Objective To study the cl inical appl ication of Mobi-C prosthesis in treatment of anterior cervical discectomy and artificial disc replacement (ADR). Methods Between January 2009 and June 2009, 20 cases of degenerative cervical disease were treated with anterior discectomy and ADR by Mobi-C prosthesis, including 13 cases of cervical disc herniation and 7 cases of cervical spondylotic radiculopathy, and 25 Mobi-C prosthesis were implanted. There were 8 males and 12 females, aged 29-54 years (mean, 45.2 years). The disease duration was from 4 days to 5 years (mean, 1.2 years). Affected segments of process included C3, 4 in 1 case, C4, 5 in 2 cases, C5, 6 in 7 cases, C6, 7 in 5 cases, C4, 5 and C5, 6 in 2 cases, and C5, 6 and C6, 7 in 3 cases. Radiographs were taken regularly, and cervical range of motion (ROM) on segments of disc replacements were measured. The functions of cervical spinal cord were evaluated by “40 score” system (COA) preoperatively, immediately postoperatively, and at follow-up. The qual ity of l ife was evaluated by neck disabil ity index (NDI) and visual analogue scale (VAS) score. Results All incisions healed by first intention. No perioperative compl ication was found. All cases were followed up 16.5 months on average (range, 14-18 months). There was no significant difference in cervical ROM of operatied segment between preoperation and follow-up duration (t=0.808，P=0.440). No heterotopic ossification was found at follow-up. COA score at last follow-up (38.20 ± 1.14) was significantly higher than preoperative one (32.10 ± 2.96) , (t=9.278，P=0.000) , and the improvement rate at last follow-up was 77.2% ± 5.4%. VAS score at last follow-up (3.20 ± 1.23) had significant difference when compared with preoperative one (5.10 ± 1.29), (t=10.585，P=0.000). NDI score at last follow-up (29.40 ± 4.55) had significant difference when compared with preoperative one (39.20 ± 3.80), (t=16.039, P=0.000). Conclusion A satisfactory short-term curative effect can be obtained by using Mobi-C prosthesis in treatment of anterior cervical discectomy and ADR.
Objective To review the l iterature about the multiple level artificial disc replacement and investigate the prel iminary the cl inical outcome of the first case in China applying three-level PRESTIGE® LP artificial disc replacement for cervical disc degenerative disease. Methods In April 2009, one female patient aged 44 years old was treated. She was diagnosed as disc protrusion at the C4, 5, C5, 6, and C6, 7 level. She had paresthesia, decreased muscle strength and positivepathological reflex in her left upper extremity. The neck disabil ity index (NDI) was 43. The visual analogue scale (VAS) of the neck and the upper l imb was 6.6 and 8.1, respectively. SF-36 physical and psychological score was 28 and 36, respectively. The surgery was performed via routine anterior cervical approach. After complete decompression of three segments, prostheses were implanted from the cephal ic to the caudal end under radiographic monitoring. The patient was followed up 1 and 3 months after operation, respectively. Results The time of operation was 220 minutes and the blood loss during operation was 270 mL. The incision healed by first intention. There was no occurrence of compl ications such as aggravation of nerve symptoms, hoarse voice, difficult in swallow, and cerebrospinal fluid leakage. At 3 months after the operation, the patient had pain rel ief, muscle force recovery and improvement of l ife qual ity. X-ray films showed that the sequence of cervical vertebra was well-maintained, there was no loosening and displacement of prosthesis, and the position and function were good. NDI was decreased to 7, indicating that the l imitation was mild. The VAS of the neck and the upper l imb was 0.5 and 0.6, respectively. SF-36 physical and psychological score was 48 and 53, respectively. The result of operation was graded as excellent according to Odom’s criterion. The patient went back to her job. Conclusion Three-level PRESTIGE® LP artificial disc replacement for cervical disc degenerative disease has satisfactory prel iminary cl inical results. However, more cl inical case studies and longer cl inical followup are needed to confirm its therapeutic effect on multi-level disc disease.
Objective To explore the neck axial symptom (AS) after Bryan cervical disc arthroplasty traditional anterior cervical discectomy and fusion, and to make contrastive analysis. Methods From October 2004 to April 2006, 22 patients, 13 males and 9 females, aged 33-54 years old (43.3 on average), underwent Bryan cervical disc placement (groupA). Among them, there were 16 cases of cervical spondylotic myelopathy and 6 of nerve root cervical syndrome, with 20of single segment replacement and 2 of two segments replacement. The courses of disease were 1-21 months (6 months on average). Meanwhile, 30 patients, 17 males and 13 females, aged 35-64 years old (50.3 on average) underwent traditional anterior cervical discectomy and fusion (group B). Among them, there were 19 cases of cervical spondylotic myelopathy and 11 of nerve root cervical syndrome, with 26 of single segments replacement and 4 of two segments replacement. The course of disease was 1-23 months (7 months on average). In both groups, the neurologic recovery rate, the change of cervical curvature of the operated segments and total range of motion (ROM), and incidence of neck axial symptoms were recorded and compared. Results All the patients were followed up for 24-42 months (30.6 months on average). There was no graveness compl ication happening during and after operation in both groups. There were no compl ications of prosthesis bit shifting and amotio in group A, and group B exhibited a bony fusion on X-ray films 6 months after operation, without plate and bolt loose or broken. The patients’ cl inical symptoms of radiculopathy were obviously rel ieved and the curative effect was satisfactory in two groups of nerve root cervical syndrome. In both groups of cervical spondylotic myelopathy, the patients’ JOA scores at the postoperative follow-up increased obviously than preoperative (Plt; 0.01), and there was no significant difference between the two groups before the operation and at the end of the follow-up (P gt; 0.05). The rate of sagittal al ignment of the operated segment with kyphosis increased obviously in group B, higher than in group A (P lt; 0.05).The total ROM of group B was obviously lower than preoperative (Plt; 0.01), and the pre- and postoperative difference of group A was not statistically significant (P gt; 0.05). The rate of postoperative neck AS was 18.18% in group A and 46.67% in group B, and the difference was statistically significant(Plt; 0.05). Conclusion Compared with traditional anterior cervical discectomy and fusion, the use of Byran disc arthroplasty for cervical syndrome is associated with good outcomes. At the same time, it can maintain the cervical motion and curvature of operated segments, avoid the decrease of total ROM and lower the incidence of the postoperative neck AS.
Objective To evaluate the therapeutic effect ofthe two-level cervical artificial disc replacements combined with the nearby segments fused for the multi-level disc herniations and to investigate their interaction during the treatment. Methods The patient undergoing surgery was diagnosed as having intervertebral disc herniations in the C3-7 intervertebral discs. During the operation, the C4-6 discs were replaced with two Bryan artificial discs while the C3,4 and C6,7 discs were removed, followed by the bone grafting and the Zephir instrumentation. The range of motion (ROM) was assessed before and immediately after operation by the flexion-extension radiography. The patient’s functional exercise began as early as 2 days after operation and lasted for 3 weeks, followed by immobilization for 3 months. Results According to the follow-up for 1 year and 2 months, the patientcould move his neck in all directions without pain. The spinal and neural symptoms were significantly alleviated. ROM was close to the normal level postoperatively.Conclusion Artificial disc replacement combined with bone grafting and fusion is a new way to treat multilevel disc herniations surgically, with good clinical results. Early cervical functional exercise followed byrestriction is an effective way to deal with the contradiction of motion and immobilization.
Objective To explore the influence of discectomy and artificial disc replacement on the upper lumbar facet joint and to provide the evidence for use of artificial disc replacement. Methods Under the loads of 200-2 000 N axis pressure and 1-10 Nm back-extending/side-bending pressure on the 7 fresh adult corpses, the pressure of L3,4facet joint was measured in the case of L4,5disc integrity, discectomy and artificial disc replacement and the statistical analysis was done.ResultsUnder the same load (axis, back-extending/side bending), there were significant differences (Plt;0.01) in the pressure of upper lumbar facet jointboth between disc integrity and discectomy and between discectomy and artificial disc replacement, and there was no difference(Pgt;0.05) between disc integrity and artificial disc replacement. Conclusion The stress ofupper lumbar facet joint reduced after discectomy, it implies that simply discectomy may change biomechanics of lumbar and lead to secondary lumbar structure degeneration. The stress of upper lumbar facet joint is close to the normal value after artificial disc replancement, it implies that artificial disc replacement may protect lumbar structure. It provides some biomechanics foundation and evidence for artificial disc replacement.
Objective To evaluate the efficacy of artificial total disc replacement for lumbar degenerative disc disease compared with lumbar fusion and other treatment. Methods We conducted electronic searching on The Cochrane Library (Issue 2, 2004) and Specialized Trials Register of Cochrane Back Group, MEDLINE (1966 to 2004)，EMBASE (1980 to 2004) and CBMdisk (2003), some Chinese Journals were handsearched, and researchers in the field were contacted. Data were extracted and evaluated by two reviewers independently. The quality evaluation of studies and data analysis followed the methods of The Cochrane Collaboration. Results Three studies including 152 patients met the inclusion criteria. Two studies used ProDisc Ⅱ, while the other one used SB-Ⅲ. The patients who received the disc replacement reported reduced pain and improved function in early postoperative period, better satisfaction rates at month 6 post operation; complications of operation were reported in two randomized controlled trials. Conclusions The quality of the included trials is inadequate to draw any conclusion about the efficacy of artificial total disc replacement. More trials with high quality on methodology are needed. Artificial discs could preserve motion of diseased level in the short term. Protection of adjacent levels can only be assessed when large studies with long term follow-up are conducted.
【摘要】 目的 评价Bryan人工椎间盘单节段置换治疗颈椎间盘退变性疾病的临床疗效。 方法 2004年11月—2008年4月，21例颈椎间盘退变突出并经保守治疗无效的患者接受Bryan人工颈椎间盘单节段置换术。患者术前、术后1、6、12、18、24个月时使用颈椎功能障碍指数（neck disable index，NDI）、症状程度主观评价、疼痛视觉模拟疼痛量表（visual analogue scale，VAS）进行疗效评估，手术效果使用Odom法评价。影像学检查包括颈椎功能位X线片、颈椎CT及MRI检查。 结果 21例患者均顺利完成椎间盘置换手术，术后随访2年。患者对症状的主观评分，颈痛VAS评分、手臂疼痛VAS评分，NDI分别由术前的（2.80±0.42）、（4.62±1.84）、（5.01±1.79）、（22.60±4.88）分下降到随访终止时的（0.20±0.42）、（1.01±0.56）、（0.82±0.24）、（4.30±1.25）分。所有患者对手术效果Odom 评级优良，8例（38.1%）自觉症状完全缓解。手术过程平均时间为（110.5±42.6） min，术中出血量平均为（166.0±108.8） mL。影像学评价见植入的人工椎间盘运动功能良好，未见颈椎不稳的表现。2例假体在术后早期轻度前移。 结论 Bryan人工椎间盘单节段置换是治疗颈椎间盘退变性疾病的一种安全有效的方法，术后随访2年临床疗效满意。【Abstract】 Objective To evaluate the clinical therapeutic effect of single segment Bryan disc replacement on cervical disc degenerative diseases. Methods From November 2004 to April 2008, 21 patients who had a poor response after conservative treatment for their cervical disc degeneration underwent the single level Bryan disc replacement. Before the operation and 1, 6, 12, 18, and 24 months after the operation, all patients were evaluated by neck disable index (NDI), subjective symptom scale, visual analogue scale (VAS) and Odom score. The radiological examinations included X-ray, CT scan and MRI. Results Operations were successfully executed in 21 patients. All patients had obeyed the follow-up visiting at the expected time in the next two years after the operation. Patients′ symptom scale, VAS for neck pain, VAS for arm pain, NDI were 2.80±0.42, 4.62±1.84, 5.01±1.79, and 22.60±4.88, respectively before the operation and significantly decreased to 0.20±0.42, 1.01±0.56, 0.82±0.24, and 4.30±1.25, respectively at the end of the follow-up. All patients had good or higher score of the Odom score. The ymptoms were completely relieved in eight patients (38.1%). The mean operation time was (110.5±42.6) minutes, the average blood loss was (166.0±108.8) mL. The normal motion of the artificial disc was observed. No cervical instability was observed. Two prosthesis migrated slightly. Conclusion Single segmental Bryan disc replacement is safe and effective on the cervical disc degeneration. The two-year follow-up reveales a satisfied clinical outcome.
This study was aimed to estimate the effect of different ProDisc-C arthroplasty designs after it was implanted to C5-C6 cervicalspine. Finite element (FE) model of intact C5-C6 segments including the vertebrae and disc was developed and validated. Ball-and-socket artificial disc prosthesis model (ProDisc-C, Synthes) was implanted into the validated FE model and the curvature of the ProDisc-C prosthesis was varied. All models were loaded with compressed force 74 N and the pure moment of 1.8 Nm along flexion-extension and bilateral bending and axial torsion separately. The results indicated that the variation in the curvature of ball and socket configuration would influence the range of motion in flexion/extension, while there were not apparently differences under other conditions of loads. The method increasing the curvature will solve the stress concentration of the polyethylene, but it will also bring adverse outcomes, such as facet joint force increasing and ligament tension increasing. Therefore, the design of artificial discs should be considered comprehensively to reserve the range of motion as well as to avoid the adverse problems, so as not to affect the long-term clinical results.
The mechanical properties of artificial intervertebral disc (AID) are related to long-term reliability of prosthesis. There are three testing methods involved in the mechanical performance evaluation of AID based on different tools: the testing method using mechanical simulator, in vitro specimen testing method and finite element analysis method. In this study, the testing standard, testing equipment and materials of AID were firstly introduced. Then, the present status of AID static mechanical properties test (static axial compression, static axial compression-shear), dynamic mechanical properties test (dynamic axial compression, dynamic axial compression-shear), creep and stress relaxation test, device pushout test, core pushout test, subsidence test, etc. were focused on. The experimental techniques using in vitro specimen testing method and testing results of available artificial discs were summarized. The experimental methods and research status of finite element analysis were also summarized. Finally, the research trends of AID mechanical performance evaluation were forecasted. The simulator, load, dynamic cycle, motion mode, specimen and test standard would be important research fields in the future.
Objective To compare the short-term effectiveness and the impact on cervical segmental range of motion using Prodisc-C Vivo artificial disc replacement and Zero-P fusion for the treatment of single-segment cervical spondylosis. MethodsThe clinical data of 56 patients with single-segment cervical spondylosis who met the selection criteria between January 2015 and December 2018 were retrospectively analyzed, and they were divided into study group (27 cases, using Prodisc-C Vivo artificial disc replacement) and control group (29 cases, using Zero-P fusion) according to different surgical methods. There was no significant difference between the two groups in terms of gender, age, type of cervical spondylosis, disease duration, involved segments and preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), surgical segments range of motion, upper and lower adjacent segments range of motion, overall cervical spine range of motion, and cervical curvature (P>0.05). The operation time, intraoperative blood loss, postoperative hospitalization stay, time of returning to work, clinical effectiveness indicators (VAS score, JOA score, NDI, and improvement rate of each score), and imaging indicators (surgical segments range of motion, upper and lower adjacent segments range of motion, overall cervical spine range of motion, and cervical curvature, prosthesis position, bone absorption, heterotopic ossification, etc.) were recorded and compared between the two groups. ResultsThere was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05); the postoperative hospitalization stay and time of returning to work in the study group were significantly shorter than those in the control group (P<0.05). Both groups were followed up 12-64 months, with an average of 26 months. There was no complication such as limb or organ damage, implant failure, and severe degeneration of adjacent segments requiring reoperation. The VAS score, JOA score, and NDI of the two groups at each time point after operation significantly improved when compared with those before operation (P<0.05); there was no significant difference in the above scores at each time point after operation between the two groups (P>0.05); there was no significant difference in the improvement rate of each score between the two groups at last follow-up (P>0.05). The surgical segments range of motion in the study group maintained to varying degrees after operation, while it in the control group basically disappeared after operation, showing significant differences between the two groups (P<0.05). At last follow-up, there was no significant difference in the upper and lower adjacent segments range of motion in the study group when compared with preoperative ones (P>0.05), while the upper adjacent segments range of motion in the control group increased significantly (P<0.05). The overall cervical spine range of motion and cervical curvature of the two groups decreased at 3 months after operation, and increased to varying degrees at last follow-up, but there was no significant difference between groups and within groups (P>0.05). At last follow-up, X-ray films and CT examinations showed that no prosthesis loosening, subsidence, or displacement was found in all patients; there were 2 cases (7.4%) of periprosthetic bone resorption and 3 cases (11.1%) of heterotopic ossification which did not affect the surgical segments range of motion. ConclusionBoth the Prodisc-C Vivo artificial disc replacement and Zero-P fusion have satisfactory short-term effectiveness in treatment of single-segment cervical spondylosis. Prodisc-C Vivo artificial disc replacement can also maintain the cervical spine range of motion to a certain extent, while reducing the occurrence of excessive motion of adjacent segments after fusion.