Comparison of the long-term efficacy of two-level cervical artificial disc replacement and anterior cervical decompression and fusion / 中华骨科杂志

Objective:To compare the long-term efficacy of two-level cervical artificial disc replacement (CADR) and anterior cervical decompression and fusion (ACDF) in the treatment of cervical degenerative diseases.Methods:A retrospective analysis was performed on patients who had received two-level anterior cervical surgery for cervical degenerative diseases for more than 15 years from December 2003 to December 2007. The patients were divided into two groups: CADR and ACDF according to surgical methods. There were 15 patients in the CADR group, including 7 males and 8 females, with an average age of 49.73±10.26 (range, 32-70) years. Three cases of mixed cervical spondylosis, 5 cases of cervical spondylotic radiculopathy, 7 cases of cervical spondylotic myelopathy, including C 3, 4 and C 4, 5 level 1 case, C 3, 4 and C 5, 6 level 2 cases, C 4, 5 and C 5, 6 level 7 cases, C 5, 6 and C 6, 7 level 5 cases, operative segment range of motion (ROM) was 9.10°±4.00°. The follow-up time in the CADR group was 189.07±13.51 (range, 162-210) months. There were 20 patients in the ACDF group, including 12 males and 8 females, with an average age of 52.60±8.83 (range, 32-68) years. Two cases of mixed cervical spondylosis, 3 cases of cervical spondylotic radiculopathy, 15 cases of cervical spondylotic myelopathy, including C 3, 4 and C 4, 5 level 1 case, C 4, 5 and C 5, 6 level 15 cases, C 5, 6 and C 6, 7 level 4 cases, the ROM of the surgical segment was 8.31±5.23°. The mean follow-up time of ACDF group was 184.20±21.39 (range, 156-222) months. The Japanese Orthopaedic Association (JOA) score and neck disability index (NDI) were evaluated preoperatively and at the last follow-up. The overall ROM of the cervical spine, ROM of the surgical segment, and Miyazaki grading of the adjacent intervertebral disc, Odom score and complications of the two groups were evaluated at the last follow-up. Results:In the CADR group, the JOA score improved from 13.20±2.64 preoperatively to 15.93±1.22 at last follow-up, and NDI improved from 27.60%±6.44% preoperatively to 15.07%±9.71% at last follow-up, JOA improvement rate was 59.44%±60.86%, and NDI decreased by 12.53%±9.64%. In the ACDF group, JOA score improved from 12.93±2.46 preoperatively to 15.65±1.25 at last follow-up, NDI improved from 30.80%±8.11% preoperatively to 12.80%±6.31% at last follow-up, JOA improvement rate was 60.51%±43.17%, NDI decreased by 18.00%±8.34%. There was no significant difference in JOA and NDI between the two groups before surgery and at the last follow-up. At the last follow-up, the overall ROM of the cervical spine in the CADR group was 38.33°±12.31°, the ROM of the surgical segment was 6.51°±4.61°, and the overall ROM of the cervical spine in the ACDF group was 31.11°±8.65°, the ROM of the surgical segment was 0°. There was a significant difference in the overall ROM of the cervical spine between the two groups at the last follow-up ( t=7.22, P=0.049). The incidence of increased Miyazaki grading of the upper and lower adjacent segment of the cervical intervertebral disc in the CADR group were 40% and 47%, and the rate of new intervertebral disc herniation were 20% and 13%. The incidence of increased Miyazaki grading of the upper and lower adjacent segment of the cervical intervertebral disc in the ACDF group were 45% and 50%, and the incidence of new herniated disc were 25% and 40%, there is a significant difference in the degeneration rate of the lower adjacent segments between the two groups (χ 2=4.38, P=0.036). At the last follow-up, the excellent and good rate of Odom in the CADR group was 80%, and 1 case was revised; the excellent and good rate of Odom in the ACDF group was 85%, and 1 case was revised. There was no significant difference in the overall efficacy between the two groups. Conclusion:The long-term clinical efficacy of two-level CADR is comparable to that of traditional ACDF, and it preserved the ROM of the surgical segment, and is superior to ACDF in terms of the overall cervical spine ROM, and the incidence of adjacent segment degeneration.

Results of Total Cervical Disc Replacement with a Minimum Follow-up of 10 Years / Resultados da artroplastia total de disco cervical com acompanhamento mínimo de 10 anos

Abstract Objective In the present study, we present the results with at least 10 years of follow-up of the cervical disc prosthesis implanted in a single level. Methods Retrospective study of patients undergoing single-level total cervical disc replacement (TCDR). Clinical results included the neck disability index (NDI) and the visual analogue scale (VAS) in the preoperative period, one year postoperatively, and a minimum of 10 years of follow-up. The radiographic parameters included cervical mobility, segmental lordosis, C2-C7 angle, heterotopic ossification (HO), facet and joint degeneration (FJD) and adjacent segment disease (ASD). Results We identified 22 patients, 16 women and 6 men with mean age of 39.7 years old (26-51 years old), of which fifteen completed a minimum follow-up of 10 years. There was a statistically significant improvement of NDI and VAS (p < 0.001) between the preoperative and the postoperative periods (1 year or > 10 years). At the end of 10 years, HO was observed in 59% of the cases. The mobility of the implant was preserved in 80% of the patients. Radiological evidence of ASD was recorded in 6 patients (40%). There was no correlation between the clinical parameters evaluated and the presence of ASD or the different classes of HO. Conclusion Clinical improvement in all evaluated parameters, which persists over time. Most implants maintained mobility, as has already been demonstrated in other studies with shorter follow-ups. In a significant percentage of cases, ASD was observed, questioning the concept of motion preserving technology. However, we did not have any surgical intervention for this reason, since there was no correlation with worse clinical results.

Resumo Objetivo No presente estudo, apresentamos os resultados com um acompanhamento mínimo de 10 anos da artroplastia total do disco cervical (ATDC) em um nível. Métodos Estudo retrospectivo de pacientes submetidos a ATDC em um nível. Os resultados clínicos incluíram o índice de incapacidade relacionada ao pescoço (IIRP) e a escala visual analógica (EVA) no período pré-operatório, um ano pós-operatório e um mínimo de 10 anos de acompanhamento. Os parâmetros radiográficos incluíram a mobilidade cervical, lordose segmentar, ângulo C2-C7, ossificação heterotópica (OH), degeneração facetária e articular (DFA) e doença do segmento adjacente (DSA). Resultados Identificados 22 pacientes, 16 mulheres e 6 homens com média de idade de 39,7 anos (26-51 anos), dos quais 15 tiveram um acompanhamento mínimo de 10 anos. Foi verificada melhoria estatisticamente significativa do IIRP e EVA (p < 0,001) entre pré-operatório e pós-operatório. (1 ano ou > 10 anos). Ao final de 10 anos, OH foi observada em 59% dos casos. A mobilidade do implante foi preservada em 80% dos pacientes. Houve evidência radiológica de DSA em 6 pacientes (40%). Não houve correlação entre os parâmetros clínicos avaliados e a presença de DSA ou as diferentes classes de OH. Conclusão Melhoria clínica em todos os parâmetros avaliados, que persiste ao longo do tempo. A maioria dos implantes manteve a mobilidade, como já demonstrado em estudos anteriores com acompanhamentos mais curtos. Numa percentagem significativa, a DSA estava presente, questionando o conceito da tecnologia de preservação de movimento. No entanto, sem nenhuma intervenção cirúrgica por esse motivo, uma vez que não houve correlação com piores resultados clínicos.

Effect of heterotopic ossification on cervical motion following Prestige artificial cervical disc replacement / 解剖学报

[Abstract] Objective To analyze the effect of heterotopic ossification(HO) on the postoperative segmental range of motion(ROM)after Prestige artificial cendcal disc replacement, and to explore the related factors leading to the formation of heterotopic ossification after artificial cendcal disc replacement. Methods We recruited of 66 patients who had Prestige artificial cendcal disc replacement from January 2014 to January 2018 in Department of Orthopedics, the First Affiliated Hospital of Chongqing Medical University were retrospectively reviewed. To evaluate cendcal spine X-ray, the replacement segment ROM was measured in picture, and the occurrence of HO was defined by the McAfee' s classification. The Wilcoxon signed rank test was used to analyze the relationship between heterotopic ossification formation and replacement segment ROM,the t test was used to analyze the influence between heterotopic ossification grading and replacement segment ROM. Nine clinical factors including age, gender, bod)' mass index(BMI), number of replacement segments, preoperative ligament ossification, the preoperative disc height ratio of the target level and its adjacent level, preoperative mobility of replacement segments, postoperative mobility of replacement segments, whether to use nonsteroidal autiinflammatory drugs (NSAIDs) during perioperative period. The correlation between these nine clinical factors and the occurrence of postoperative HO was evaluated with logistic regression analysis. Results The occurrence rate of HO was 34. 8% in last follow-up. The replacement segmental ROM of the heterotopic ossification group was significantly smaller than that of the non-ectopic ossification group, and the difference was statistically significant (P<0. 05),and the McAfee grade IH-IV group was significantly less than the McAfee grade I-H group, and the difference was statistically significant (P < 0. 05). Correlation analysis showed that preoperative and postoperative ROM of the replacement segment presented statistical correlation (P < 0. 05). Furthennore analysis of ROC curve showed that heterotopic ossification was more likely to occur when the degree of ROM of the replacement segment

A network meta-analysis of different surgical methods in the treatment of lumbar disc herniation / 中国组织工程研究

BACKGROUND: At present, there are many surgical methods for the treatment of lumbar disc herniation, and the therapeutic effects have their own advantages. Although there are many meta-analyses to compare the therapeutic effects of the two surgical methods, there is no comparison of the therapeutic effects of several surgical methods. OBJECTIVE: To compare the differences of different surgical methods in the treatment of lumbar disc herniation by network meta-analysis. METHODS: PubMed, Embase, Cochrane Library, Ovid and CNKI were searched, and randomized controlled trials or retrospective studies on different surgical methods for the treatment of lumbar disc herniation were collected. According to the inclusion and exclusion criteria established in advance, the quality of included randomized controlled trials was evaluated, and the data were analyzed by STATA 15.0 software. RESULTS AND CONCLUSION: A total of 42 studies, 5 156 patients and 9 surgical treatments were included. Surgical treatments contain total disc replacement, lumbar disc fusion, standard open discectomy, microendoscopic discectomy, microdiscectomy, percutaneous endoscopic lumbar discectomy, chemonucleolysis, automatic percutaneous lumbar discectomy and percutaneous laser disc decompression. The results of network meta-analysis showed that(from best to worst):(1) There was no significant difference in leg pain relief, and the rank probability was percutaneous laser disc decompression > microendoscopic discectomy > percutaneous endoscopic lumbar discectomy > standard open discectomy > microdiscectomy > lumbar disc fusion > total disc replacement.(2) There was no significant difference in low back pain relief, and the rank probability was total disc replacement > lumbar disc fusion > microendoscopic discectomy > percutaneous endoscopic lumbar discectomy > microdiscectomy > percutaneous laser disc decompression > standard open discectomy.(3) There was no significant difference in Oswestry disability index scores, and the rank probability was microendoscopic discectomy > percutaneous endoscopic lumbar discectomy > standard open discectomy > microdiscectomy > total disc replacement > lumbar disc fusion.(4) There were some statistical differences in the success rate, and the rank probability was total disc replacement > lumbar disc fusion > microendoscopic discectomy > percutaneous endoscopic lumbar discectomy > standard open discectomy > percutaneous laser disc decompression > microdiscectomy > chemonucleolysis > automatic percutaneous lumbar discectomy.(5) There was no significant difference in reoperation rate, and the rank probability was total disc replacement > lumbar disc fusion > microdiscectomy > microendoscopic discectomy > standard open discectomy > percutaneous endoscopic lumbar discectomy > percutaneous laser disc decompression > chemonucleolysis > automatic percutaneous lumbar discectomy.(6) There were some statistical differences in incidence of complications, and the rank probability was percutaneous endoscopic lumbar discectomy > automatic percutaneous lumbar discectomy > standard open discectomy > microdiscectomy > percutaneous laser disc decompression > microendoscopic discectomy > total disc replacement > lumbar disc fusion > chemonucleolysis. Results suggested that microendoscopic discectomy and percutaneous endoscopic lumbar discectomy are effective in all aspects. Disc replacement and lumbar disc fusion are the best in success rate of operation. Chemonucleolysis is poor in success rate of operation, reoperation rate and complications rate. Percutaneous automatic discectomy is poor in success rate of operation and reoperation rate.

Analysis and prediction of related factors of single-level cervical total disc replacement / 中国组织工程研究

BACKGROUND: There is limited anterior cervical spine space. Incomplete hemostasis or drainage during artificial cervical total disc replacement can incur a series of complications. Preoperative factors can directly affect the amount of bleeding during spine surgery, while there are no publications aiming at cervical artificial disc replacement. OBJECTIVE: To analyze influencing factors on operation time and hemorrhage in patients undergoing single cervical total disc replacement. METHODS: Fifty-six patients with cervical spondylosis who underwent cervical total disc replacement from October 2012 to December 2017 in Department of Spine Surgery, Peking University People’s Hospital, were retrospectively enrolled. Pre- and intra-operative related parameters were measured. Primary outcomes included operation time, intraoperative blood loss and postoperative drainage. The secondary outcomes included demographic data such as sex, male and hypertension; surgery-related information such as operated segment, types of cervical spondylosis and artificial prosthesis; parameters in X-ray plain films such as the motion range and cervical lordosis of C2-C7 and index segment, the height of intervertebral disc, MRI classification (Modic classification and Pfirrmann classification) and preoperative functional score. The analysis was performed between primary and secondary outcomes as well as among primary outcomes. RESULTS AND CONCLUSION: (1) The average age of 56 patients (30 males and 26 females) was 48.2±9.8 years; operation time, intraoperative bleeding and postoperative drainage were 73.2±13.4 minutes, 51.8±41.2 mL and 7.8±5.3 mL, respectively. (2) There were no differences both in operation time and intraoperative blood loss in terms of demographics, while the drainage was statistically different in various ages (P=0.030). (3) The operation time of Prestige-LP implantation was statistically shorter than that of Mobi-C and Prodisc-C (P < 0.05). There was a positive correlation between the intermittent on taking (nonsteroidal anti-inflammatory drugs) and intraoperative blood loss (r=0.310, P=0.020). The higher intervertebral disc of the operation segment was, the longer operation time was (P=0.028). (4) There was a significant difference in more intraoperative blood loss with osteoporosis compared to the normal ones (P=0.039); while the rest radiological parameters in X-ray were in no relation to primary outcomes, neither were in MRI degree, Modic change and Pfirrmann classification. (5) There was a positive correlation between operation time and intraoperative blood loss (P=0.010) and postoperative drainage (P=0.001). (6) These indicate that the height of intervertebral space can prolong operation time. Osteoporosis is a risk factor for intraoperative blood loss. The longer the operation time is, the more intraoperative blood loss and postoperative drainage will be.

Long-term outcomes of cervical artificial disc replacement for patients with degenerative cervical canal stenosis / 中华骨科杂志

Objective To evaluate the long-term efficacy of cervical artificial disc replacement for patients with degenerative cervical canal stenosis.Methods All of 43 patienta underwent single level Bryan cervical artificial disc replacement for degenerative cervical canal stenosis were retrospectively analyzed with a minimum 10 years follow-up in our hospital between December 2003 and December 2007.There were 28 males and 15 females with an average age of 56.7 ± 8.0 years which ranged from 37 to 76 including 1 case of C3.4 level,11 xases of ~ level,26 cases of C~ level and 5 cases of C6,7 level.According to the symptoms and location of compression on radiograph,the patients were divided into 3 groups:15 patients in radiculopathy group,10 patients in myelopathy group and 18 patients in myeloradiculo p~hy group.Radidogical evaluation indexes include global range of motion (ROM),segmental ROM,segmental Cobb angle.Clinical evaluation indexes including Japanese Orthopaedic Association (JOA) score,neck disability index (NDI) and Odom's criteria.The variable data were analyzed by one-way ANOVA,the grading data were analyzed by Kruskal-Wallis H test.The preoperative and postoperative data were analyzed by paired t test.Results At the last follow-up,the Cobb angle of the operative segment was 1.29°±1.34°in myelopathy group(t=4.606,P=0.001),0.71°±2.20°in radiculopathy group (t=2.355,P=0.034),and 0.69°±2.12° in myeloradiculopathy group (t=3.312,P=0.004),which was significantly lower than that before operation.At the last follow-up,ROM of the operative segment in myelopathy group was 6.41 o ±4.87°,which was significantly lower than that before operation (11.46° ±5.19°,t=3.589,P＜ 0.05),and there was no significant difference in the other two groups.There was no significant difference in other imaging parameters among the three groups.JOA scores at the last follow-up were 16.33±0.75 in radiculopathy group (t=5.857,P＜ 0.001),16.00±1.05 in myelopathy group(t=8.337,P＜ 0.001) and 14.78±1.69 in radiculopathy group (t=4.045,P＜ 0.001);NDI were 13.07％±5.90％ in radiculopathy group (t=7.097,P＜ 0.001),12.60％±4.22％ in myelopathy group (t=7.319,P＜ 0.001) and 23.11％±14.18％ in radiculopathy group (t=4.229,P＜ 0.001),which were all significantly improved than those before operation.The excellent and good rate of Odom's criteria (H=2.719,2.411,P＜ 0.05),JOA (LAD-t=3.770,4.080,P＜0,05) and NDI(LAD-t=2.850,2.643,P＜ 0.05) at the last follow-up of the patients in radiculopathy group and myelopathy group were better than those of patients in myeloradiculopathy group (P＜ 0.05).Conclusion Cervical artificial disc replacement has a satisfied long-term clinical efficacy with degenerative cervical canal stenosis.The efficacy of myelopathy and radiculopathy were better than myeloradiculopathy.

Cost-Effectiveness Analysis of Cervical Anterior Fusion and Cervical Artificial Disc Replacement in the Korean Medical System

OBJECTIVE: This study is a retrospective cost-benefit analysis of cervical anterior interbody fusion and cervical artificial disc replacement, which are the main surgical methods to treat degenerative cervical disc disease.METHODS: We analyzed 156 patients who underwent anterior cervical disc fusion and cervical artificial disc replacement from January 1, 2008 to December 31, 2009, diagnosed with degenerative cervical disc disorder. In this study, the costs and benefits were analyzed by using quality adjusted life year (QALY) as the outcome index for patients undergoing surgery, and a Markov model was used for the analysis. Only direct medical costs were included in the analysis; indirect medical costs were excluded. Data were analyzed with TreeAge Pro 2015™ (TreeAge Software, Inc, Williamstown, MA, USA).RESULTS: Patients who underwent cervical anterior fusion had a total cost of KRW 2501807/USD 2357 over 5 years and obtained a utility of 3.72 QALY. Patients who underwent cervical artificial disc replacement received 4.18 QALY for a total of KRW 3685949/USD 3473 over 5 years. The cumulative cost-effectiveness ratio of cervical spine replacement surgery was KRW 2549511/QALY (USD 2402/QALY), which was lower than the general Korean payment standard.CONCLUSION: Both cervical anterior fusion and cervical artificial disc replacement are cost-effective treatments for patients with degenerative cervical disc disease. Cervical artificial disc replacement may be an effective alternative to obtain more benefits.

Effectiveness evaluation of Prodisc-C prosthesis for more than 10 years follow-up after total cervical disc replacement / 中国修复重建外科杂志

Objective: To evaluate long-term radiographic and clinical effectiveness of total cervical disc replacement (TDR) with Prodisc-C prosthesis at a minimum of 10 years follow-up. Methods: The clinical data of 118 patients with cervical disc degeneration disease (CDDD) treated with TDR by using Prodisc-C prosthesis between December 2005 and April 2008 were retrospectively analyzed. There were 66 males and 52 females, with the age of 25-62 years (mean, 46.8 years). There were 38 cases of cervical spondylotic radiculopathy, 28 cases of cervical spondylotic myelopathy, and 52 cases of mixed cervical spondylotic myelopathy. The operative segments were C 3-7, including 90 cases of single segment, 20 cases of continuous double segments, and 8 cases of continuous three segments. A total of 154 Prodisc-C prostheses were used during the operation. The clinical effectiveness was evaluated by pain visual analogue scale (VAS) score, neck disability index (NDI), Japanese Orthopaedic Association (JOA) score, and Odom grade before and after operation. Imaging evaluation indicators included range of motion (ROM), sagittal lordosis angle, intervertebral disc height (IDH), and prosthesis displacement, subsidence, loosening, locking, and heterotopic ossification (HO), adjacent segment degeneration (ASD), and other complications. Patients were grouped according to whether HO or ASD occurred or not, the ROM of surgical segment was compared. Results: All patients were followed up 121-150 months (mean, 135.8 months). No revision operation was performed during the follow-up period. The VAS, NDI, JOA scores and Odom grades were significantly improved at 1 week after operation and last follow-up when compared with preoperative ones ( P0.05). The ROM of the whole cervical spine and the operative segment decreased at 1 week and 10 years after operation when compared with preoperative ones ( P0.05); there was no significant difference in the ROM between the upper adjacent segment (UAS) and the lower adjacent segment (LAS) at each time point after operation ( P>0.05). There was no significant difference in sagittal lordosis angle of cervical spine before and after operation ( P>0.05); the sagittal lordosis angle of operative segment increased significantly at 1 week, 6 months, 1 year, and 2 years after operation ( P0.05). No prosthesis displacement, subsidence, or loosening occurred at each time point after operation. There was no significant difference of the prosthetic displacement and subsidence distance between all time points after 6 months after operation ( P>0.05). At last follow-up, the incidence of prosthetic locking/fusion was 10.4%, showing no significant difference when compared with 6 months (1.9%) ( P0.05). HO appeared in 58.4% of the segments at 6 months after operation, and the incidence of HO increased significantly with time, which was significantly different from that at 6 months after operation ( P<0.05). The ROM of operative segments in HO group was significantly lower than that in non-HO group at 6 months, 2 years, 5 years, and 10 years after operation ( P<0.05). Conclusion: TDR has little effect on adjacent segments, although there are some imaging complications, it has no significant effect on the improvement of overall clinical effectiveness. Prodisc-C prosthesis can provide long-term, safe, and definite clinical effectiveness in the treatment of CDDD.

Progression of Ossification of the Posterior Longitudinal Ligament after Cervical Total Disc Replacement / 대한신경손상학회지

OBJECTIVE: Total disc replacement (TDR) is frequently performed anterior approaching method for the patients diagnosed with cervical disc herniation. This study aimed to assess the degree of ossification of the posterior longitudinal ligament (OPLL) progression after cervical TDR. METHODS: Twenty-two male soldiers who underwent cervical TDR surgery from 2009 to 2016 and were followed-up for more than 12 months were enrolled. The enrolled patients were classified as; 1) patients with pre-existing OPLL and without; and 2) patient showing progression of OPLL or not. RESULTS: Twenty-two men were included in the analysis. The mean follow-up period from the surgery was 41.4 months (range, 12–114 months). The mean age of all patients was 40.7 years (range, 31–52 years). TDR-only was used in 7 cases, and the hybrid surgery (TDR+ACDF) was used in 15 cases. The incidence of progression or newly development of OPLL was significantly higher in pre-existing OPLL group (p=0.01). In 11 cases showing the progression of the OPLL, the mean size of OPLL progression was 4.16 mm (range, 0.34–18.87 mm) in the longitudinal height and 1.57 mm (range, 0.54–3.91 mm) in thickness. CONCLUSION: The progression of OPLL after cervical TDR was more frequent in patients with pre-existing OPLL than in patients without OPLL. Even though TDR is a major alternative to the treatment of cervical lesions to preserve vertebral segmental motion, careful attention should be paid to whether TDR should be used in patients with OPLL and this should be fully explained to the patient.

Cost-Effectiveness Analysis of Cervical Anterior Fusion and Cervical Artificial Disc Replacement in the Korean Medical System

OBJECTIVE: This study is a retrospective cost-benefit analysis of cervical anterior interbody fusion and cervical artificial disc replacement, which are the main surgical methods to treat degenerative cervical disc disease. METHODS: We analyzed 156 patients who underwent anterior cervical disc fusion and cervical artificial disc replacement from January 1, 2008 to December 31, 2009, diagnosed with degenerative cervical disc disorder. In this study, the costs and benefits were analyzed by using quality adjusted life year (QALY) as the outcome index for patients undergoing surgery, and a Markov model was used for the analysis. Only direct medical costs were included in the analysis; indirect medical costs were excluded. Data were analyzed with TreeAge Pro 2015™ (TreeAge Software, Inc, Williamstown, MA, USA). RESULTS: Patients who underwent cervical anterior fusion had a total cost of KRW 2501807/USD 2357 over 5 years and obtained a utility of 3.72 QALY. Patients who underwent cervical artificial disc replacement received 4.18 QALY for a total of KRW 3685949/USD 3473 over 5 years. The cumulative cost-effectiveness ratio of cervical spine replacement surgery was KRW 2549511/QALY (USD 2402/QALY), which was lower than the general Korean payment standard. CONCLUSION: Both cervical anterior fusion and cervical artificial disc replacement are cost-effective treatments for patients with degenerative cervical disc disease. Cervical artificial disc replacement may be an effective alternative to obtain more benefits.

Disc replacement in lumbar spine / Artroplastia de disco na coluna lombar / Artroplastia de disco en la columna lumbar

ABSTRACT With the increase in the elderly population worldwide, the prevalence of degenerative diseases tends to grow, especially degenerative disc disease (DDD) in the lumbar spine. It is important to seek excellence treatments to ensure a better quality of life for patients. In this sense, the total disc replacement and the use of prostheses in the lumbar spine have been pointed out as alternative and promising treatments when compared to the standard treatment. The aim of this study is to show the results of total replacement of the intervertebral disc, through a review of the literature. The electronic search was performed in the PubMed databases, with the keywords "Total Disk Replacement", "Low Back Pain", and "Arthroplasty" in articles published as of 2012. We selected 16 articles. Level of Evidence: II. Type of study: Systematic reviewb of Level II studies or Level I studies with inconsistent results.

RESUMO Com o aumento da prevalência de idosos no mundo, a incidência de doenças degenerativas tende a crescer, especialmente a Doença degenerativa de disco (DDD) na coluna lombar. É importante buscar por tratamentos de excelência, para garantir melhor qualidade de vida aos pacientes. Nesse sentido, a substituição total do disco e o uso de próteses na coluna lombar tem sido apontados como tratamentos alternativos e promissores, quando comparado ao tratamento padrão. O objetivo deste artigo é mostrar os resultados da substituição total do disco intervertebral, por meio de uma revisão da literatura. Foi realizada a busca eletrônica nas bases de dados PubMed, a partir das palavras-chave: Substituição Total do Disco; Dor lombar; Artroplastia, publicados a partir de 2012. Foram selecionados um total de 16 artigos.Nível de Evidência: II. Tipo de estudo: Revisão sistemáticab de Estudos de nível II ou nível I com resultados discrepantes.

RESUMEN Con el aumento de la población de ancianos en todo el mundo, la prevalencia de enfermedades degenerativas tiende a crecer, especialmente la enfermedad degenerativa del disco (EDD) en la columna lumbar. Es importante buscar tratamientos de excelencia para garantizar una mejor calidad de vida a los pacientes. En este sentido, la sustitución del disco y el uso de prótesis en la columna lumbar han sido señalados como tratamientos alternativos y prometedores, en comparación con el tratamiento estándar. El objetivo de este estudio es mostrar los resultados de la sustitución total del disco intervertebral, por medio de una revisión de la literatura. Se realizó la búsqueda electrónica en las bases de datos PubMed, con los descriptores "Reemplazo total de disco", "Dolor lumbar", "Artroplastia", en artículos publicados a partir de 2012. Se seleccionaron 16 estudios. Nivel de Evidencia: II. Tipo de estudio: Revisión sistemáticab de Estudios de nivel II o nivel I con resultados discrepantes.

Rare Intractable Cervicalgia Related to Exaggerated Disc Height Distraction : Report of Two Cases and Literature Review

We present two cases of unexpected postoperative intractable cervicalgia due to over-sized implant insertion during simple anterior cervical decompression and fusion (ACDF) or artificial disc replacement (ADR). These patients experienced severe cervicalgia mostly related to their neck motion even after standard cervical operations. In both cases, the restored disc heights after the operations were prominently greater than the preoperative disc heights. The patients had not responded to any of the conservative treatments, and unloading of these excessively distracted segments through ultimate revision surgery led to dramatic pain relief. This report emphasizes the increase in distractional forces that takes place after a standard ACDF or ADR, as well as the importance of a proper sized implant. It also includes the reviews of other biomechanical or clinical reports dealing with this issue, thereby cautioning the surgeons not to disregard these factors, which might have an adverse effect in patients with cervicalgia even after radiographically successful cervical procedures.

Analysis of influence of shell angle of cervical artificial disc on long-term effectiveness of cervical artificial disc replacement / 中国修复重建外科杂志

Objective: To evaluate the influence of the shell angle of cervical artificial disc on long-term effectiveness of cervical artificial disc replacement (CADR). Methods: The clinical data of 71 patients who were treated with single-level CADR with Bryan prosthesis between December 2003 and December 2007 and followed up more than 10 years, were retrospectively analyzed. There were 44 males and 27 females with an age of 26-69 years (mean, 45.9 years). According to the shell angle of the cervical artificial disc which was measured on the postoperative lateral X-ray film, the patients were divided into kyphotic group (shell angle was negative) and non-kyphotic group. The following evaluation indexes before operation and at last follow-up were compared between 2 groups. Radiographic indexes included the range of motion (ROM) of cervical spine, the ROM of operated level, Cobb angle of operated level (the negative value indicated that the segmental kyphosis occurred at operated level), paravertebral ossification (PO) grades (grades 3 and 4 were high grade PO). Clinical indexes included Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), and overall effectiveness evaluation (Odom criteria). Results: There were 24 patients in kyphotic group and 47 patients in non-kyphotic group. There was no significant difference in baseline data including gender, age, and operated level between 2 groups ( P>0.05). All the patients in 2 groups were followed up 121-165 months (mean, 128 months). There was no significant difference in preoperative ROM of cervical spine and ROM of operated level between 2 groups ( P>0.05); but the preoperative Cobb angle of operated level in kyphosis group was significantly lower than that in non-kyphotic group ( t=2.636, P=0.013). There was no significant difference in ROM of cervical spine at last follow-up between 2 groups ( t=1.393, P=0.168), however, the ROM and the Cobb angle of operated level in kyphotic group were significantly lower than those in non-kyphotic group ( P0.05). Conclusion: The shell angle of cervical artificial disc may lead to a decrease in the postoperative segmental ROM, and an increased occurrence of segmental kyphosis and high incidence of PO.

Long-term clinical efficacy of cervical artificial disc replacement for cervical spondylotic radiculopathy / 中国修复重建外科杂志

Objective: To evaluate the long-term efficacy and influencing factors of cervical artificial disc replacement (CADR) for patients with cervical spondylotic radiculopathy (CSR). Methods: The data of 29 CSR patients who underwent Bryan artificial disc replacement between December 2003 and December 2007 and followed up more than 10 years were retrospectively analysed. There were 16 males and 13 females with an average age of 54.1 years (range, 40-70 years). The disease duration was 2-144 months (mean, 19.2 months). CT and MRI were performed before operation to identify the compression segments (C 3, 4 in 2 cases, C 4, 5 in 6 cases, C 5, 6 in 18 cases, C 6, 7 in 3 cases) and the compression factors. According to the compression factor, the patients were divided into 2 groups: 14 patients with cervical disc herniation were in the group A and 15 patients combined with osteophyte were in the group B. There was no significant difference in gender, age, disease duration, and compressed level between 2 groups ( P>0.05). The radiographic and clinical evaluation indexes were recorded before operation and at last follow-up. The radiographic evaluation indexes included the global cervical and segmental range of motion (ROM), loss of ROM (ROM0.05). Except that the loss of ROM (ROM0.05). The results of clinical evaluation indexes showed that the NDI was significantly improved in both groups ( P0.05). The excellent and good rate of overall efficacy reached 100% in both groups. Conclusion: CADR has satisfied long-term efficacy in treating CSR. The maintenance of segmental mobility was better in patients with disc herniation than in patients with disc herniation and osteophyte.

Progress of Finite Element Method Applied in Biomechanical Researches on Lumbar Fusion and Replacement / 医用生物力学

The research progress of finite element method (FEM) applied in biomechanics of lumbar fusion and artificial lumbar disc replacement was reviewed and its prospect was forecasted. The main research directions of FEM are optimal selection of operation plans before the surgery, performance evaluation of implanted devices and prediction of postoperative outcomes. Based on the recent research progress, the application prospects of FEM in simulation of personalized surgery, evaluation of elastic implants and postoperative prediction of novel operation method were discussed. By reviewing and prospecting the application of FEM in biomechanical research of lumbar fusion and artificial lumbar disc replacement, the purpose of this paper is to provide theoretical references and practical guidance for the treatment of lumbar diseases in clinic.

Are Controversial Issues in Cervical Total Disc Replacement Resolved or Unresolved?: A Review of Literature and Recent Updates

Since the launch of cervical total disc replacement (CTDR) in the early 2000s, many clinical studies have reported better outcomes of CTDR compared to those of anterior cervical discectomy and fusion. However, CTDR is still a new and innovative procedure with limited indications for clinical application in spinal surgery, particularly, for young patients presenting with soft disc herniation with radiculopathy and/or myelopathy. In addition, some controversial issues related to the assessment of clinical outcomes of CTDR remain unresolved. These issues, including surgical outcomes, adjacent segment degeneration (ASD), heterotopic ossification (HO), wear debris and tissue reaction, and multilevel total disc replacement (TDR) and hybrid surgeries are a common concern of spine surgeons and need to be resolved. Among them, the effect of CTDR on patient outcomes and ASD is theoretically and clinically important; however, this issue remains disputable. Additionally, HO, wear debris, multilevel TDR, and hybrid surgery tend to favor CTDR in terms of their effects on outcomes, but the potential of these factors for jeopardizing patients' safety postoperatively and/or to exert harmful effects on surgical outcomes in longer-term follow-up cannot be ignored. Consequently, it is too early to determine the therapeutic efficacy and cost-effectiveness of CTDR and will require considerable time and studies to provide appropriate answers regarding the same. For these reasons, CTDR requires longer-term follow-up data.

Risk factors of dysphagia after single-level anterior cervical surgery / 中华骨科杂志

Objective To explore the incidence of dysphagia and its potential risk factors.Methods From January 2014 to December 2015,a total of 187 patients who underwent single-level anterior cervical spine surgery were recruited in this retrospective analysis study.Specific perioperative data including age,gender,smoking,alcohol use,BMI,estimated blood loss,surgical segment,length of incision,and length of hospital stay were recorded respectively.The Bazaz grading system and the swallowing quality of life (SWAL-QOL) score were used to assess the presence and severity of dysphagia.According to the Bazaz grading system,the patients were divided into dysphagia group and non-dysphagia group 1 week after operation.One-factor x2 test and one-sample t test were used to univariate analyze the two groups of related factors,and select the potential variables for multivariate logistic regression analysis to identify the risk factors leading to dysphagia.Results The number of dysphagia patient was 99 (52.94％) at 1 week after surgery,and 16 (8.56％) at 1 year.The preoperative mean SWAL-QOL score was 65.62±4.41 points,which decreased to 58.72±7.54 points after surgery and rose up to 64.66±5.26 points at the 12-month follow-up.The SWAL-QOL score at 1 week after surgery was correlated with the operative time (r=-0.474;P ＜ 0.001).Multivariate analysis indicated that preoperative tracheal exercise (OR=0.302,95％CI:0.131,0.748),operation time ＜ 60 min (OR=0.407,95％CI:0.190,0.878),and arthroplasty (OR=0.211,95％CI:0.102,0.425) were the independent factors to reduce the incidence of postoperative dysphagia.Conclusion The incidence and severity of dysphagia symptoms after single-level anterior cervical spine surgery gradually decreased with the extension of follow-up time.Preoperative tracheal exercise,shortened operative time and manual artificial disc replacement may be helpful to reduce the postoperative occurrence of dysphagia.

Effect of Bryan cervical disc replacement on cervical curvature and replacement segment in treating cervical spondylosis / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the effect of Bryan cervical disc replacement on cervical curvature and replacement segment in the treatment of cervical spondylosis, and analyze its clinical efficacy.</p><p><b>METHODS</b>Forty-nine patients underwent Bryan artificial cervical disc replacement from August 2010 to August 2013 were retrospectively analyzed. There were 26 males and 23 females, aged from 27 to 66 years old with an average of 48.5 years. Including 21 cases of nerve root type, 16 cases of spinal cord type, 12 cases of mixed type. And 21 cases were single segment replacement, 28 cases were double segments replacement. Preoperative and postoperative pain was compared using visual analogue scale(VAS);cervical function was observed by Japanese Orthopedic Association Scores (JOA) and Neck Disability Index (NDI);cervical lordosis curvature, function spinal unit(FSU) curvature, activities of replacement and adjacent segment, FSU activity were measured by cervical X-rays. Clinical effects were evaluated by the Odom method.</p><p><b>RESULTS</b>All the patients were followed up for 18.5 to 37.3 months with an average of 33.1 months. Pvoperative VAS, JOA, NDI scores were 7.08±1.55, 5.2±1.9, 39.96±7.06 before operation, 3.76±2.33, 13.20±1.20, 25.20±6.64 at 3 months after operation, and 2.80±1.50, 14.3±1.6, 24.24±7.89 at the last follow-up. Patients at three months and the last follow-up after operation were obviously improved in their VAS, JOA, and NDI scores (<0.05). There was no significant difference between the scores at last follow-up and 3 months after operation. Cervical lordosis changed from (10.64±4.26)° preoperatively to (13.68±4.56) ° at the last follow-up;the FSU curvature from (5.40±0.41) °to (9.92±2.00) °at the last follow-up (<0.05). The range of motion of the cervical spine preoperatively, 3 month postoperatively, and at the last follow-up were(70.84±6.17)°, (60.00±6.58)°, (71.48±4.61)°; FSU activities were(12.00±0.49)°, (9.36±0.26)°, (12.52±0.33)°;the activities of replacement segment were (10.48±0.67)°, (7.24±0.34)°, (9.28±0.36)°;the activities of upper segment of replacement were (10.52±0.60)°, (8.60±0.30)°, (10.44±0.43)°;the activities of lower segment of replacement were (8.48±0.40)°, (6.56±0.36)°, (9.60±0.39)°;there were significant differences in above items preoperatively and 3 months postoperatively(<0.05); and there were no significant difference preoperatively and at the last follow-up(>0.05). Pharyngeal discomfort and hoarseness occurred in 5 cases, and were recovered within 2 weeks after operation;heterotopic ossification occurred in 1 case at 6 months after operation;displacement of prosthesis occurred in 1 case at 12 months after operation. Based on Odom standard to evaluate the clinical outcome, 20 cases obtained excellent results, with 27 good, 2 general.</p><p><b>CONCLUSIONS</b>Bryan artificial cervical disc replacement not only generate good clinical effects, but may also restore the cervical lordosis and FSU curvature, while retaining the activities of replacement segment, and restoring overall cervical biomechanical functions.</p>

Rare Intractable Cervicalgia Related to Exaggerated Disc Height Distraction : Report of Two Cases and Literature Review

We present two cases of unexpected postoperative intractable cervicalgia due to over-sized implant insertion during simple anterior cervical decompression and fusion (ACDF) or artificial disc replacement (ADR). These patients experienced severe cervicalgia mostly related to their neck motion even after standard cervical operations. In both cases, the restored disc heights after the operations were prominently greater than the preoperative disc heights. The patients had not responded to any of the conservative treatments, and unloading of these excessively distracted segments through ultimate revision surgery led to dramatic pain relief. This report emphasizes the increase in distractional forces that takes place after a standard ACDF or ADR, as well as the importance of a proper sized implant. It also includes the reviews of other biomechanical or clinical reports dealing with this issue, thereby cautioning the surgeons not to disregard these factors, which might have an adverse effect in patients with cervicalgia even after radiographically successful cervical procedures.

Radiographic Analysis of the Lumbosacral Juncture: Is There a Critical Sacral Angle for Total Disc Replacement?

STUDY DESIGN: Retrospective review of a patient cohort through a prospective study. PURPOSE: To determine whether there are correlations between radiographic measurements, including sacral slope (SS) and pelvic incidence (PI), and self-reported clinical outcomes among single-level L5/S1 ProDisc-L patients. OVERVIEW OF LITERATURE: The lumbosacral juncture presents unique biomechanical challenges with respect to artificial disc replacement (ADR) because of its orientation and consequential shear loading. Reports of inferior outcomes at L5/S1 compared to those of the outcomes at the levels above, including increased facet joint pain, suggest a relationship with the sacral inclination at L5/S1. METHODS: Plain standing lateral radiographs of 71 patients (age, 26–65 years) who underwent ADR at L5/S1 for degenerative disc disease were reviewed. SS and PI were measured based on pretreatment and initial follow-up standing films. Patient's average adjusted self assessments included the Oswestry disability index and visual analog scale for pain 2 years after ADR. Correlation coefficients were computed to evaluate relationships between radiographic parameters and clinical outcomes. Analysis of covariance was used to evaluate multivariate relationships among factors, including radiographic parameters, body mass index (BMI), and clinical outcomes. RESULTS: SS and PI values were obtained from 71 patients. The average SS was 33.3° and average PI was 39.9°. At the 24-month follow-up, no significant correlations (p≥0.05) were observed between radiographic parameters and clinical outcomes. BMI, age, and sex did not explain any variability in the relationships between clinical outcomes and SS and PI. CONCLUSIONS: We reviewed a large range of SS angles and found no associations between SS, PI, or BMI and clinical outcomes after ADR at L5/S1. These preliminary results demonstrate that ADR provided maintainence of pain relief and functional improvement for a wide range of SS angles, suggesting that steeper angles are not a contraindication for ADR.