臺灣博碩士論文加值系統

脊椎後方融合術是目前廣泛應用於治療脊椎變形、退化及不穩定等脊椎相關疾病的手術方式。由於生物力學的發展、先進醫療器材的開發及民眾對於生活品質的要求，脊椎後方融合術實施數量及整體醫療花費與年俱增。雖能有效治療病患症狀，但其相關術後併發症常需再次手術以維持治療效果，將降低臨床成效並提高醫療花費。本研究使用人體屍骨及豬隻試樣進行體外生物力學研究，目的為探討脊椎後方融合術的併發症，針對常見的短期的植入物鬆脫及長期的鄰近節椎間盤提早退化的問題進行探討，並提出未來植入物的設計方向。
本研究第一部分，探討椎弓根螺釘與周圍骨組織間隙的拉出強度關係，研究使用疲勞負載來模擬日常生活中脊椎的受力情形，並藉由影像分析椎弓根的幾何結構與拉出強度間的關係。研究結果顯示，當椎弓根螺釘與周圍骨組織間隙達1mm時其拉出強度已顯著下降，此研究成果將有助於臨床醫師判斷植入物鬆脫的狀態。研究也發現植入6mm的椎弓根螺釘於人體骨質疏鬆的胸椎時，若植入的椎弓根緻密骨於椎弓根內的比例大於0.73時，能降低植入物鬆脫的機率，讓醫師能在術前規劃適合螺釘植入的椎弓根區域。
本研究第二部分，探討彈性連接桿與剛性連接桿植入系統對於脊椎椎間盤高度及椎間核壓力的影響，以及兩種植入物的受力及對周圍骨組織的受力影響。研究結果顯示，使用彈性連接桿植入系統相較於傳統的剛性連接桿能使脊椎的生物力學特性更接近健康時的狀態。另外使用彈性連接桿能降低植入物本身及螺釘附近的骨組織應力，證明使用彈性連接桿有可能降低鄰近節提早退化及降低植入物損壞的風險，以提供臨床醫師使用不同器械時的參考方向。
本研究第三部分，探討植入節的活動度變化對於其鄰近節的生物力學代償情形。研究結果指出，隨著植入節的活動度增加，則鄰近節的活動角度及椎間核壓力代償現象則有下降的趨勢，且於前彎動作下植入節的最大活動角度為4.04°時，以及在後仰動作下活動角度為2.41°時，可以提供植入節達到穩定的情形，同時並不會造成鄰近節過度的代償情形，因此可以避免鄰近節提早退化的發生，以提供未來新型固定器設計的參考方向。
本論文對脊椎後方融合術的併發症進行一系列的生物力學研究，並提出可能的解決方向。研究成果期能提供醫事人員施行脊椎後方融合術時的參考，以降低併發症發生及再次手術的機率，使患者有更好的復原情形及生活品質，增進此手術的長期效益。

Posterior Lumbar Interbody Fusion (PLIF) is one of the most common surgical techniques employed to treat spinal deformity, degeneration and other instability related conditions. With the improved understanding of the spine biomechanics combined with the advancement of medical devices as well as the heightened expectations of the general public in pursuing better health and quality of life, the demand for PLIF is ever increasing in the modern society. Despite its well-published effectiveness in relieving clinical symptoms, the frequent development of secondary complications requiring revision surgery associated with PLIF inevitably reduces its clinical efficacy. It is therefore the primary aim of the current project to investigate the mechanisms underlying the development of secondary complications associated with PLIF through a series of in-vitro studies using both porcine and human cadaver specimens. The secondary aim of the project focused on the issues of implant failure and the development of adjacent segment disease after instrumentation and more importantly, discussed some plausible design modifications for future implant development.
The first study of the project was an in-vitro cadaveric study designed to determine the exact role of the pedicular cortical bone composition and the screw-bone gap on the screw fixation failure. The results of the study identified a significant correlation between cortical bone area ratio and the screw pullout strength. Presented results also demonstrated that the fatigue loading induced screw-bone gap of 1 mm was sufficient to cause a significant decrease in the pullout strength. However, a cortical bone area ratio of 0.73 or higher in this group was able to preserve most of the screw-bone interfacial strength and subsequently may play an important role in preventing a complete implant failure in clinical practice.
The second study in the series was an in-vitro fatigue-loading test utilizing porcine specimens to comparatively analyze the biomechanical performance of PEEK and Titanium rods construct subjected to a battery of fatigue loading testing. Based on the results, it was determined that the differences in biomechanical characteristics of PEEK and Titanium rods construct when subjected to fatigue loading. More specifically, the result is indicative of the potential benefits of the PEEK rods construct in reducing the risks of adjacent segment disease and implant failure rates.
The final study in this series investigated the effect of altered mobility of the instrumented level and its consequential impact on the biomechanical characteristics of the adjacent segment levels. The outcome of the study demonstrated that the increasing range of motion at the instrumented level is associated with decreased compensatory motion and intra-discal pressure at the adjacent segments. It was also determined that a maximum of 4.04° into flexion and 2.41° into extension achieved maximum stability of the instrumented level coupled with minimal biomechanical compensatory at the adjacent levels. Such finding is of significant clinical value as it provides a guideline for the future design and development of more advanced spinal implants.
Overall, the series of studies comprised in the current project investigated the possible mechanisms associated with the development of secondary complications post PLIF surgery and proposed plausible solutions to overcome each of the shortcomings by identifying more appropriate medical material or through modification of device design. The outcomes of the project provided valuable knowledge base and guidelines for clinicians performing PLIF and it is hoped that the presented information will ultimately assist in the reduction of secondary complications and revision surgery associated with PLIF and subsequently improve the long-term quality of life for the patients.

口試委員審定書 i
誌謝 ii
中文摘要 iii
Abstract v
目錄 viii
圖目錄 xii
表目錄 xv
第一章 緒論 1
1.1 脊椎基本架構 1
1.2 脊椎後方融合術適用症狀 2
1.3 腰椎後方融合術常見併發症 4
1.3.1 椎弓根螺釘鬆脫 4
1.3.2 鄰近節椎間盤提早退化 6
1.4 對於鄰近節提早退化問題的前瞻性治療 7
1.5 植入節活動度對於鄰近節的生物力學影響 8
1.6 研究目的 10
1.7 論文架構 10
第二章 椎弓根螺釘鬆脫 11
2.1 前言 11
2.2 材料與方法 14
2.2.1 試樣準備 14
2.2.2 緻密骨於椎弓根內的比例量測 16
2.2.3 椎弓根螺釘植入 17
2.2.4 疲勞負載 18
2.2.5 椎弓根螺釘拉出強度測試 19
2.2.6 統計分析 21
2.3 實驗結果 21
2.3.1 試樣分組初始特性 21
2.3.2 X光影像 21
2.3.3 椎弓根螺釘拉出強度 22
2.3.4 骨質密度與拉出強度相關性分析 23
2.3.5 緻密骨於椎弓根內的比例與拉出強度相關性分析 23
2.3.6 安全的緻密骨於椎弓根內的比例範圍 24
2.4 討論 24
2.5 結論 28
第三章 剛性及彈性植入物系統對於脊椎生物力學的影響 29
3.1 前言 29
3.2 材料與方法 32
3.2.1 試樣準備 32
3.2.2 椎間盤高度變化 34
3.2.3 椎間核壓力變化 34
3.2.4 植入物與椎弓根螺釘附近骨組織的應力 36
3.2.5 疲勞負載 37
3.2.6 染色切片 38
3.2.7 統計分析 39
3.3 實驗結果 39
3.3.1 椎間盤高度變化 40
3.3.2 椎間核壓力變化 43
3.3.3 連接桿與椎弓根螺釘附近骨組織的應力 46
3.3.4 染色切片 46
3.4 討論 47
3.5 結論 50
第四章 植入節活動度對於鄰近節的生物力學影響 51
4.1 前言 51
4.2 材料與方法 53
4.2.1 試樣準備 54
4.2.2 活動度測試 57
4.2.3 椎間核壓力變化 58
4.2.4 椎間孔面積變化 59
4.2.5 實驗流程 60
4.2.6 統計分析 62
4.3 實驗結果 62
4.3.1 活動度測試 63
4.3.2 椎間核壓力變化 67
4.3.3 椎間孔面積變化 71
4.4 討論 75
4.5 結論 78
第五章 結論與未來展望 79
5.1 結論 79
5.2 未來展望 80
參考文獻 81

1.Roughley PJ. Biology of intervertebral disc aging and degeneration: involvement of the extracellular matrix. Spine 2004;29:2691-9.
2.Roberts S. Disc morphology in health and disease. Biochem Soc Trans 2002;30:864-9.
3.Allen M, VetMB P, Schoonmaker J, et al. Preclinical evaluation of a poly (vinyl alcohol) hydrogel implant as a replacement for the nucleus pulposus. Spine 2004;29:515.
4.Meakin JR, Hukins DW. Effect of removing the nucleus pulposus on the deformation of the annulus fibrosus during compression of the intervertebral disc. J Biomech 2000;33:575-80.
5.Wilke HJ, Neef P, Caimi M, et al. New in vivo measurements of pressures in the intervertebral disc in daily life. Spine (Phila Pa 1976) 1999;24:755-62.
6.Panjabi MM. Clinical spinal instability and low back pain. Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology 2003;13:371-9.
7.Panjabi MM. The stabilizing system of the spine. Part I. Function, dysfunction, adaptation, and enhancement. Journal of spinal disorders 1992;5:383-9; discussion 97.
8.Palepu V, Kodigudla M, Goel VK. Biomechanics of disc degeneration. Advances in orthopedics 2012;2012:726210.
9.Boucher HH. A method of spinal fusion. Journal of Bone & Joint Surgery, British Volume 1959;41:248-59.
10.Abumi K, Kaneda K. Pedicle screw fixation for nontraumatic lesions of the cervical spine. Spine 1997;22:1853.
11.Hadjipavlou AG, Nicodemus CL, Al-Hamdan FA, et al. Correlation of bone equivalent mineral density to pull-out resistance of triangulated pedicle screw construct. Journal of spinal disorders 1997;10:12-9.
12.Roy-Camille R, Saillant G, Mazel C. Internal fixation of the lumbar spine with pedicle screw plating. Clinical Orthopaedics & Related Research 1986;203:7.
13.Roy-Camille R, Saillant G, Mazel C. Plating of thoracic, thoracolumbar, and lumbar injuries with pedicle screw plates. The Orthopedic clinics of North America 1986;17:147.
14.Yoshihara H. Rods in spinal surgery: a review of the literature. The spine journal : official journal of the North American Spine Society 2013;13:1350-8.
15.Schizas C, Kulik G, Kosmopoulos V. Disc degeneration: current surgical options. European cells & materials 2010;20:306-15.
16.Wang JC, Mummaneni PV, Haid RW. Current treatment strategies for the painful lumbar motion segment: posterolateral fusion versus interbody fusion. Spine (Phila Pa 1976) 2005;30:S33-43.
17.Rajaee SS, Bae HW, Kanim LE, et al. Spinal fusion in the United States: analysis of trends from 1998 to 2008. Spine (Phila Pa 1976) 2012;37:67-76.
18.Deyo RA, Gray DT, Kreuter W, et al. United States trends in lumbar fusion surgery for degenerative conditions. Spine (Phila Pa 1976) 2005;30:1441-5; discussion 6-7.
19.Yoshihara H, Yoneoka D. National trends in the surgical treatment for lumbar degenerative disc disease: US, 2000-2009. The spine journal : official journal of the North American Spine Society 2014.
20.Verla T, Adogwa O, Fatemi P, et al. Clinical implication of complications on patient perceived health status following spinal fusion surgery. Journal of Clinical Neuroscience 2014.
21.Goz V, Weinreb JH, McCarthy I, et al. Perioperative complications and mortality after spinal fusions: analysis of trends and risk factors. Spine (Phila Pa 1976) 2013;38:1970-6.
22.Proietti L, Scaramuzzo L, Schiro GR, et al. Complications in lumbar spine surgery: A retrospective analysis. Indian journal of orthopaedics 2013;47:340-5.
23.Lad SP, Babu R, Baker AA, et al. Complications, reoperation rates, and health-care cost following surgical treatment of lumbar spondylolisthesis. The Journal of bone and joint surgery. American volume 2013;95:e162.
24.Davne SH, Myers DL. Complications of lumbar spinal fusion with transpedicular instrumentation. Spine 1992;17:S184.
25.McAfee P, Weiland DJ, Carlow JJ. Survivorship analysis of pedicle spinal instrumentation. Spine 1991;16:S428.
26.Okuyama K, Abe E, Suzuki T, et al. Influence of bone mineral density on pedicle screw fixation a study of pedicle screw fixation augmenting posterior lumbar interbody fusion in elderly patients. The Spine Journal 2001;1:402-7.
27.Zindrick M, Wiltse L, Widell E, et al. A biomechanical study of intrapeduncular screw fixation in the lumbosacral spine. Clinical Orthopaedics & Related Research 1986;203:99.
28.Ghiselli G, Wang JC, Bhatia NN, et al. Adjacent segment degeneration in the lumbar spine. The Journal of bone and joint surgery. American volume 2004;86-a:1497-503.
29.Hilibrand AS, Robbins M. Adjacent segment degeneration and adjacent segment disease: the consequences of spinal fusion? The spine journal : official journal of the North American Spine Society 2004;4:190s-4s.
30.Chow DH, Luk KD, Evans JH, et al. Effects of short anterior lumbar interbody fusion on biomechanics of neighboring unfused segments. Spine (Phila Pa 1976) 1996;21:549-55.
31.Ha KY, Schendel MJ, Lewis JL, et al. Effect of immobilization and configuration on lumbar adjacent-segment biomechanics. Journal of spinal disorders 1993;6:99-105.
32.Esses SI, Doherty BJ, Crawford MJ, et al. Kinematic evaluation of lumbar fusion techniques. Spine (Phila Pa 1976) 1996;21:676-84.
33.Cunningham BW, Kotani Y, McNulty PS, et al. The effect of spinal destabilization and instrumentation on lumbar intradiscal pressure: an in vitro biomechanical analysis. Spine (Phila Pa 1976) 1997;22:2655-63.
34.Cunningham BW, Sefter JC, Shono Y, et al. Static and cyclical biomechanical analysis of pedicle screw spinal constructs. Spine (Phila Pa 1976) 1993;18:1677-88.
35.Kim K, Park WM, Kim YH, et al. Stress analysis in a pedicle screw fixation system with flexible rods in the lumbar spine. Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine 2010;224:477-85.
36.Cripton PA, Jain GM, Wittenberg RH, et al. Load-sharing characteristics of stabilized lumbar spine segments. Spine (Phila Pa 1976) 2000;25:170-9.
37.Sengupta DK. Dynamic stabilization devices in the treatment of low back pain. Orthop Clin North Am 2004;35:43-56.
38.Kaner T, Sasani M, Oktenoglu T, et al. Dynamic stabilization of the spine: a new classification system. Turkish neurosurgery 2010;20:205-15.
39.Gomleksiz C, Sasani M, Oktenoglu T, et al. A short history of posterior dynamic stabilization. Advances in orthopedics 2012;2012:629698.
40.Obernauer J, Kavakebi P, Quirbach S, et al. Pedicle-based non-fusion stabilization devices: a critical review and appraisal of current evidence. Advances and technical standards in neurosurgery 2014;41:131-42.
41.Athanasakopoulos M, Mavrogenis AF, Triantafyllopoulos G, et al. Posterior spinal fusion using pedicle screws. Orthopedics 2013;36:e951-7.
42.Ormond DR, Albert L, Jr., Das K. Polyetheretherketone (PEEK) rods in lumbar spine degenerative disease: a case series. Journal of spinal disorders & techniques 2012:In press.
43.Abode-Iyamah K, Kim SB, Grosland N, et al. Spinal motion and intradiscal pressure measurements before and after lumbar spine instrumentation with titanium or PEEK rods. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia 2013:In press.
44.Videman T, Sarna S, Battie MC, et al. The long-term effects of physical loading and exercise lifestyles on back-related symptoms, disability, and spinal pathology among men. Spine (Phila Pa 1976) 1995;20:699-709.
45.Wang JL, Wu TK, Lin TC, et al. Rest cannot always recover the dynamic properties of fatigue-loaded intervertebral disc. Spine (Phila Pa 1976) 2008;33:1863-9.
46.Schaeren S, Broger I, Jeanneret B. Minimum four-year follow-up of spinal stenosis with degenerative spondylolisthesis treated with decompression and dynamic stabilization. Spine (Phila Pa 1976) 2008;33:E636-42.
47.Schnake KJ, Schaeren S, Jeanneret B. Dynamic stabilization in addition to decompression for lumbar spinal stenosis with degenerative spondylolisthesis. Spine (Phila Pa 1976) 2006;31:442-9.
48.Schmoelz W, Huber JF, Nydegger T, et al. Dynamic stabilization of the lumbar spine and its effects on adjacent segments: an in vitro experiment. Journal of spinal disorders & techniques 2003;16:418-23.
49.Johnell O, Kanis JA. An estimate of the worldwide prevalence and disability associated with osteoporotic fractures. Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA 2006;17:1726-33.
50.Esses SI, Sachs BL, Dreyzin V. Complications associated with the technique of pedicle screw fixation. A selected survey of ABS members. Spine (Phila Pa 1976) 1993;18:2231-8; discussion 8-9.
51.Okuyama K, Abe E, Suzuki T, et al. Influence of bone mineral density on pedicle screw fixation: a study of pedicle screw fixation augmenting posterior lumbar interbody fusion in elderly patients. The spine journal : official journal of the North American Spine Society 2001;1:402-7.
52.Higashino K, Kim JH, Horton WC, et al. A biomechanical study of two different pedicle screw methods for fixation in osteoporotic and nonosteoporotic vertebrae. Journal of surgical orthopaedic advances 2012;21:198-203.
53.Shea TM, Laun J, Gonzalez-Blohm SA, et al. Designs and techniques that improve the pullout strength of pedicle screws in osteoporotic vertebrae: current status. BioMed research international 2014;2014:748393.
54.Krenn MH, Piotrowski WP, Penzkofer R, et al. Influence of thread design on pedicle screw fixation. Laboratory investigation. Journal of neurosurgery. Spine 2008;9:90-5.
55.Patel PS, Shepherd DE, Hukins DW. The effect of screw insertion angle and thread type on the pullout strength of bone screws in normal and osteoporotic cancellous bone models. Medical engineering & physics 2010;32:822-8.
56.Coe JD, Warden KE, Herzig MA, et al. Influence of bone mineral density on the fixation of thoracolumbar implants. A comparative study of transpedicular screws, laminar hooks, and spinous process wires. Spine 1990;15:902.
57.Krag MH. Biomechanics of thoracolumbar spinal fixation: A review. Spine 1991;16:S84.
58.Krag M, Beynnon B, Pope MH, et al. An internal fixator for posterior application to short segments of the thoracic, lumbar, or lumbosacral spine design and testing. Clinical Orthopaedics & Related Research 1986;203:75.
59.Yamagata M, Kitahara H, Minami S, et al. Mechanical stability of the pedicle screw fixation systems for the lumbar spine. Spine 1992;17:51.
60.Burval DJ, McLain RF, Milks R, et al. Primary pedicle screw augmentation in osteoporotic lumbar vertebrae: biomechanical analysis of pedicle fixation strength. Spine (Phila Pa 1976) 2007;32:1077-83.
61.Hirano T, Hasegawa K, Takahashi HE, et al. Structural characteristics of the pedicle and its role in screw stability. Spine (Phila Pa 1976) 1997;22:2504-9; discussion 10.
62.Weinstein JN, Rydevik BL, Rauschning W. Anatomic and technical considerations of pedicle screw fixation. Clinical orthopaedics and related research 1992:34-46.
63.Ricci WM, Tornetta P, 3rd, Petteys T, et al. A comparison of screw insertion torque and pullout strength. Journal of orthopaedic trauma 2010;24:374-8.
64.Shah AH, Behrents RG, Kim KB, et al. Effects of screw and host factors on insertion torque and pullout strength. The Angle orthodontist 2012;82:603-10.
65.Helgeson MD, Kang DG, Lehman RA, Jr., et al. Tapping insertional torque allows prediction for better pedicle screw fixation and optimal screw size selection. The spine journal : official journal of the North American Spine Society 2013;13:957-65.
66.Wilke HJ, Jungkunz B, Wenger K, et al. Spinal segment range of motion as a function of in vitro test conditions: effects of exposure period, accumulated cycles, angular-deformation rate, and moisture condition. The Anatomical record 1998;251:15-9.
67.Lill CA, Schneider E, Goldhahn J, et al. Mechanical performance of cylindrical and dual core pedicle screws in calf and human vertebrae. Archives of orthopaedic and trauma surgery 2006;126:686-94.
68.Krag MH, Weaver DL, Beynnon BD, et al. Morphometry of the thoracic and lumbar spine related to transpedicular screw placement for surgical spinal fixation. Spine (Phila Pa 1976) 1988;13:27-32.
69.Misenhimer GR, Peek RD, Wiltse LL, et al. Anatomic analysis of pedicle cortical and cancellous diameter as related to screw size. Spine (Phila Pa 1976) 1989;14:367-72.
70.Kothe R, O''Holleran JD, Liu W, et al. Internal architecture of the thoracic pedicle. An anatomic study. Spine (Phila Pa 1976) 1996;21:264-70.
71.Panjabi MM, Takata K, Goel V, et al. Thoracic human vertebrae. Quantitative three-dimensional anatomy. Spine (Phila Pa 1976) 1991;16:888-901.
72.Koller H, Fierlbeck J, Auffarth A, et al. Impact of constrained dual-screw anchorage on holding strength and the resistance to cyclic loading in anterior spinal deformity surgery: a comparative biomechanical study. Spine (Phila Pa 1976) 2014;39:E390-8.
73.Hsu CC, Chao CK, Wang JL, et al. Increase of pullout strength of spinal pedicle screws with conical core: biomechanical tests and finite element analyses. Journal of orthopaedic research : official publication of the Orthopaedic Research Society 2005;23:788-94.
74.Tsai KJ, Murakami H, Horton WC, et al. Pedicle screw fixation strength: a biomechanical comparison between 4.5-mm and 5.5-mm diameter screws in osteoporotic upper thoracic vertebrae. Journal of surgical orthopaedic advances 2009;18:23-7.
75.Kim YY, Choi WS, Rhyu KW. Assessment of pedicle screw pullout strength based on various screw designs and bone densities-an ex vivo biomechanical study. The spine journal : official journal of the North American Spine Society 2012;12:164-8.
76.Pare PE, Chappuis JL, Rampersaud R, et al. Biomechanical evaluation of a novel fenestrated pedicle screw augmented with bone cement in osteoporotic spines. Spine (Phila Pa 1976) 2011;36:E1210-4.
77.Wu Z, Nassar SA, Yang X. Pullout performance of self-tapping medical screws. Journal of biomechanical engineering 2011;133:111002.
78.Saraf SK, Singh RP, Singh V, et al. Pullout strength of misplaced pedicle screws in the thoracic and lumbar vertebrae - A cadaveric study. Indian journal of orthopaedics 2013;47:238-43.
79.Koller H, Zenner J, Hitzl W, et al. The impact of a distal expansion mechanism added to a standard pedicle screw on pullout resistance. A biomechanical study. The spine journal : official journal of the North American Spine Society 2013;13:532-41.
80.Brasiliense LB, Lazaro BC, Reyes PM, et al. Characteristics of immediate and fatigue strength of a dual-threaded pedicle screw in cadaveric spines. The spine journal : official journal of the North American Spine Society 2013;13:947-56.
81.Yuksel KZ, Adams MS, Chamberlain RH, et al. Pullout resistance of thoracic extrapedicular screws used as a salvage procedure. The spine journal : official journal of the North American Spine Society 2007;7:286-91.
82.Park P, Garton HJ, Gala VC, et al. Adjacent segment disease after lumbar or lumbosacral fusion: review of the literature. Spine 2004;29:1938-44.
83.Aota Y, Kumano K, Hirabayashi S. Postfusion instability at the adjacent segments after rigid pedicle screw fixation for degenerative lumbar spinal disorders. Journal of spinal disorders 1995;8:464-73.
84.Panjabi M, Malcolmson G, Teng E, et al. Hybrid testing of lumbar CHARITE discs versus fusions. Spine 2007;32:959-66; discussion 67.
85.Nohara H, Kanaya F. Biomechanical study of adjacent intervertebral motion after lumbar spinal fusion and flexible stabilization using polyethylene-terephthalate bands. Journal of spinal disorders & techniques 2004;17:215-9.
86.Schmoelz W, Huber JF, Nydegger T, et al. Influence of a dynamic stabilisation system on load bearing of a bridged disc: an in vitro study of intradiscal pressure. European Spine Journal 2006;15:1276-85.
87.Nachemson A. The load on lumbar disks in different positions of the body. Clinical Orthopaedics & Related Research 1966;45:107-22.
88.Abe E, Nickel T, Buttermann GR, et al. Lumbar intradiscal pressure after posterolateral fusion and pedicle screw fixation. Tohoku Journal of Experimental Medicine 1998;186:243-53.
89.Cunningham BW, Kotani Y, McNulty PS, et al. The effect of spinal destabilization and instrumentation on lumbar intradiscal pressure: an in vitro biomechanical analysis. Spine 1997;22:2655-63.
90.Molz FJ, Partin JI, Kirkpatrick JS. The acute effects of posterior fusion instrumentation on kinematics and intradiscal pressure of the human lumbar spine. Journal of spinal disorders & techniques 2003;16:171-9.
91.Weinhoffer SL, Guyer RD, Herbert M, et al. Intradiscal pressure measurements above an instrumented fusion. A cadaveric study. Spine 1995;20:526-31.
92.Kuo YW, Wang JL. Rheology of intervertebral disc: an ex vivo study on the effect of loading history, loading magnitude, fatigue loading, and disc degeneration. Spine (Phila Pa 1976) 2010;35:E743-52.
93.Pfirrmann CW, Metzdorf A, Zanetti M, et al. Magnetic resonance classification of lumbar intervertebral disc degeneration. Spine (Phila Pa 1976) 2001;26:1873-8.
94.Zdeblick TA. A prospective, randomized study of lumbar fusion. Preliminary results. Spine (Phila Pa 1976) 1993;18:983-91.
95.Ishihara H, Osada R, Kanamori M, et al. Minimum 10-year follow-up study of anterior lumbar interbody fusion for isthmic spondylolisthesis. Journal of spinal disorders 2001;14:91-9.
96.Miyakoshi N, Abe E, Shimada Y, et al. Outcome of one-level posterior lumbar interbody fusion for spondylolisthesis and postoperative intervertebral disc degeneration adjacent to the fusion. Spine (Phila Pa 1976) 2000;25:1837-42.
97.McMillan DW, Garbutt G, Adams MA. Effect of sustained loading on the water content of intervertebral discs: implications for disc metabolism. Annals of the rheumatic diseases 1996;55:880-7.
98.Iatridis JC, MacLean JJ, Roughley PJ, et al. Effects of mechanical loading on intervertebral disc metabolism in vivo. The Journal of bone and joint surgery. American volume 2006;88 Suppl 2:41-6.
99.Stokes IA, Iatridis JC. Mechanical conditions that accelerate intervertebral disc degeneration: overload versus immobilization. Spine (Phila Pa 1976) 2004;29:2724-32.
100.Setton LA, Chen J. Cell mechanics and mechanobiology in the intervertebral disc. Spine (Phila Pa 1976) 2004;29:2710-23.
101.Ahn YH, Chen WM, Lee KY, et al. Comparison of the load-sharing characteristics between pedicle-based dynamic and rigid rod devices. Biomedical materials (Bristol, England) 2008;3:044101.
102.Turner JL, Paller DJ, Murrell CB. The mechanical effect of commercially pure titanium and polyetheretherketone rods on spinal implants at the operative and adjacent levels. Spine (Phila Pa 1976) 2010;35:E1076-82.
103.Niu CC, Chen WJ, Chen LH, et al. Reduction-fixation spinal system in spondylolisthesis. American journal of orthopedics (Belle Mead, N.J.) 1996;25:418-24.
104.Katonis P, Christoforakis J, Kontakis G, et al. Complications and problems related to pedicle screw fixation of the spine. Clinical orthopaedics and related research 2003:86-94.
105.Kurtz SM, Lanman TH, Higgs G, et al. Retrieval analysis of PEEK rods for posterior fusion and motion preservation. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society 2013;22:2752-9.
106.Alini M, Eisenstein SM, Ito K, et al. Are animal models useful for studying human disc disorders/degeneration? European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society 2008;17:2-19.
107.Lee CK. Accelerated degeneration of the segment adjacent to a lumbar fusion. Spine 1988;13:375-7.
108.Park P, Garton HJ, Gala VC, et al. Adjacent segment disease after lumbar or lumbosacral fusion: review of the literature. Spine (Phila Pa 1976) 2004;29:1938-44.
109.Chou WY, Hsu CJ, Chang WN, et al. Adjacent segment degeneration after lumbar spinal posterolateral fusion with instrumentation in elderly patients. Archives of orthopaedic and trauma surgery 2002;122:39-43.
110.Etebar S, Cahill DW. Risk factors for adjacent-segment failure following lumbar fixation with rigid instrumentation for degenerative instability. J Neurosurg 1999;90:163-9.
111.Hongo M, Gay RE, Zhao KD, et al. Junction kinematics between proximal mobile and distal fused lumbar segments: biomechanical analysis of pedicle and hook constructs. The spine journal : official journal of the North American Spine Society 2009;9:846-53.
112.Untch C, Liu Q, Hart R. Segmental motion adjacent to an instrumented lumbar fusion: the effect of extension of fusion to the sacrum. Spine (Phila Pa 1976) 2004;29:2376-81.
113.Putzier M, Hoff E, Tohtz S, et al. Dynamic stabilization adjacent to single-level fusion: part II. No clinical benefit for asymptomatic, initially degenerated adjacent segments after 6 years follow-up. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society 2010;19:2181-9.
114.Delank K-S, Gercek E, Kuhn S, et al. How does spinal canal decompression and dorsal stabilization affect segmental mobility? A biomechanical study. Archives of Orthopaedic & Trauma Surgery 2010;130:285-92.
115.Cheng BC, Gordon J, Cheng J, et al. Immediate biomechanical effects of lumbar posterior dynamic stabilization above a circumferential fusion. Spine (Phila Pa 1976) 2007;32:2551-7.
116.Panjabi MM. Hybrid multidirectional test method to evaluate spinal adjacent-level effects. Clinical Biomechanics 2007;22:257-65.
117.Panjabi MM. Hybrid multidirectional test method to evaluate spinal adjacent-level effects. Clinical biomechanics (Bristol, Avon) 2007;22:257-65.
118.Ryan G, Pandit A, Apatsidis D. Stress distribution in the intervertebral disc correlates with strength distribution in subdiscal trabecular bone in the porcine lumbar spine. Clin Biomech (Bristol, Avon) 2008;23:859-69.
119.Schmoelz W, Huber JF, Nydegger T, et al. Influence of a dynamic stabilisation system on load bearing of a bridged disc: an in vitro study of intradiscal pressure. Eur Spine J 2006;15:1276-85.
120.Morishita Y, Hida S, Naito M, et al. Neurogenic intermittent claudication in lumbar spinal canal stenosis: the clinical relationship between the local pressure of the intervertebral foramen and the clinical findings in lumbar spinal canal stenosis. Journal of spinal disorders & techniques 2009;22:130-4.