears W, Duggal N. Cervical arthroplasty after previous surgery: results of treating 24 discs in 15 patients. Journal of neurosurgery Spine. 2005;3(5):335-341.
7.
Li Q, Tian W, Liu B, et al. [Clinical outcomes of multi-level cervical Bryan disc replacement]. Zhonghua yi xue za zhi. 2007;87(17):1173-1176.
8.
Song QP, Tian W, He D, et al. [Effect of carpentry of Bryan disc on long-term efficacy of cervical artificial disc replacement]. Zhonghua yi xue za zhi. 2018;98(21):1686-1690.
9.
Kim SW, Limson MA, Kim SB, et al. Comparison of radiographic changes after ACDF versus Bryan disc arthroplasty in single and bi-level cases. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society. 2009;18(2):218-231.
10.
Tu TH, Wu JC, Huang WC, et al. Heterotopic ossification after cervical total disc replacement: determination by CT and effects on clinical outcomes. Journal of neurosurgery Spine. 2011;14(4):457-465.
11.
Wu JC, Huang WC, Tsai HW, et al. Differences between 1- and 2-level cervical arthroplasty: more heterotopic ossification in 2-level disc replacement: Clinical article. Journal of neurosurgery Spine. 2012;16(6):594-600.
Non-Contiguous Cervical Artificial Disc 7 12.
Ghobrial GM, Lavelle WF, Florman JE, Riew KD, Levi AD. Symptomatic Adjacent Level Disease Requiring Surgery: Analysis of 10-Year Results From a Prospective, Randomized, Clinical Trial Comparing Cervical Disc Arthroplasty to Anterior Cervical Fusion. Neurosurgery. 2019;84(2):347-354.
13.
Qizhi S, Peijia L, Lei S, Junsheng C, Jianmin L. Anterior cervical discectomy and fusion for noncontiguous cervical spondylotic myelopathy. Indian Journal of Orthopaedics. 2016;50(4):390-396.
14.
Wang HR, Li XL, Dong J, Yuan FL, Zhou J. Skip-level anterior cervical discectomy and fusion with self-locking stand-alone PEEK cages for the treatment of 2 noncontiguous levels of cervical spondylosis. Journal of spinal disorders & techniques. 2013;26(7):E286-292.
15.
Finn MA, Samuelson MM, Bishop F, Bachus KN, Brodke DS. Two-level noncontiguous versus three-level anterior cervical discectomy and fusion: a biomechanical comparison. Spine (Phila Pa 1976). 2011;36(6):448-453.
16.
Luo J, Wang H, Peng J, et al. Rate of Adjacent Segment Degeneration of Cervical Disc Arthroplasty Versus Fusion Meta-Analysis of Randomized Controlled Trials. World neurosurgery. 2018;113:225-231.
Non-Contiguous Cervical Artificial Disc 8 Figure Legends Figure 1: Preoperative (A) sagittal and axial MR images at (B) C4-5, (C) C5-6, and (D) C6-7. Figure 2: Postoperative Anteroposterior (AP) (left) and Lateral (right) radiographs obtained six weeks after surgery demonstrate intact hardware and maintained alignment of the artificial discs at C4-5 and C6-7. Figure 3: Postoperative AP (A), Lateral (B), Flexion (C), and Extension (D) radiographs obtained one year after surgery demonstrate intact hardware and maintained alignment of the artificial discs at C4-5 and C6-7 with no obvious instability or degeneration of the intervening level.
Abbreviations: ACDF: Anterior cervical discectomy and fusion AP: Anteroposterior ASD: Adjacent segment disease CDA: Cervical disc arthroplasty CT: Computed tomography HO: Heterotopic ossification MRI: Magnetic resonance imaging
Non-Contiguous Cervical Disc Arthroplasty 1
Financial Disclosures Dr. Levi declares the following financial interests/personal relationships which may be considered as potential competing interests: Grant support from the Department of Defense and NIH/NINDS, Teaching Honorarium from AANS and Medtronic. The other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
S1878-8750(19)32634-8
DOI:
https://doi.org/10.1016/j.wneu.2019.10.019
Reference:
WNEU 13490
To appear in:
World Neurosurgery
Received Date: 31 July 2019 Revised Date:
1 October 2019
Accepted Date: 3 October 2019
Please cite this article as: Brusko GD, Luther E, Levi AD, Use of Cervical Disc Arthroplasty to Treat Non-Contiguous Cervical Disc Herniations: A Case Report, World Neurosurgery (2019), doi: https:// doi.org/10.1016/j.wneu.2019.10.019. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Elsevier Inc. All rights reserved.
Non-Contiguous Cervical Artificial Disc 1 Use of Cervical Disc Arthroplasty to Treat Non-Contiguous Cervical Disc Herniations: A Case Report G. Damian Brusko, BS,1 Evan Luther, MD,1 and Allan D. Levi, MD, PhD1 1
Department of Neurological Surgery
University of Miami Miller School of Medicine Lois Pope Life Center 1095 NW 14th Terrace Miami, Florida, U.S.A 33136
Corresponding author: G. Damian Brusko Lois Pope Life Center Department of Neurological Surgery 1095 NW 14th Terrace Miami, FL 33136 Tel.: (305) 243-3294 Fax: (305) 243-3337 Email: [email protected]
Keywords: Arthroplasty, Bryan Disc, Cervical, Disc Herniation, Fusion, Multi-Level
Running Head: Non-Contiguous Cervical Artificial Disc
Non-Contiguous Cervical Artificial Disc 1 Abstract Background Cervical disc arthroplasty (CDA) is now a widely accepted alternative to anterior cervical interbody fusion, which is known to reduce normal cervical motion and increase the incidence of adjacent segment disease. Although multiple studies report the use of cervical disc arthroplasty to treat multi-level cervical disease, this is the first report in the literature detailing the placement of multiple, non-contiguous artificial discs. Case Description We describe a 41-year-old male who presented with myelopathy and left upper extremity radiculopathy resulting from two cervical disc herniations separated by a normal intervening level. He underwent an anterior cervical discectomy and placement of an artificial disc prosthesis at cervical (C) 4-5 and C6-7 while leaving C5-6 intact. Conclusion This approach serves to preserve cervical motion, spinal stability, and lordosis across all three levels, thus demonstrating that it is a viable alternative to a multi-level anterior cervical interbody fusion.
Non-Contiguous Cervical Artificial Disc 2 Background Cervical disc arthroplasty (CDA) is a widely accepted alternative to anterior cervical interbody fusion, which is known to reduce cervical motion and increase the incidence of adjacent segment disease (ASD).1 In a randomized, controlled clinical trial with an artificial disc prosthesis, CDA demonstrated improved outcomes related to segment motion, reoperation at adjacent segments, and neck pain.2 To treat contiguous multi-level disease, the CDA has been increasingly employed since the first reported case in 2003.3 Previous reports have mentioned the use of CDA to treat multilevel non-contiguous cervical spondylosis but analysis of these patients and long-term outcomes still remain limited.4 Thus, no published studies to date describe placement of two artificial discs at non-adjacent cervical levels with subsequent patient followup. We present a case of a 41-year-old male with disc herniations at C4-5 and C6-7 who underwent two-level anterior decompression with placement of an artificial disc at each affected level.
Case Description Clinical Presentation A 41-year old male presented with a two-month history of severe neck pain radiating down the left arm, primarily into the shoulder. Initial computed tomography (CT) scan demonstrated a C4-5 disc extrusion and a small disc osteophyte complex at C6-7. Magnetic resonance imaging (MRI) revealed a central disc protrusion at C4-5 causing severe canal and bilateral neural foramina stenosis with associated T2 signal change within the spinal cord. MRI also revealed a large left paracentral disc herniation at C6-7 with evidence of nerve root compression (Figure 1). As a result of these imaging findings in the setting of intractable radiculopathy with associated early myelopathy, surgical intervention was offered. Due to presence of noncontiguous multi-level degenerative disc disease in a relatively young patient, two-level anterior discectomy and arthroplasty at C4-5 and C6-7 was offered as the best option to decompress neural elements and preserve cervical motion.
Operation
Non-Contiguous Cervical Artificial Disc 3 The precise operative technique has been detailed previously.5 Anterior discectomy at C4-C5 was completed, the endplates of C4-5 were milled, and a 17-mm Bryan disc prosthesis (Medtronic Sofamor-Danek. Memphis, TN) filled with saline was placed in the interspace. Next, a discectomy at C6-C7 was completed as before, in addition to bilateral foraminotomies. A second 17-mm Bryan disc prosthesis filled with saline was placed in the C6-7 interspace. No decompression or instrumentation was done at the intervening C5-6 level.
Postoperative Course and Follow-up The patient tolerated the procedure well without complications and was discharged home on the first postoperative day. Radiographs six weeks after surgery demonstrated intact hardware and stable positioning of both artificial discs at C4-5 and C6-7 (Figure 2). At one year postop, he maintained complete resolution of his previous symptomatology and radiographs continued to demonstrate intact hardware and stable positioning of both Bryan discs without evidence of ASD at the C5-6 intervening level. Flexion/extension films exhibited no evidence of instability (Figure 3). Patient information was de-identified, and therefore consent was not required per our institutional IRB.
Discussion The first use of cervical disc prostheses was described by Goffin et al. to treat single-level degenerative cervical disc disease.5 A number of studies have expanded on the use of artificial discs to treat contiguous multi-level cervical spondylosis. Sekhon et al. first described this technique,3 and would subsequently use CDA as a treatment for ASD in patients who had previously undergone anterior cervical discectomy and fusion (ACDF),6 supporting the use of cervical disc prostheses as an effective treatment for multi-level cervical spondylosis. Li et al. evaluated 20 patients who underwent multi-level CDA and found physiologic movement and lordosis was preserved in all patients during the immediate postoperative period and at last follow-up.7 Song et al. retrospectively analyzed 15 patients over 10 years who underwent two-level disc arthroplasty, and further demonstrated viability of CDA as a long-term treatment paradigm for multi-level cervical spondylosis with the following caveats on the immediate postoperative radiographs: artificial disc-to-endplate coverage ratio must be maintained at 95% or higher and lordosis must be preserved at the level in question.8 Similarly,
Non-Contiguous Cervical Artificial Disc 4 Kim et al. compared a cohort of artificial disc patients to a group who underwent ACDF over a 20-month period, with results supporting the conclusion that CDA was a viable modality for treating multi-level cervical spondylosis while maintaining cervical motion and intervertebral heights.9 There appears to be strong evidence for the use of CDA to treat multi-level cervical pathology as a means of reducing long-term complications associated with fusion surgeries. However, complications with CDA must also be considered, namely heterotopic ossification (HO). Two studies have examined the incidence of HO following CDA with Bryan discs, finding HO in half of the patients and half of the levels treated.10,11 More importantly, higher rates of HO were seen in patients who underwent two-level CDA compared to a single-level procedure. However, despite occurrence of HO in these cases, mobility was maintained in nearly every patient and clinical outcomes were not significantly affected. Moreover, the risk of adjacent segment disease must also be considered, particularly for younger patients. Follow-up results for single-level intervention using artificial disc replacement demonstrated a 6.1% reduction in the number of reoperations at adjacent levels compared to single-level ACDF at 10 years postoperatively.12 Maintenance of cervical range of motion was significantly greater in the CDA group and is thus, partially responsible for the decreased rates of ASD observed in this group. Two studies have examined a series of patients who underwent a two-level, non-contiguous ACDF with at least two years of follow-up, demonstrating incidences of 5.88%13 and 6.25%14 for ASD. Although these results suggest that CDA reduces rates of ASD and rates of ASD at the intervening level in non-contiguous ACDF are non-negligible, long-term follow-up for our multi-level, non-contiguous technique is needed to assess the incidence of ASD. Mechanical stresses placed on the intervening level may predispose to an increased incidence of ASD at that level, although evidence of the non-contiguous technique for ACDF demonstrated a benefit in biomechanical strain at the intervening level compared to three-level fusion.15 Although HO and ASD are known complications following CDA, particularly in multilevel cases, the benefits of CDA appear to favor its use over traditional anterior interbody fusion. The novel approach described in this report for placement of two artificial cervical discs separated by a normal intervening level may provide an even greater benefit compared to ACDF. In young patients, maximizing cervical mobility is particularly important and therefore, three-
Non-Contiguous Cervical Artificial Disc 5 level fusion was less favorable in this case. With our technique, elimination of a fusion construct and bone grafting preserves motion across all three vertebral segments, leading to improved cervical mobility and maintenance of lordosis and sagittal balance. Motion preservation also contributes to a lower incidence of ASD with CDA compared to fusion.12,16 Thus, we argue that treating the non-affected level with fusion is unnecessary and contributes to greater operative risk and potential complications. In young patients, delaying the need for fusion and choosing an approach that maximizes mobility and minimizes risk for developing future complications is of paramount importance.
Conclusion This is the first report detailing a case of cervical disc arthroplasty at two non-adjacent levels for the treatment of cervical myelopathy and radiculopathy due to multi-level disc herniations and stenosis. Cervical motion was preserved, bone grafting was spared, and fusion was avoided compared to management with ACDF. The early result is promising, but long-term follow-up is necessary to assess for development of HO and adjacent segment disease, particularly at the intervening level.
Non-Contiguous Cervical Artificial Disc 6 References 1.
Chang SW, Bohl MA, Kelly BP, Wade C. The segmental distribution of cervical range of motion: A comparison of ACDF versus TDR-C. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2018;57:185-193.
2.
Lavelle WF, Riew KD, Levi AD, Florman JE. 10-year Outcomes of Cervical Disc Replacement with the BRYAN® Cervical Disc: Results from a Prospective, Randomized, Controlled Clinical Trial. Spine. 2018;Publish Ahead of Print.
3.
Sekhon LH. Two-level artificial disc placement for spondylotic cervical myelopathy. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia. 2004;11(4):412-415.
4.
Cardoso MJ, Rosner MK. Multilevel cervical arthroplasty with artificial disc replacement. 2010;28(5):E19.
5.
Goffin J, Casey A, Kehr P, et al. Preliminary clinical experience with the Bryan Cervical Disc Prosthesis. Neurosurgery. 2002;51(3):840-845; discussion 845-847.
6.
Sekhon LH, Sears W, Duggal N. Cervical arthroplasty after previous surgery: results of treating 24 discs in 15 patients. Journal of neurosurgery Spine. 2005;3(5):335-341.
7.
Li Q, Tian W, Liu B, et al. [Clinical outcomes of multi-level cervical Bryan disc replacement]. Zhonghua yi xue za zhi. 2007;87(17):1173-1176.
8.
Song QP, Tian W, He D, et al. [Effect of carpentry of Bryan disc on long-term efficacy of cervical artificial disc replacement]. Zhonghua yi xue za zhi. 2018;98(21):1686-1690.
9.
Kim SW, Limson MA, Kim SB, et al. Comparison of radiographic changes after ACDF versus Bryan disc arthroplasty in single and bi-level cases. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society. 2009;18(2):218-231.
10.
Tu TH, Wu JC, Huang WC, et al. Heterotopic ossification after cervical total disc replacement: determination by CT and effects on clinical outcomes. Journal of neurosurgery Spine. 2011;14(4):457-465.
11.
Wu JC, Huang WC, Tsai HW, et al. Differences between 1- and 2-level cervical arthroplasty: more heterotopic ossification in 2-level disc replacement: Clinical article. Journal of neurosurgery Spine. 2012;16(6):594-600.
Non-Contiguous Cervical Artificial Disc 7 12.
Ghobrial GM, Lavelle WF, Florman JE, Riew KD, Levi AD. Symptomatic Adjacent Level Disease Requiring Surgery: Analysis of 10-Year Results From a Prospective, Randomized, Clinical Trial Comparing Cervical Disc Arthroplasty to Anterior Cervical Fusion. Neurosurgery. 2019;84(2):347-354.
13.
Qizhi S, Peijia L, Lei S, Junsheng C, Jianmin L. Anterior cervical discectomy and fusion for noncontiguous cervical spondylotic myelopathy. Indian Journal of Orthopaedics. 2016;50(4):390-396.
14.
Wang HR, Li XL, Dong J, Yuan FL, Zhou J. Skip-level anterior cervical discectomy and fusion with self-locking stand-alone PEEK cages for the treatment of 2 noncontiguous levels of cervical spondylosis. Journal of spinal disorders & techniques. 2013;26(7):E286-292.
15.
Finn MA, Samuelson MM, Bishop F, Bachus KN, Brodke DS. Two-level noncontiguous versus three-level anterior cervical discectomy and fusion: a biomechanical comparison. Spine (Phila Pa 1976). 2011;36(6):448-453.
16.
Luo J, Wang H, Peng J, et al. Rate of Adjacent Segment Degeneration of Cervical Disc Arthroplasty Versus Fusion Meta-Analysis of Randomized Controlled Trials. World neurosurgery. 2018;113:225-231.
Non-Contiguous Cervical Artificial Disc 8 Figure Legends Figure 1: Preoperative (A) sagittal and axial MR images at (B) C4-5, (C) C5-6, and (D) C6-7. Figure 2: Postoperative Anteroposterior (AP) (left) and Lateral (right) radiographs obtained six weeks after surgery demonstrate intact hardware and maintained alignment of the artificial discs at C4-5 and C6-7. Figure 3: Postoperative AP (A), Lateral (B), Flexion (C), and Extension (D) radiographs obtained one year after surgery demonstrate intact hardware and maintained alignment of the artificial discs at C4-5 and C6-7 with no obvious instability or degeneration of the intervening level.
Abbreviations: ACDF: Anterior cervical discectomy and fusion AP: Anteroposterior ASD: Adjacent segment disease CDA: Cervical disc arthroplasty CT: Computed tomography HO: Heterotopic ossification MRI: Magnetic resonance imaging
Non-Contiguous Cervical Disc Arthroplasty 1
Financial Disclosures Dr. Levi declares the following financial interests/personal relationships which may be considered as potential competing interests: Grant support from the Department of Defense and NIH/NINDS, Teaching Honorarium from AANS and Medtronic. The other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.