Cell Biochem Biophys (2015) 71:1077–1082 DOI 10.1007/s12013-014-0311-z
ORIGINAL PAPER
Comparison of Clinical Outcomes of Anterior Versus Posterior Surgery in Treating Multi-segmental Cervical Degeneration Qiang Wang • Jun Cai • Yuping Tao • Yu Sun • Xiaolei Li • Zhiqiang Zhang • Yongchao Fang • Jingcheng Wang
Published online: 21 October 2014 Ó Springer Science+Business Media New York 2014
Abstract The purpose of this study is to compare clinical outcome of different surgical methods in treating multisegmental cervical degeneration. Three hundred and sixty eight patients with multi-segmental cervical degeneration were retrospectively selected and divided into two groups with 184 cases in each based on different surgical methods: one group accepted surgeries from anterior surgical approach and the other group accepted surgeries from posterior surgical approach. Perioperative parameters including operative time, intraoperative blood loss and length of stay were compared between two groups. Patients were followed up after 1 week, 6 month, 10 months and 1 year after surgery. Cervical X-ray was retaken, and Japanese orthopaedic association (JOA) scores, neck disability index (NDI ) scores and numerical pain rating scale (NPRS ) scores were obtained for comparison. Samples from cervical disc were processed to detect cytokines level including IL-1, IL-6, TNF-a and MMP-3. Perioperative parameters including operative time, intraoperative blood loss and length of stay showed no significant difference (P \ 0.05) between the two groups. JOA score, NDI scores and NPRS scores, all showed a significant improvement after the surgery in both methods, however, when comparing the two methods, no significant difference was found between two groups (P [ 0.05), except that NDI scores in anterior surgical approach group were significantly lower than posterior surgical approach group at different follow-up time points (P \ 0.05). The average height of fused vertebral bodies after surgery in two groups
Q. Wang J. Cai Y. Tao Y. Sun X. Li Z. Zhang Y. Fang J. Wang (&) Department of Orthopaedics, Subei People’s Hospital, Yangzhou 225001, China e-mail: [email protected]
was significantly different from pre-operative height (P \ 0.05), and angle loss in posterior surgical approach group was significantly higher than anterior surgical approach (P \ 0.05), which was statistically different. Cytokines including IL-1, IL-6, TNF-a and MMP-3 in two groups had no statistical difference (P [ 0.05). Anterior approach surgery and posterior approach surgery are both effective methods to treat multi-segmental cervical degeneration. Anterior approach had better clinical outcomes within 1-year follow-up. Keywords Multi-segment Cervical degeneration disease Anterior approach surgery Posterior approach surgery
Introduction Multi-segmental cervical degeneration is the general name of a category of cervical diseases, which include cervical spondylosis of three or more continuous or intermittent segments, developmental spinal canal stenosis and ossification of posterior longitudinal ligaments (OPLL) etc. As the development of the ageing society, the prevalence of this disease is especially high in elderly population [1–3]. The aim of treating cervical degeneration disease is to decompress the spinal cord to avoid deterioration of neurological function and reestablish cervical stability. Rehabilitative measures are the first line choice, however, if all the none-operative measures proved to be ineffective, surgery should be considered. In patients with multi-segmental cervical degeneration, due to the severe condition and long involved segments, reestablishment of cervical stability and spinal cord decompression is more complicated than single-segmental cervical degeneration [4–6].
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At present, the commonly applied surgical methods including anterior approach, posterior approach and the combined approach, such as anterior vertebral resection arthrodesis, anterior cervical discectomy fusion, posterior vertebral lamina resection arthrodesis, posterior expansive open-door laminoplasty and multi-segmental artificial disc replacement and so on [7–10]. However, the optimal treatment for multi-segmental cervical degeneration remains controversial, and there’s constant debate over anterior versus posterior surgery. The purpose of this study is to compare clinical outcomes of the two surgical methods in treating multi-segmental cervical degeneration.
Methods Patient Information
Cell Biochem Biophys (2015) 71:1077–1082
vertebral plates were exposed to bilateral facet joints, bilateral vertebral plates were removed; 62 cases received Nakano operation method, notches were made at bilateral vertebral plates with one side of hinge and one side of open side. The perforation was made at spinous process, which was suspended to lateral paravertebral muscular fasciae; 30 patients received modified Nakano operation, the root of spinous process was cut off, which was perforated and move out to the margin of open side vertebral plate, and then fixed and infused; 34 cases received single-door expansive laminoplasty, paravertebral muscular fascia was peeled till the outer edge of zygopophysis, spinous process of C3–C7 were partly removed, the door was open from left, hinge was used for expansive laminoplasty at right side, notch located at 60° inner of zygopophysis, after opening the door, the remnant spinous process of C3–C7 were fixed to right semispinalis, and autologous spine bone was used for graft.
A total of 368 patients with multi-segmental degeneration were retrospectively selected from our hospital during March, 2012 to March, 2014. There were 213 male patients and 155 female patients with age average of 54.1 ± 3.8 (range 29–76). All patients were divided into two groups according to random number table method, including anterior approach surgery group and posterior approach surgery group with 184 cases in each group. The general data in two groups were comparable, with no statistical difference (P [ 0.05).
Post-operative Treatment
Surgical Methods
Evaluation of Clinical Outcome
Anterior Approach Surgery
Perioperative parameters including operative time, intraoperative blood loss and length of stay were recorded and compared between two groups. Patients were reexamined after 1 week, 6 month, 10 months and 1 year after surgery. Cervical X-ray was retaken; JOA scores, NDI scores and NPRS scores were obtained for comparison. Samples from cervical disc were processed to detect cytokines including IL-1, IL-6, TNF-a and MMP-3.
After surgery, all patients received antibiotics, dehydration and detumescence. Antibiotics were applied for 5 days, 20 % mannitol was used for dehydration, and 10 mg dexamethasone was applied for 3 days. After 48 h, the drainage tube was removed; after 4 days, patients started ambulation under the protection of neck collar, neck collar was used to protect the neck for 3 months without plaster external fixation.
Lateral incision on neck was selected to expose the diseased cervical segments. First, trephine method was used for vertebra corpectomy of most severe segment, and then the intervertebral disc in relatively less severe space had discectomy. 65 patients received anterior cervical decompression and cage internal fixation; 47 patients received anterior cervical decompression, autologous iliac crest graft and internal fixation with steel plate; 72 patients received anterior cervical decompression, internal fixation of steel plate and interbody fusion cage. The steel plates for long-segmental internal fixation started from anterior cervical vertebra approach, including Orion, Zephir and Codman steel plate. Orion steel plate was applied in 59 patients, Zephir steel plate was applied in 21 cases and Codman steel plate was applied in 39 cases.
Japanese orthopaedic association (JOA) score was used to evaluate cervical functioning and to calculate the recovery rate. The score is between 0 and 17, the lower the score the more severe the dysfunction. Recovery rate = (Post-operative total score-pre-operative total score)/(17-pre-operative total score) 9 100 %.
Posterior Approach Surgery
NDI Scoring Criteria
Median incision of neck was selected, 58 patients received complete laminectomy decompression. First, the bilateral
Neck disability index (NDI) score was used to evaluate cervical pain and cervical dysfunction. There are 10 items
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JOA Scoring Criteria
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in NID, the minimum score is 0 and the maximum score is 5 in every item. The higher the score, the more severe the dysfunction is. The cervical function injury rate = (The total score of all items/the items that objects completed 9 5) 9 100 %. The result is defined as slight dysfunction—‘‘0–20 %’’, medium dysfunction—‘‘20–40 %’’, severe dysfunction—‘‘40–60 %’’, profound dysfunction— ‘‘60–80 %’’, complete dysfunction—‘‘80–100 %’’.
Statistical Analysis SPSS17.0 was used for data analysis, numeration data were presented as x ± s. T test and ANOVA for repeated measurement were performed. P \ 0.05 was considered as statistically significant.
Results NPRS Scoring Criteria Numerical pain rating scale (NPRS) was used to evaluate the pain relief effect of the surgery. The score range is 0–10, where 0 represents no pain, 10 represent most severe pain. Radiographic Evaluation Cobb angular measurement method was used to measure the lateral curvature angle of spine. First, the upper and lower end vertebras were selected, which were the vertebra bodies with biggest lateral curvature angle. A transverse line was made at the bodies of upper vertebra and lower vertebra, the crossing angle of two lines was defined as Cobb angle. Cytokines Detection The vertebral disc was collected during the surgery; the disc was repeatedly washed with normal saline to remove the blood. The disc was placed in -80 °C ultra-low temperature refrigerator within 30 min. The intervertebral disc was weighted, and 1 ml 0.9 % NaCl solution was added in every 300 mg samples and then homogenized. The homogenate was centrifuged 3,000 r/min for 10 min at 4 °C to collect supernatant. ELISA was used to detect cytokines included IL-1, IL-6, TNF-a and MMP-3, according to the instruction of the kit.
Table 1 Comparison of perioperative parameters in two groups (x ± s)
Table 2 Comparison of JOA score and recovery rate in two groups before and after surgery
Group
Cases (n)
Comparison of Perioperative Parameters Between Two Groups Perioperative parameters including operative time, intraoperative blood loss and length of stay were compared between two groups (Table 1). The above parameters had no significant difference (P \ 0.05) between the two groups. Comparison of JOA Score and Recovery Rate in Two Groups Before and After Surgery Pre-operative and post-operative JOA scores are shown in Table 2. Both groups showed significant improvement after surgery, while there is no significant difference in post-operative JOA score and recovery rate between two groups (P [ 0.05). Comparison of NDI Score in Two Groups Before and After Surgery There is no significant difference of pre-operative NDI scores between the two groups (P [ 0.05). Both groups showed gradual improvement after the surgery, followed up at 1 week, 6 months, 10 months and 1 year. At all follow-up time points, NDI scores were significantly better in anterior surgical approach group compared with posterior surgical approach group (P \ 0.05), indicating that the recovery of cervical function in anterior surgical
Average operation time (min)
Average intraoperative blood loss (ml)
Average hospitalization time (d)
Anterior approach
184
135.88 ± 7.42
187.92 ± 23.65
17.51 ± 1.28
Posterior approach
184
142.33 ± 6.28
216.73 ± 24.87
16.34 ± 1.59
Group
Cases (n)
Pre-operative
Post-operative
Range
Range
Average
Recovery rate (%)
Average
Anterior approach
184
5–12
8.93 ± 1.24
9–17
14.25 ± 1.38
54.16 ± 7.54
Posterior approach
184
4–12
9.21 ± 1.27
8–18
14.87 ± 1.26
52.19 ± 6.38
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Table 3 Comparison of NDI scores before and after surgery in two groups (x ± s) Group
Cases (n)
Pre-operative
Post-operative 1 week
Anterior approach
184
24.8 ± 10.7
13.0 ± 6.3*
Posterior approach
184
22.4 ± 7.01
15.9 ± 3.9
*
Post-operative 6 months
Post-operative 10 months
Post-operative 1 year
7.4 ± 5.2*
7.2 ± 3.9*
7.8 ± 4.6*
12.3 ± 3.6
13.6 ± 3.7
12.6 ± 3.5
Represents P \ 0.05 compared with posterior surgical approach group at the same time point
Table 4 Comparison of NPRS scores before and after surgery in two groups (x ± s)
Table 5 Comparison of the average height of fused vertebral bodies before and after surgery in two groups (cm, x ± s)
Group
Cases (n)
Preoperative
Post-operative 1 week
Post-operative 6 months
Group
Cases (n)
Pre-operation
Post-operation
Anterior approach
184
7.29 ± 0.23
8.36 ± 0.18*
Anterior approach
184
6.18 ± 1.09
5.24 ± 0.87*
4.28 ± 0.92*
Posterior approach
184
7.18 ± 0.21
8.41 ± 0.19*
Posterior approach
184
6.56 ± 1.17
4.89 ± 0.092*
4.13 ± 1.07*
*
Represent P \ 0.05 compared with pre-operation score
*
Represent P \ 0.05 compared with pre-operation value
Comparison of Cytokine Expressions in Two Groups
approach group was better than posterior surgical approach group (Table 3).
Cytokine expressions of IL-1, IL-6, TNF-a and MMP-3 in both groups are shown in Table 7. No significant difference was found between two groups (P [ 0.05).
Comparison of NPRS Scores in Two Groups Before and After Surgery
Discussion
Pre-operative NPRS scores in anterior and posterior surgical approach group were 6.18 ± 1.09 and 6.56 ± 1.17, respectively. There was no significant difference between two groups (P [ 0.05). After the surgery, NPRS scores were significantly decreased in both groups (P \ 0.05), followed up at 1 week and 6 months. However, postoperative NPRS scores in two groups had no significant difference (P [ 0.05) (Table 4). Radiographic Evaluation Average height of fused vertebral bodies before and after surgery in two groups is shown in Table 5. The postoperative heights of fused vertebral bodies in two groups were significantly different from pre-operative values (P \ 0.05), the difference was statistically significant. However, the average height of fused vertebral bodies had no significant difference between two groups (P [ 0.05). Post-operative Cobb angles of fused vertebral bodies were different from pre-operative Cobb angles in two groups (P \ 0.05), which were statistically significant. The angular loss in anterior surgical approach group was (1.44 ± 0.44)° after 1 year and in posterior surgical approach group was (3.80 ± 0.36)° after 1 year, the angular loss in posterior surgical approach group was bigger than anterior surgical approach group (P \ 0.05), which was statistically different (Table 6).
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Multi-segmental cervical degeneration diseases mainly include posterior longitudinal ligament ossification and cervical spondylotic myelopathy, which often cause spasm, progressive paralysis, or even dysneuria [11, 12]. Multisegmental cervical degeneration disease often involves 2–4 vertebras between C3–C7, and can cause cervical instability, hyperostosis of ligaments and cervical vertebra, compression of the nerve root and spinal cord. Thus, nerve decompression is the key of treatment [13–15]. Any effective method should properly decompress, recover the physiological curvature of cervical vertebra and reestablish the stability of cervical vertebra. At present, the surgical treatments for multi-segmental degeneration disease include anterior approach surgery, posterior approach surgery and combined approach surgery. The anterior approach surgery can directly relieve the compression, effectively decompress to improve the functional recovery of cervical vertebra [16]. Besides, anterior approach surgery can be done at awake state under open view to prevent secondary injure. Posterior surgery is usually suitable for some diseases which are not fit for anterior approach surgery such as thickening of ligamentum flavum, developmental spinal canal stenosis, OPLL and multi-segmental cervical spondylotic myelopathy complicated with OPLL [17, 18]. In recent years, as the development of cervical vertebral surgery, many new surgical techniques have been applied
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Table 6 Comparison of Cobb angle of fused vertebral bodies before and after surgery in two groups (°, x ± s) Group
Cases (n)
Pre-operative
Post-operative 1 week
Post-operative 6 months
Post-operative 1 year
Angle loss post-operative 1 year
Anterior approach
184
1.93 ± 0.12
8.69 ± 0.82
8.14 ± 0.51
7.25 ± 0.38
1.44 ± 0.44*
Posterior approach
184
1.86 ± 0.14
8.83 ± 0.25
7.94 ± 0.52
5.03 ± 0.61
3.80 ± 0.36
*
Represent P \ 0.05 compared with posterior surgical approach group
Table 7 Comparison of cytokine expressions in two groups
Group
Cases (n)
IL-1 (ng/L)
IL-6 (pg/mL)
TNF-a (ng/mL)
MMP-3 (lg/L)
Anterior approach
184
5.49 ± 1.38
29.35 ± 8.24
0.48 ± 0.19
0.43 ± 0.09
Posterior approach
184
5.18 ± 1.24
32.11 ± 8.06
0.51 ± 0.17
0.37 ± 0.11
and new biomaterials have appeared. Despite various options available, the decision to use either an anterior or a posterior approach and the choice of specific procedure is constantly under the debate in clinical settings. In this study, we compared the clinical outcomes of the two methods in treating multi-segmental cervical degeneration hoping to provide some evidence for clinical decisionmaking. Our study showed that perioperative parameters including operative time, intraoperative blood loss and length of stay showed no difference between the two groups. JOA score, NDI scores and NPRS scores all showed a significant improvement after the surgery in both groups; however, when comparing the two methods, only NDI scores showed a better improvement in anterior group compared with posterior group at different follow-up time points, while the rest of the scores did not show any difference between the two groups. Radiographic outcomes showed that the average height of fused vertebral bodies after surgery in two groups was significantly different from pre-operative height, and angle loss in posterior surgical approach group was significantly higher than anterior surgical approach. Cytokines including IL-1, IL-6, TNF-a and MMP-3 in two groups had no statistical difference. Our study suggested that both anterior and posterior method provide effective treatment for multi-segmental cervical degeneration. Compared with posterior approach, anterior method achieved a better clinical outcome during the 1-year follow-up. Other researchers have done the similar comparative studies on the two methods [19–26], and the results are controversial. A recent meta-analysis reported that for multi-segmental cervical disease patients, the final followup JOA score for the anterior group was significantly higher than the posterior group in the ‘follow-up time B5 years’ subgroup, but had no significant differences in the ‘follow-up time [5 years’ subgroup [27]. The recovery rate for the anterior group was also significantly higher
than the posterior group in the ‘follow-up time B5 years’ subgroup. Although JOA scores and recovery rate in our study did not show any difference between the two groups within 1-year follow-up, the overall data, especially NDI scores and radiographic results from our study are in consistent with the meta-analysis. Recent research about the biochemical mechanism of cervical degeneration and the effect on neurological function showed that cytokines play important role in the pathology of cervical degeneration [28, 29]. IL-1, IL-6, TNF-a and MMP-3 are proven to be closely related to cervical degeneration diseases [30–33]. In this study, no difference of cytokine level was found between the two groups suggesting the similar degree of cervical degeneration. In conclusion, anterior approach surgery and posteriors approach surgery are both effective methods to treat multisegmental cervical degeneration, and anterior approach had better clinical outcomes within 1-year follow-up. References 1. Jawahar, A., Cavanaugh, D. A., Kerr, E. J, I. I. I., et al. (2010). Total disc arthroplasty does not affect the incidence of adjacent segment degeneration in cervical spine: results of 93 patients in three prospective randomized clinical trials. The Spine Journal, 10(12), 1043–1048. 2. Yang, B., Li, H., Zhang, T., et al. (2012). The incidence of adjacent segment degeneration after cervical disc arthroplasty (CDA): A meta analysis of randomized controlled trials. PLoS One, 7(4), e35032. 3. Hussain, M., Natarajan, R. N., An, H. S., et al. (2012). Progressive disc degeneration at C5–C6 segment affects the mechanics between disc heights and posterior facets above and below the degenerated segment: A flexion–extension investigation using a poroelastic C3–T1 finite element model. Medical Engineering & Physics, 34(5), 552–558. 4. Nunley, P. D., Jawahar, A., Kerr, E. J., et al. (2012). Factors affecting the incidence of symptomatic adjacent-level disease in cervical spine after total disc arthroplasty: 2- to 4-year follow-up of 3 prospective randomized trials. Spine, 37(6), 445–451.
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1082 5. Nunley, P. D., Jawahar, A., Cavanaugh, D. A., et al. (2013). Symptomatic adjacent segment disease after cervical total disc replacement: Re-examining the clinical and radiological evidence with established criteria. The Spine Journal, 13(1), 5–12. 6. Zigler, J. E., Delamarter, R., Murrey, D., et al. (2013). ProDisc-C and anterior cervical discectomy and fusion as surgical treatment for single-level cervical symptomatic degenerative disc disease: 5-year results of a Food and Drug Administration study. Spine, 38(3), 203–209. 7. Davis, R. J., Kim, K. D., Hisey, M. S., et al. (2013). Cervical total disc replacement with the Mobi-C cervical artificial disc compared with anterior discectomy and fusion for treatment of 2-level symptomatic degenerative disc disease: A prospective, randomized, controlled multicenter clinical trial: clinical article. Journal of Neurosurgery, 19(5), 532–545. 8. Kelly, M. P., Mok, J. M., Frisch, R. F., et al. (2011). Adjacent segment motion after anterior cervical discectomy and fusion versus Prodisc-c cervical total disk arthroplasty: analysis from a randomized, controlled trial[J]. Spine, 36(15), 1171–1179. 9. Kikkawa, J., Cunningham, B. W., Shirado, O., et al. (2010). Multidirectional flexibility of the spine following posterior decompressive surgery after single-level cervical disc arthroplasty: An in vitro biomechanical investigation. Spine, 35(25), E1465– E1471. 10. McCormack, B. M., Bundoc, R. C., Ver, M. R., et al. (2013). Percutaneous posterior cervical fusion with the DTRAX Facet System for single-level radiculopathy: Results in 60 patients: Clinical article. Journal of Neurosurgery, 18(3), 245–254. 11. Bydon, M., Xu, R., De la Garza-Ramos, R., et al. (2014). Adjacent segment disease after anterior cervical discectomy and fusion: Incidence and clinical outcomes of patients requiring anterior versus posterior repeat cervical fusion. Surgical Neurology International, 5(Suppl 3), S74. 12. Lundine, K. M., Davis, G., Rogers, M., et al. (2014). Prevalence of adjacent segment disc degeneration in patients undergoing anterior cervical discectomy and fusion based on pre-operative MRI findings. Journal of Clinical Neuroscience, 21(1), 82–85. 13. Guzman, J. Z., Baird, E. O., Fields, A. C., et al. (2014). C5 nerve root palsy following decompression of the cervical spine a systematic evaluation of the literature. Bone & Joint Journal, 96(7), 950–955. ¨ berg, B., Wibault, J., et al. (2014). Outcome of 14. Peolsson, A., O physiotherapy after surgery for cervical disc disease: a prospective randomised multi-centre trial. BMC Musculoskeletal Disorders, 15(1), 34. 15. Saarinen, T., Niemela¨, M., Kivisaari, R., et al. (2013). Early and late re-operations after anterior cervical decompression and fusion during an 11-year follow-up. Acta Neurochirurgica, 155(2), 285–291. 16. Caruso, R., Pesce, A., Marrocco, L., et al. (2014). Anterior approach to the cervical spine for treatment of spondylosis or disc herniation: Long-term results. Comparison between ACD, ACDF, TDR. Clinica Terapeutica, 165(4), e263–e270. 17. Seng, C., Tow, B. P. B., Siddiqui, M. A., et al. (2013). Surgically treated cervical myelopathy: a functional outcome comparison study between multilevel anterior cervical decompression fusion with instrumentation and posterior laminoplasty. The Spine Journal, 13(7), 723–731. 18. Xu, R., Bydon, M., Macki, M., et al. (2014). Adjacent segment disease after anterior Cervical Discectomy and Fusion: Clinical Outcomes After First Repeat Surgery Versus Second Repeat Surgery[J]. Spine, 39(2), 120–126.
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Cell Biochem Biophys (2015) 71:1077–1082 19. Yonenobu K, Hosono N, Iwasaki M, et al (1992) Laminoplasty versus subtotal corpectomy. A comparative study of results in multisegmental cervical spondylotic myelopathy. Spine 1281–1284. 20. Hirabayashi, K., & Bohlman, H. H. (1995). Controversy multilevel cervical spondylosis: laminoplasty versus anterior decompression. Spine., 20, 1732–1734. 21. Wada, E., Suzuki, S., Kanazawa, A., et al. (2001). Subtotal corpectomy versus laminoplasty for multilevel cervical spondylotic myelopathy: a long-term follow-up study over 10 years. Spine., 26, 1443–1448. 22. Tani, T., Ushida, T., Ishida, K., et al. (2002). Relative safety of anterior microsurgical decompression versus laminoplasty for cervical myelopathy with a massive ossified posterior longitudinal ligament. Spine., 27, 2491–2498. 23. Edwards, C. C., Heller, J. G., & Murakami, H. (2002). Corpectomy versus laminoplasty for multilevel cervical myelopathy: an independent matched-cohort analysis. Spine., 27, 1168–1175. 24. Iwasaki, M., Okuda, S., & Miyauchi, A. (2007). Surgical strategy for cervical myelopathy due to ossification of the posterior longitudinal ligament. Part 2: advantages of anterior decompression and fusion over laminoplasty. Spine., 32, 654–660. 25. Lee, S. H., Ahn, Y., & Lee, J. H. (2008). Laser-assisted anterior cervical corpectomy versus posterior laminoplasty for cervical myelopathic patients with multilevel ossification of the posterior longitudinal ligament. Photomed Laser Surg., 26, 119–127. 26. Kristof, R. A., Kiefer, T., Thudium, M., et al. (2009). Comparison of ventral corpectomy and plate-screw-instrumented fusion with dorsal laminectomy and rod-screw-instrumented fusion for treatment of at least two vertebral-level spondylotic cervical myelopathy. European Spine Journal, 18, 1951–1956. 27. Liu, T., Xu, W., Cheng, T., & Yang, H. L. (2011). Anterior versus posterior surgery for multilevel cervical myelopathy, which one is better? A systematic review. European Spine Journal, 20(2), 224–235. 28. Kim, J. S., Ellman, M. B., Yan, D., et al. (2013). Lactoferricin mediates anti-inflammatory and anti-catabolic effects via inhibition of IL-1 and LPS activity in the intervertebral disc. Journal of Cellular Physiology, 228(9), 1884–1896. 29. Furtwa¨ngler, T., Chan, S. C. W., Bahrenberg, G., et al. (2013). Assessment of the matrix degenerative effects of MMP-3, ADAMTS-4, and HTRA1, injected into a bovine intervertebral disc organ culture model. Spine, 38(22), E1377–E1387. 30. Alimasi, W., Sawaji, Y., Endo, K., et al. (2013). Regulation of nerve growth factor by anti-inflammatory drugs, a steroid, and a selective cyclooxygenase 2 inhibitor in human intervertebral disc cells stimulated with interleukin-1. Spine, 38(17), 1466–1472. 31. Phillips, K. L. E., Chiverton, N., Michael, A. L. R., et al. (2013). The cytokine and chemokine expression profile of nucleus pulposus cells: implications for degeneration and regeneration of the intervertebral disc. Arthritis Research & Therapy, 15(6), R213. 32. Purmessur, D., Walter, B. A., Roughley, P. J., et al. (2013). A role for TNFa in intervertebral disc degeneration: a non-recoverable catabolic shift. Biochemical and Biophysical Research Communications, 433(1), 151–156. 33. Quero, L., Klawitter, M., Schmaus, A., et al. (2013). Hyaluronic acid fragments enhance the inflammatory and catabolic response in human intervertebral disc cells through modulation of toll-like receptor 2 signalling pathways. Arthritis Research & Therapy, 15(4), R94.
ORIGINAL PAPER
Comparison of Clinical Outcomes of Anterior Versus Posterior Surgery in Treating Multi-segmental Cervical Degeneration Qiang Wang • Jun Cai • Yuping Tao • Yu Sun • Xiaolei Li • Zhiqiang Zhang • Yongchao Fang • Jingcheng Wang
Published online: 21 October 2014 Ó Springer Science+Business Media New York 2014
Abstract The purpose of this study is to compare clinical outcome of different surgical methods in treating multisegmental cervical degeneration. Three hundred and sixty eight patients with multi-segmental cervical degeneration were retrospectively selected and divided into two groups with 184 cases in each based on different surgical methods: one group accepted surgeries from anterior surgical approach and the other group accepted surgeries from posterior surgical approach. Perioperative parameters including operative time, intraoperative blood loss and length of stay were compared between two groups. Patients were followed up after 1 week, 6 month, 10 months and 1 year after surgery. Cervical X-ray was retaken, and Japanese orthopaedic association (JOA) scores, neck disability index (NDI ) scores and numerical pain rating scale (NPRS ) scores were obtained for comparison. Samples from cervical disc were processed to detect cytokines level including IL-1, IL-6, TNF-a and MMP-3. Perioperative parameters including operative time, intraoperative blood loss and length of stay showed no significant difference (P \ 0.05) between the two groups. JOA score, NDI scores and NPRS scores, all showed a significant improvement after the surgery in both methods, however, when comparing the two methods, no significant difference was found between two groups (P [ 0.05), except that NDI scores in anterior surgical approach group were significantly lower than posterior surgical approach group at different follow-up time points (P \ 0.05). The average height of fused vertebral bodies after surgery in two groups
Q. Wang J. Cai Y. Tao Y. Sun X. Li Z. Zhang Y. Fang J. Wang (&) Department of Orthopaedics, Subei People’s Hospital, Yangzhou 225001, China e-mail: [email protected]
was significantly different from pre-operative height (P \ 0.05), and angle loss in posterior surgical approach group was significantly higher than anterior surgical approach (P \ 0.05), which was statistically different. Cytokines including IL-1, IL-6, TNF-a and MMP-3 in two groups had no statistical difference (P [ 0.05). Anterior approach surgery and posterior approach surgery are both effective methods to treat multi-segmental cervical degeneration. Anterior approach had better clinical outcomes within 1-year follow-up. Keywords Multi-segment Cervical degeneration disease Anterior approach surgery Posterior approach surgery
Introduction Multi-segmental cervical degeneration is the general name of a category of cervical diseases, which include cervical spondylosis of three or more continuous or intermittent segments, developmental spinal canal stenosis and ossification of posterior longitudinal ligaments (OPLL) etc. As the development of the ageing society, the prevalence of this disease is especially high in elderly population [1–3]. The aim of treating cervical degeneration disease is to decompress the spinal cord to avoid deterioration of neurological function and reestablish cervical stability. Rehabilitative measures are the first line choice, however, if all the none-operative measures proved to be ineffective, surgery should be considered. In patients with multi-segmental cervical degeneration, due to the severe condition and long involved segments, reestablishment of cervical stability and spinal cord decompression is more complicated than single-segmental cervical degeneration [4–6].
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At present, the commonly applied surgical methods including anterior approach, posterior approach and the combined approach, such as anterior vertebral resection arthrodesis, anterior cervical discectomy fusion, posterior vertebral lamina resection arthrodesis, posterior expansive open-door laminoplasty and multi-segmental artificial disc replacement and so on [7–10]. However, the optimal treatment for multi-segmental cervical degeneration remains controversial, and there’s constant debate over anterior versus posterior surgery. The purpose of this study is to compare clinical outcomes of the two surgical methods in treating multi-segmental cervical degeneration.
Methods Patient Information
Cell Biochem Biophys (2015) 71:1077–1082
vertebral plates were exposed to bilateral facet joints, bilateral vertebral plates were removed; 62 cases received Nakano operation method, notches were made at bilateral vertebral plates with one side of hinge and one side of open side. The perforation was made at spinous process, which was suspended to lateral paravertebral muscular fasciae; 30 patients received modified Nakano operation, the root of spinous process was cut off, which was perforated and move out to the margin of open side vertebral plate, and then fixed and infused; 34 cases received single-door expansive laminoplasty, paravertebral muscular fascia was peeled till the outer edge of zygopophysis, spinous process of C3–C7 were partly removed, the door was open from left, hinge was used for expansive laminoplasty at right side, notch located at 60° inner of zygopophysis, after opening the door, the remnant spinous process of C3–C7 were fixed to right semispinalis, and autologous spine bone was used for graft.
A total of 368 patients with multi-segmental degeneration were retrospectively selected from our hospital during March, 2012 to March, 2014. There were 213 male patients and 155 female patients with age average of 54.1 ± 3.8 (range 29–76). All patients were divided into two groups according to random number table method, including anterior approach surgery group and posterior approach surgery group with 184 cases in each group. The general data in two groups were comparable, with no statistical difference (P [ 0.05).
Post-operative Treatment
Surgical Methods
Evaluation of Clinical Outcome
Anterior Approach Surgery
Perioperative parameters including operative time, intraoperative blood loss and length of stay were recorded and compared between two groups. Patients were reexamined after 1 week, 6 month, 10 months and 1 year after surgery. Cervical X-ray was retaken; JOA scores, NDI scores and NPRS scores were obtained for comparison. Samples from cervical disc were processed to detect cytokines including IL-1, IL-6, TNF-a and MMP-3.
After surgery, all patients received antibiotics, dehydration and detumescence. Antibiotics were applied for 5 days, 20 % mannitol was used for dehydration, and 10 mg dexamethasone was applied for 3 days. After 48 h, the drainage tube was removed; after 4 days, patients started ambulation under the protection of neck collar, neck collar was used to protect the neck for 3 months without plaster external fixation.
Lateral incision on neck was selected to expose the diseased cervical segments. First, trephine method was used for vertebra corpectomy of most severe segment, and then the intervertebral disc in relatively less severe space had discectomy. 65 patients received anterior cervical decompression and cage internal fixation; 47 patients received anterior cervical decompression, autologous iliac crest graft and internal fixation with steel plate; 72 patients received anterior cervical decompression, internal fixation of steel plate and interbody fusion cage. The steel plates for long-segmental internal fixation started from anterior cervical vertebra approach, including Orion, Zephir and Codman steel plate. Orion steel plate was applied in 59 patients, Zephir steel plate was applied in 21 cases and Codman steel plate was applied in 39 cases.
Japanese orthopaedic association (JOA) score was used to evaluate cervical functioning and to calculate the recovery rate. The score is between 0 and 17, the lower the score the more severe the dysfunction. Recovery rate = (Post-operative total score-pre-operative total score)/(17-pre-operative total score) 9 100 %.
Posterior Approach Surgery
NDI Scoring Criteria
Median incision of neck was selected, 58 patients received complete laminectomy decompression. First, the bilateral
Neck disability index (NDI) score was used to evaluate cervical pain and cervical dysfunction. There are 10 items
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JOA Scoring Criteria
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in NID, the minimum score is 0 and the maximum score is 5 in every item. The higher the score, the more severe the dysfunction is. The cervical function injury rate = (The total score of all items/the items that objects completed 9 5) 9 100 %. The result is defined as slight dysfunction—‘‘0–20 %’’, medium dysfunction—‘‘20–40 %’’, severe dysfunction—‘‘40–60 %’’, profound dysfunction— ‘‘60–80 %’’, complete dysfunction—‘‘80–100 %’’.
Statistical Analysis SPSS17.0 was used for data analysis, numeration data were presented as x ± s. T test and ANOVA for repeated measurement were performed. P \ 0.05 was considered as statistically significant.
Results NPRS Scoring Criteria Numerical pain rating scale (NPRS) was used to evaluate the pain relief effect of the surgery. The score range is 0–10, where 0 represents no pain, 10 represent most severe pain. Radiographic Evaluation Cobb angular measurement method was used to measure the lateral curvature angle of spine. First, the upper and lower end vertebras were selected, which were the vertebra bodies with biggest lateral curvature angle. A transverse line was made at the bodies of upper vertebra and lower vertebra, the crossing angle of two lines was defined as Cobb angle. Cytokines Detection The vertebral disc was collected during the surgery; the disc was repeatedly washed with normal saline to remove the blood. The disc was placed in -80 °C ultra-low temperature refrigerator within 30 min. The intervertebral disc was weighted, and 1 ml 0.9 % NaCl solution was added in every 300 mg samples and then homogenized. The homogenate was centrifuged 3,000 r/min for 10 min at 4 °C to collect supernatant. ELISA was used to detect cytokines included IL-1, IL-6, TNF-a and MMP-3, according to the instruction of the kit.
Table 1 Comparison of perioperative parameters in two groups (x ± s)
Table 2 Comparison of JOA score and recovery rate in two groups before and after surgery
Group
Cases (n)
Comparison of Perioperative Parameters Between Two Groups Perioperative parameters including operative time, intraoperative blood loss and length of stay were compared between two groups (Table 1). The above parameters had no significant difference (P \ 0.05) between the two groups. Comparison of JOA Score and Recovery Rate in Two Groups Before and After Surgery Pre-operative and post-operative JOA scores are shown in Table 2. Both groups showed significant improvement after surgery, while there is no significant difference in post-operative JOA score and recovery rate between two groups (P [ 0.05). Comparison of NDI Score in Two Groups Before and After Surgery There is no significant difference of pre-operative NDI scores between the two groups (P [ 0.05). Both groups showed gradual improvement after the surgery, followed up at 1 week, 6 months, 10 months and 1 year. At all follow-up time points, NDI scores were significantly better in anterior surgical approach group compared with posterior surgical approach group (P \ 0.05), indicating that the recovery of cervical function in anterior surgical
Average operation time (min)
Average intraoperative blood loss (ml)
Average hospitalization time (d)
Anterior approach
184
135.88 ± 7.42
187.92 ± 23.65
17.51 ± 1.28
Posterior approach
184
142.33 ± 6.28
216.73 ± 24.87
16.34 ± 1.59
Group
Cases (n)
Pre-operative
Post-operative
Range
Range
Average
Recovery rate (%)
Average
Anterior approach
184
5–12
8.93 ± 1.24
9–17
14.25 ± 1.38
54.16 ± 7.54
Posterior approach
184
4–12
9.21 ± 1.27
8–18
14.87 ± 1.26
52.19 ± 6.38
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Table 3 Comparison of NDI scores before and after surgery in two groups (x ± s) Group
Cases (n)
Pre-operative
Post-operative 1 week
Anterior approach
184
24.8 ± 10.7
13.0 ± 6.3*
Posterior approach
184
22.4 ± 7.01
15.9 ± 3.9
*
Post-operative 6 months
Post-operative 10 months
Post-operative 1 year
7.4 ± 5.2*
7.2 ± 3.9*
7.8 ± 4.6*
12.3 ± 3.6
13.6 ± 3.7
12.6 ± 3.5
Represents P \ 0.05 compared with posterior surgical approach group at the same time point
Table 4 Comparison of NPRS scores before and after surgery in two groups (x ± s)
Table 5 Comparison of the average height of fused vertebral bodies before and after surgery in two groups (cm, x ± s)
Group
Cases (n)
Preoperative
Post-operative 1 week
Post-operative 6 months
Group
Cases (n)
Pre-operation
Post-operation
Anterior approach
184
7.29 ± 0.23
8.36 ± 0.18*
Anterior approach
184
6.18 ± 1.09
5.24 ± 0.87*
4.28 ± 0.92*
Posterior approach
184
7.18 ± 0.21
8.41 ± 0.19*
Posterior approach
184
6.56 ± 1.17
4.89 ± 0.092*
4.13 ± 1.07*
*
Represent P \ 0.05 compared with pre-operation score
*
Represent P \ 0.05 compared with pre-operation value
Comparison of Cytokine Expressions in Two Groups
approach group was better than posterior surgical approach group (Table 3).
Cytokine expressions of IL-1, IL-6, TNF-a and MMP-3 in both groups are shown in Table 7. No significant difference was found between two groups (P [ 0.05).
Comparison of NPRS Scores in Two Groups Before and After Surgery
Discussion
Pre-operative NPRS scores in anterior and posterior surgical approach group were 6.18 ± 1.09 and 6.56 ± 1.17, respectively. There was no significant difference between two groups (P [ 0.05). After the surgery, NPRS scores were significantly decreased in both groups (P \ 0.05), followed up at 1 week and 6 months. However, postoperative NPRS scores in two groups had no significant difference (P [ 0.05) (Table 4). Radiographic Evaluation Average height of fused vertebral bodies before and after surgery in two groups is shown in Table 5. The postoperative heights of fused vertebral bodies in two groups were significantly different from pre-operative values (P \ 0.05), the difference was statistically significant. However, the average height of fused vertebral bodies had no significant difference between two groups (P [ 0.05). Post-operative Cobb angles of fused vertebral bodies were different from pre-operative Cobb angles in two groups (P \ 0.05), which were statistically significant. The angular loss in anterior surgical approach group was (1.44 ± 0.44)° after 1 year and in posterior surgical approach group was (3.80 ± 0.36)° after 1 year, the angular loss in posterior surgical approach group was bigger than anterior surgical approach group (P \ 0.05), which was statistically different (Table 6).
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Multi-segmental cervical degeneration diseases mainly include posterior longitudinal ligament ossification and cervical spondylotic myelopathy, which often cause spasm, progressive paralysis, or even dysneuria [11, 12]. Multisegmental cervical degeneration disease often involves 2–4 vertebras between C3–C7, and can cause cervical instability, hyperostosis of ligaments and cervical vertebra, compression of the nerve root and spinal cord. Thus, nerve decompression is the key of treatment [13–15]. Any effective method should properly decompress, recover the physiological curvature of cervical vertebra and reestablish the stability of cervical vertebra. At present, the surgical treatments for multi-segmental degeneration disease include anterior approach surgery, posterior approach surgery and combined approach surgery. The anterior approach surgery can directly relieve the compression, effectively decompress to improve the functional recovery of cervical vertebra [16]. Besides, anterior approach surgery can be done at awake state under open view to prevent secondary injure. Posterior surgery is usually suitable for some diseases which are not fit for anterior approach surgery such as thickening of ligamentum flavum, developmental spinal canal stenosis, OPLL and multi-segmental cervical spondylotic myelopathy complicated with OPLL [17, 18]. In recent years, as the development of cervical vertebral surgery, many new surgical techniques have been applied
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Table 6 Comparison of Cobb angle of fused vertebral bodies before and after surgery in two groups (°, x ± s) Group
Cases (n)
Pre-operative
Post-operative 1 week
Post-operative 6 months
Post-operative 1 year
Angle loss post-operative 1 year
Anterior approach
184
1.93 ± 0.12
8.69 ± 0.82
8.14 ± 0.51
7.25 ± 0.38
1.44 ± 0.44*
Posterior approach
184
1.86 ± 0.14
8.83 ± 0.25
7.94 ± 0.52
5.03 ± 0.61
3.80 ± 0.36
*
Represent P \ 0.05 compared with posterior surgical approach group
Table 7 Comparison of cytokine expressions in two groups
Group
Cases (n)
IL-1 (ng/L)
IL-6 (pg/mL)
TNF-a (ng/mL)
MMP-3 (lg/L)
Anterior approach
184
5.49 ± 1.38
29.35 ± 8.24
0.48 ± 0.19
0.43 ± 0.09
Posterior approach
184
5.18 ± 1.24
32.11 ± 8.06
0.51 ± 0.17
0.37 ± 0.11
and new biomaterials have appeared. Despite various options available, the decision to use either an anterior or a posterior approach and the choice of specific procedure is constantly under the debate in clinical settings. In this study, we compared the clinical outcomes of the two methods in treating multi-segmental cervical degeneration hoping to provide some evidence for clinical decisionmaking. Our study showed that perioperative parameters including operative time, intraoperative blood loss and length of stay showed no difference between the two groups. JOA score, NDI scores and NPRS scores all showed a significant improvement after the surgery in both groups; however, when comparing the two methods, only NDI scores showed a better improvement in anterior group compared with posterior group at different follow-up time points, while the rest of the scores did not show any difference between the two groups. Radiographic outcomes showed that the average height of fused vertebral bodies after surgery in two groups was significantly different from pre-operative height, and angle loss in posterior surgical approach group was significantly higher than anterior surgical approach. Cytokines including IL-1, IL-6, TNF-a and MMP-3 in two groups had no statistical difference. Our study suggested that both anterior and posterior method provide effective treatment for multi-segmental cervical degeneration. Compared with posterior approach, anterior method achieved a better clinical outcome during the 1-year follow-up. Other researchers have done the similar comparative studies on the two methods [19–26], and the results are controversial. A recent meta-analysis reported that for multi-segmental cervical disease patients, the final followup JOA score for the anterior group was significantly higher than the posterior group in the ‘follow-up time B5 years’ subgroup, but had no significant differences in the ‘follow-up time [5 years’ subgroup [27]. The recovery rate for the anterior group was also significantly higher
than the posterior group in the ‘follow-up time B5 years’ subgroup. Although JOA scores and recovery rate in our study did not show any difference between the two groups within 1-year follow-up, the overall data, especially NDI scores and radiographic results from our study are in consistent with the meta-analysis. Recent research about the biochemical mechanism of cervical degeneration and the effect on neurological function showed that cytokines play important role in the pathology of cervical degeneration [28, 29]. IL-1, IL-6, TNF-a and MMP-3 are proven to be closely related to cervical degeneration diseases [30–33]. In this study, no difference of cytokine level was found between the two groups suggesting the similar degree of cervical degeneration. In conclusion, anterior approach surgery and posteriors approach surgery are both effective methods to treat multisegmental cervical degeneration, and anterior approach had better clinical outcomes within 1-year follow-up. References 1. Jawahar, A., Cavanaugh, D. A., Kerr, E. J, I. I. I., et al. (2010). Total disc arthroplasty does not affect the incidence of adjacent segment degeneration in cervical spine: results of 93 patients in three prospective randomized clinical trials. The Spine Journal, 10(12), 1043–1048. 2. Yang, B., Li, H., Zhang, T., et al. (2012). The incidence of adjacent segment degeneration after cervical disc arthroplasty (CDA): A meta analysis of randomized controlled trials. PLoS One, 7(4), e35032. 3. Hussain, M., Natarajan, R. N., An, H. S., et al. (2012). Progressive disc degeneration at C5–C6 segment affects the mechanics between disc heights and posterior facets above and below the degenerated segment: A flexion–extension investigation using a poroelastic C3–T1 finite element model. Medical Engineering & Physics, 34(5), 552–558. 4. Nunley, P. D., Jawahar, A., Kerr, E. J., et al. (2012). Factors affecting the incidence of symptomatic adjacent-level disease in cervical spine after total disc arthroplasty: 2- to 4-year follow-up of 3 prospective randomized trials. Spine, 37(6), 445–451.
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