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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.
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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.
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<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>
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Objective To study biomechanical properties such as range of motion (ROM), intervertebral disc stress, ligament tension of inferior cervical spinal segment after the treatment of Discover, Prodisc-C artificial intervertebral disc replacement, and anterior cervical discectomy and fusion (ACDF), as well as mechanical property changes of the prosthesis after implantation. Methods Three kinds of operation plan on C5-6 cervical disc degeneration were established: Discover model, Prodisc-C model and ACDF model, as well as C4-7 segment original model of cervical vertebra. Biomechanical property changes after operation in cervical spine C4-7 segment in sagittal, coronal and transverse section were analyzed. Results ROM changes of cervical segment C5-C6 were as following: in Discover model it increased by 12.7%-73.1%, Prodisc-C model increased by 74%-98%, ACDF decreased by 55.8%-71.8%. The stress of C4-5 intervertebral disc after Discover artificial disc replacement showed no obvious increase, while the stress of C6-7 intervertebral disc decreased by 33.2%-54.2% under flexion, extension and axial rotation conditions. The amplification of ligament tension in Discover model decreased by 30%-40% as compared to that in Prodisc-C model. The maximum stress of Discover model (36.72 MPa) appeared under flexion condition, which was smaller than that in Prodisc-C model. Conclusions Artificial disc replacement can help to keep movement performance for segment after surgery. As a newly developed artificial intervertebral disc prosthesis, Discover makes some progress in the aspect of decreasing ligament stress and maintaining spinal stability. The research findings will provide theoretical basis for the clinical study on ACDF and artificial cervical intervertebral disc replacement surgeries.
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We report two cases of cervical spinal epidural abscess (SEA), which are related to anterior cervical surgeries. The first case reveals a late postoperative infection without any predisposing factor. The second case reveals combined complication of infection and instrument failure (artificial disc). Both two cases manifested ascending infections that are unusual courses of anterior cervical infections. The abscess extended upwards and, finally, caused life threatening bacterial meningitis. We suggest aggressive surgical interventions with anti-bacterial therapies in such cases.
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Abscess , Diskectomy , Epidural Abscess , Meningitis , Meningitis, Bacterial , Spine , Total Disc ReplacementABSTRACT
Degenerative changes in the cervical spinal column are common in the adult population. Although most patients respond well to initial nonsurgical management, those who continue to have symptoms or patients with clinically evident myelopathy are candidates for surgical intervention. The objective of this article is to review and discuss the surgical treatment for degenerative cervical spine disease. Anterior cervical spine surgery is commonly used to treat numerous pathologic entities and is expected to increase with the development of surgical techniques and instruments. Autogenous tricortical iliac crest struts are the best option for anterior fusion, but they are associated with donor site morbidity. Equivalent fusion rates have been reported after allografting and autografting, combined with the use of anterior plates. Artificial disc replacement, one of the emerging motion-sparing technologies, is currently used and has shown excellent results. However, longer follow-up is needed to determine whether these devices can function well over time. Surgical treatments in degenerative cervical disease have shown excellent results. Appropriate methods that take into account the pathologic status of the patient and the surgeon's surgical experience can prevent complications and lead to excellent surgical outcomes.
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Adult , Humans , Radiculopathy , Spinal Cord Diseases , Spine , Tissue Donors , Total Disc Replacement , Transplantation, Autologous , Transplantation, HomologousABSTRACT
OBJECTIVE: Total intervertebral disc replacement is designed to preserve motion and avoid limitations of fusion after removing local pathology. The authors report the results of a signle-center study to determine functional and radi- ologic outcomes associated with cervical total disc replacement versus those of cervical fusion. METHODS: We retrospectively reviewed the charts and radiographs of patients who underwent a total intervertebral disc replacement(TDR) or a single-level anterior cervical fusion(ACDF) between January 1, 2004, and September 31, 2007. Clinical symptom was assessed using the Visual Analog Scale(VAS) of the neck and of the arm pain. Range of motion was determined by radiologic assessment of flexion-extension radiographs. Data were collected before surgery and at 6 weeks, 3, 6, 12, and 24 months after surgery. RESULT: A total of 125 patients were identified with 63 having TDR(43 males and 20 females) and 62 having fusion(42 males and 20 females). The average age was 49.1 years(TDR) and 51.7 years(ACDF)(p=0.229). The mean neck pain VAS before surgery was 6.52(TDR) and 6.61(ACDF)(p=0.732). At 2-year follow-up, the average neck pain VAS for the TDR group was 1.59 and ACDF 1.85(p=0.168). The mean arm pain VAS before surgery was 6.37(TDR) and 6.60(ACDF)(p=0.335). At 2 years: 1.41(TDR) and 1.65(ACDF)(P = 0.148). More motion(an average of 9.00 degrees at 24 months) was retained after surgery in the TDR group than the fusion group at the treatment level. There was no significant diffe- rence in motion at adjacent levels. CONCLUSION: Total disc replacement maintained physiological segmental motion at the 2-year follow-up. The finding that there was no statistically significant difference between the groups in motion at adjacent levels must be verified on further studies.
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Humans , Male , Arm , Biomechanical Phenomena , Follow-Up Studies , Intervertebral Disc , Neck , Neck Pain , Range of Motion, Articular , Retrospective Studies , Total Disc ReplacementABSTRACT
0.05).Measurement results of adjacent segment movement extention showed more significant changes in the fusion group than in the non-fusion group(P
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PURPOSE: To evaluate clinical outcomes of patients treated with artificial disc replacement (ADR) and to assess the capacity of this artificial disc replacement for preserving sagittal alignment and motion in the lumbar spine. MATERIALS AND METHODS: 24 patients (10 men and 14 women, with a mean age of 46.7 (range 37-65) years) who underwent ADR in one or two segments of lumbar spine and followed up more than 12 months (range, 12-23 months) were reviewed. The level of pain was evaluated using visual analog scale (VAS) for low back and gluteal pain and functional outcome was evaluated using Oswestry Disability Index (ODI). Sagittal alignment and mobility of the lumbar spine were assessed in standing radiographs and dynamic flexion-extension radiographs. RESULTS: The ODI improved from a mean of 33 (25-47) preoperatively to a mean of 11 (0-24) at the final follow-up. The VAS for lower back pain improved from 74 (50-100) to 23 (0-70) and for gluteal pain, the level improved from 52 (0-100) to 14 (0-60). The mean lordosis of the surgical segments was 16.7degrees preoperatively, 20.3degrees postoperatively, and 25.9degrees at final follow-up (p<0.05). The mean lordosis of the whole lumbar spine was 43.4degrees preoperatively, 36.9degrees postoperatively, and 49.4degrees at final follow-up (p<0.05). Range of motion of the operation segments was 13degrees preoperatively and 16.2degrees at the final follow-up, and that of the whole lumbar spine was 46.9degrees preoperatively and 48.1degrees at the final follow-up. CONCLUSION: These clinical results showed significantly less pain (VAS) and disability (ODI) after the ADR in the short term. In addition, the physiologic sagittal alignment and range of motion could be restored with ADR. The data from more patients and a longer follow-up will be needed to determine if these results can be maintained over the long term.
Subject(s)
Animals , Female , Humans , Male , Follow-Up Studies , Lordosis , Low Back Pain , Range of Motion, Articular , Spine , Total Disc Replacement , Visual Analog ScaleABSTRACT
Objectives To introduce a small incision of anterior extraperitoneal approach to the lumbar spine for single lumbar segment artificial disc replacement. Methods Nine patients suffered from single segment herniation of lumbar intervertebral disc underwent operation of artificial disc replacement. The approach of this operation was with a small incision through medial of left sheath of rectums and access to the retroperitoneal region through extraperitoneal appearance. The clinical and surgical data including the length of incision, length of operation, blood lose, effect and complication of operation were analyzed retrospectively in these 9 patients.Results The average length of incision,time of operation and blood lose was 6 7cm, 150 minutes and 335ml, respectively. The clinical evaluation scales (the 5-point Likert scales for pain, function, economic status, and medication usage) showed great improvement after operation of these patients(P=0 008). No serious complication related with the approach was found. Conclusions The a small anterior incision through peritoneum of left rectus abdominis sheath and access to the retroperitoneal region through extraperitoneal, which can expose the region of lumbar segment from L3 to S1 sufficiently, is a safe and mini-lesion approach for single lumbar segment artificial disc replacement.
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The current two most popular spine surgeries, discectomy and fusion, at best address the pathology of low back pain, but significantly change the normal structure and function of the disc and lead to further degeneration of the adjacent segments. Artificial disc replacement (ADR) is considered an alternative to fusion in treatment of the degenerative disc disease. It can restore the normal kinematic and load-shearing properties of diseased lumbar segments, maintaining stability and mobility with relief of pain. Over the past 40 years, a tremendous effort has been made to develop an artificial disc to replace the degenerated disc. Design criteria of artificial disc include endurance, biocompatibility, galvanic corrosion, geometry, constraints, dynamics, implant stability, and fail-safe. The indications of ADR are still not clear. But the principal indications include mono- and bi-segmental instability, the postnucleotomy syndrome, and spondylolisthesis up to Meyerding I after unsuccessful conservative treatment. The contra-indications are osteoporosis, previous or latent local infection, spondylolisthesis greater than Meyerding I, spinal stenosis, as well as degenerative spondylosis, mainly involving facet joints. There have been several reports about clinical results of ADR. The initial results seem to be good, but follow-up is too short for definite conclusions. Accurate patient selection is imperative to obtain good clinical results. Prospective and longer term studies are needed to evaluate the efficacy of ADR. The further development in designs and materials of artificial disc is the most important to duplicate not only the natural form of disc but also its function.