Objective To study the effectiveness of artificial disc replacement for cervical diseases and the adjacent segment degeneration. Methods Between January 2008 and October 2010, 39 cases of cervical spondylosis underwent cervical disc replacement. Of them, there were 20 males and 19 females with an average age of 45.7 years (range, 32-60 years)and an average disease duration of 30 months (range, 1 month to 10 years), including 26 cases of cervical myelopathy, 11 cases of nerve root cervical spondylosis, and 2 cases of mixed cervical spondylosis. Single level disc lesion was observed in 27 cases while bi-level lesion in 12 cases. Prestige disc prosthesis was used in 9 patients, Prodisc-C prosthesis in 4 patients, and Discover disc prosthesis in 26 patients. The neurological functional recovery was assessed after operation by Japanese Orthopaedic Association (JOA) score. The range of motion of replaced segment and adjacent segments was measured (Cobb angle), and Kellgren’s X-ray assessment was used to evaluate the degree of adjacent segment degeneration. Results The operation was successfully performed in all cases, with primary heal ing of all the incisions. All patients were followed up from 12 to 36 months with an average of 23.1 months. JOA score was significantly improved at last follow-up when compared with preoperative score (P lt; 0.05), and no significant difference was observed in the Cobb angle of replaced segment and adjacent segments between pre- and postoperation (P gt; 0.05). According to the Kellgren’s X-ray assessment, degeneration of the adjacent segments occurred in 5 cases at last follow-up, including 3 cases of degeneration from grade 0 to grade 1 or 2, 1 from grade 1 to grade 2, and 1 from grade 2 to grade 3, with a degeneration rate of 12.8%, but no significant difference was found in degeneration degree when compared with preoperative value (χ2=1.793，P=0.406). No degeneration of adjacent segments occurred in 32 patients at 15 months after operation. Conclusion Artificial disc replacement has a good effectiveness in treating cervical spondylosis, which can maintain the range of motion of the replaced segment and adjacent segments, and may have a protective effect on adjacent segment discs.
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 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.