CT and radiographic analysis of sagittal profile changes following thoracoscopic anterior scoliosis surgery

Scoliosis

Geoffrey N Askin¹  Robert D Labrom¹  Eugene J Verzin¹  Clayton J Adam¹  Maree T Izatt¹ 

[1] Paediatric Spine Research Group, Queensland University of Technology and Mater Health Services Brisbane Ltd, Queensland, Australia

关键词: Lumbar lordosis;    Thoracic kyphosis;    Computed tomography (CT);    Sagittal profile;    Adolescent idiopathic scoliosis;    Anterior spinal fusion;    Thoracoscopic anterior spinal fusion;   

Others  :  791490
DOI  :  10.1186/1748-7161-7-15

 received in 2012-04-20, accepted in 2012-08-10,  发布年份 2012

【 摘 要 】

Background

Previous studies report an increase in thoracic kyphosis after anterior approaches and a flattening of sagittal contours following posterior approaches. Difficulties with measuring sagittal parameters on radiographs are avoided with reformatted sagittal CT reconstructions due to the superior endplate clarity afforded by this imaging modality.

Methods

A prospective study of 30 Lenke 1 adolescent idiopathic scoliosis (AIS) patients receiving selective thoracoscopic anterior spinal fusion (TASF) was performed. Participants had ethically approved low dose CT scans at minimum 24 months after surgery in addition to their standard care following surgery. The change in sagittal contours on supine CT was compared to standing radiographic measurements of the same patients and with previous studies. Inter-observer variability was assessed as well as whether hypokyphotic and normokyphotic patient groups responded differently to the thoracoscopic anterior approach.

Results

Mean T5-12 kyphosis Cobb angle increased by 11.8 degrees and lumbar lordosis increased by 5.9 degrees on standing radiographs two years after surgery. By comparison, CT measurements of kyphosis and lordosis increased by 12.3 degrees and 7.0 degrees respectively. 95% confidence intervals for inter-observer variability of sagittal contour measurements on supine CT ranged between 5-8 degrees. TASF had a slightly greater corrective effect on patients who were hypokyphotic before surgery compared with those who were normokyphotic.

Conclusions

Restoration of sagittal profile is an important goal of scoliosis surgery, but reliable measurement with radiographs suffers from poor endplate clarity. TASF significantly improves thoracic kyphosis and lumbar lordosis while preserving proximal and distal junctional alignment in thoracic AIS patients. Supine CT allows greater endplate clarity for sagittal Cobb measurements and linear relationships were found between supine CT and standing radiographic measurements. In this study, improvements in sagittal kyphosis and lordosis following surgery were in agreement with prior anterior surgery studies, and add to the current evidence suggesting that anterior correction is more capable than posterior approaches of addressing the sagittal component of both the instrumented and adjacent non instrumented segments following surgical correction of progressive Lenke 1 idiopathic scoliosis.

【 授权许可】

   
2012 Izatt et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

Figure 4.

Figure 5.

Figure 6.

【 参考文献 】

• [1]Betz RR, Shufflebarger H: Anterior versus posterior instrumentation for the correction of thoracic idiopathic scoliosis. Spine 2001, 26:1095-1100.
• [2]Lowe TG, Betz R, Lenke L, Clements D, Harms J, Newton P, Haher T, Merola A, Wenger D: Anterior single-rod instrumentation of the thoracic and lumbar spine: saving levels. Spine 2003, 28:S208-S216.
• [3]Lonner BS, Kondrachov D, Siddiqi F, Hayes V, Scharf C: Thoracoscopic spinal fusion compared with posterior spinal fusion for the treatment of thoracic adolescent idiopathic scoliosis. J Bone Joint Surg Am 2006, 88:1022-1034.
• [4]Lonner BS, Auerbach JD, Estreicher M, Milby AH, Kean KE: Video-assisted thoracoscopic spinal fusion compared with posterior spinal fusion with thoracic pedicle screws for thoracic adolescent idiopathic scoliosis. J Bone Joint Surg Am 2009, 91:398-408.
• [5]Sucato DJ, Agrawal S, O’Brien MF, Lowe TG, Richards SB, Lenke L: Restoration of thoracic kyphosis after operative treatment of adolescent idiopathic scoliosis: a multicenter comparison of three surgical approaches. Spine 2008, 33:2630-2636.
• [6]Lenke LG, Betz RR, Bridwell KH, Harms J, Clements DH, Lowe TG: Spontaneous lumbar curve coronal correction after selective anterior or posterior thoracic fusion in adolescent idiopathic scoliosis. Spine 1999, 24:1663-1671.
• [7]Potter BK, Kuklo TR, Lenke LG: Radiographic outcomes of anterior spinal fusion versus posterior spinal fusion with thoracic pedicle screws for treatment of Lenke Type I adolescent idiopathic scoliosis curves. Spine 2005, 30:1859-1866.
• [8]Hay D, Izatt MT, Adam CJ, Labrom RD, Askin GN: Radiographic outcomes over time after endoscopic anterior scoliosis correction: a prospective series of 106 patients. Spine 2009, 34:1176-1184.
• [9]Chang MS, Bridwell KH, Lenke LG, Cho W, Baldus C, Auerbach JD, Crawford CH 3rd, O’Shaughnessy BA: Predicting the outcome of selective thoracic fusion in false double major lumbar “C” cases with five- to twenty four-year follow-up. Spine 2010, 35:2128-2133.
• [10]Somerville EW: Rotational lordosis; the development of the single curve. J Bone Joint Surg Br 1952, 34-B:421-427.
• [11]Lawton JO, Dickson RA: The experimental basis of idiopathic scoliosis. Clin Orthop Relat Res 1986, 210:9-17.
• [12]Matsumoto T, Kitahara H, Minami S, Takahashi K, Yamagata M, Moriya H, Tamaki T: Flexibility in the scoliotic spine: three-dimensional analysis. J Spinal Disord 1997, 10:125-131.
• [13]Perdriolle R, Vidal J: Morphology of scoliosis: three-dimensional evolution. Orthopedics 1987, 10:909-915.
• [14]Rhee JM, Bridwell KH, Won DS, Lenke LG, Chotigavanichaya C, Hanson DS: Sagittal plane analysis of adolescent idiopathic scoliosis: the effect of anterior versus posterior instrumentation. Spine 2002, 27:2350-2356.
• [15]Glassman SD, Bridwell K, Dimar JR, Horton W, Berven S, Schwab F: The impact of positive sagittal balance in adult spinal deformity. Spine 2005, 30:2024-2029.
• [16]Newton PO, Yaszay B, Upasani VV, Pawelek JB, Bastrom TP, Lenke LG, Lowe T, Crawford A, Betz R, Lonner B: Preservation of thoracic kyphosis is critical to maintain lumbar lordosis in the surgical treatment of adolescent idiopathic scoliosis. Spine 2010, 35:1365-1370.
• [17]Betz RR, Harms J, Clements DH 3rd, Lenke LG, Lowe TG, Shufflebarger HL, Jeszenszky D, Beele B: Comparison of anterior and posterior instrumentation for correction of adolescent thoracic idiopathic scoliosis. Spine 1999, 24:225-239.
• [18]Lonner BS, Auerbach JD, Levin R, Matusz D, Scharf CL, Panagopoulos G, Sharan AD: Thoracoscopic anterior instrumented fusion for adolescent idiopathic scoliosis with emphasis on the sagittal plane. Spine J 2009, 9:523-529.
• [19]Tis JE, O’Brien MF, Newton PO, Lenke LG, Clements DH, Harms J, Betz RR: Adolescent idiopathic scoliosis treated with open instrumented anterior spinal fusion: five-year follow-up. Spine 2009, 35:64-70.
• [20]Vora V, Crawford A, Babekhir N, Boachie-Adjei O, Lenke L, Peskin M, Charles G, Kim Y: A pedicle screw construct gives an enhanced posterior correction of adolescent idiopathic scoliosis when compared with other constructs: myth or reality. Spine 2007, 32:1869-1874.
• [21]Lehman RA Jr, Lenke LG, Keeler KA, Kim YJ, Buchowski JM, Cheh G, Kuhns CA, Bridwell KH: Operative treatment of adolescent idiopathic scoliosis with posterior pedicle screw-only constructs: minimum three-year follow-up of one hundred fourteen cases. Spine 2008, 33:1598-1604.
• [22]Quan GM, Gibson MJ: Correction of main thoracic adolescent idiopathic scoliosis using pedicle screw instrumentation: does higher implant density improve correction? Spine 2010, 35:562-567.
• [23]Glattes RC, Bridwell KH, Lenke LG, Kim YJ, Rinella A, Edwards C 2nd: Proximal junctional kyphosis in adult spinal deformity following long instrumented posterior spinal fusion: incidence, outcomes, and risk factor analysis. Spine 2005, 30:1643-1649.
• [24]Hollenbeck SM, Glattes RC, Asher MA, Lai SM, Burton DC: The prevalence of increased proximal junctional flexion following posterior instrumentation and arthrodesis for adolescent idiopathic scoliosis. Spine 2008, 33:1675-1681.
• [25]Kim YJ, Bridwell KH, Lenke LG, Kim J, Cho SK: Proximal junctional kyphosis in adolescent idiopathic scoliosis following segmental posterior spinal instrumentation and fusion: minimum 5-year follow-up. Spine 2005, 30:2045-2050.
• [26]Lee GA, Betz RR, Clements DH 3rd, Huss GK: Proximal kyphosis after posterior spinal fusion in patients with idiopathic scoliosis. Spine 1999, 24:795-799.
• [27]Picetti GD 3rd, Pang D, Bueff HU: Thoracoscopic techniques for the treatment of scoliosis: early results in procedure development. Neurosurgery 2002, 51:978-984.
• [28]Lenke LG: Anterior endoscopic discectomy and fusion for adolescent idiopathic scoliosis. Spine 2003, 28:S36-S43.
• [29]Newton PO, Parent S, Marks M, Pawelek J: Prospective evaluation of 50 consecutive scoliosis patients surgically treated with thoracoscopic anterior instrumentation. Spine 2005, 30:S100-S109.
• [30]Grewal H, Betz RR, D’Andrea LP, Clements DH, Porter ST: A prospective comparison of thoracoscopic vs open anterior instrumentation and spinal fusion for idiopathic thoracic scoliosis in children. J Pediatr Surg 2005, 40:153-156.
• [31]Hsieh PC, Koski TR, Sciubba DM, Moller DJ, O’Shaughnessy BA, Li KW, Gokaslan ZL, Ondra SL, Fessler RG, Liu JC: Maximizing the potential of minimally invasive spine surgery in complex spinal disorders. Neurosurg Focus 2008, 25:E19.
• [32]Faro FD, Marks MC, Newton PO, Blanke K, Lenke LG: Perioperative changes in pulmonary function after anterior scoliosis instrumentation: thoracoscopic versus open approaches. Spine 2005, 30:1058-1063.
• [33]Izatt MT, Harvey JR, Adam CJ, Fender D, Labrom RD, Askin GN: Recovery of pulmonary function following endoscopic anterior scoliosis correction: evaluation at 3, 6, 12, and 24 months after surgery. Spine 2006, 31:2469-2477.
• [34]Wong HK, Hee HT, Yu Z, Wong D: Results of thoracoscopic instrumented fusion versus conventional posterior instrumented fusion in adolescent idiopathic scoliosis undergoing selective thoracic fusion. Spine 2004, 29:2031-2038.
• [35]Newton PO, Upasani VV, Lhamby J, Ugrinow VL, Pawelek JB, Bastrom TP: Surgical treatment of main thoracic scoliosis with thoracoscopic anterior instrumentation. a five-year follow-up study. J Bone Joint Surg Am 2008, 90:2077-2089.
• [36]Yoon SH, Ugrinow VL, Upasani VV, Pawelek JB, Newton PO: Comparison between 4.0-mm stainless steel and 4.75-mm titanium alloy single-rod spinal instrumentation for anterior thoracoscopic scoliosis surgery. Spine 2008, 33:2173-2178.
• [37]Dang NR, Moreau MJ, Hill DL, Mahood JK, Raso J: Intra-observer reproducibility and interobserver reliability of the radiographic parameters in the spinal deformity study group’s AIS radiographic measurement manual. Spine 2005, 30:1064-1069.
• [38]Kuklo TR, Potter BK, Polly DW Jr, O’Brien MF, Schroeder TM, Lenke LG: Reliability analysis for manual adolescent idiopathic scoliosis measurements. Spine 2005, 30:444-454.
• [39]Dimar JR 2nd, Carreon LY, Labelle H, Djurasovic M, Weidenbaum M, Brown C, Roussouly P: Intra- and inter-observer reliability of determining radiographic sagittal parameters of the spine and pelvis using a manual and a computer-assisted methods. Eur Spine J 2008, 17:1373-1379.
• [40]Picetti GD 3rd, Ertl JP, Bueff HU: Endoscopic instrumentation, correction, and fusion of idiopathic scoliosis. Spine J 2001, 1:190-197.
• [41]Gatehouse SC, Izatt MT, Adam CJ, Harvey JR, Labrom RD, Askin GN: Perioperative aspects of endoscopic anterior scoliosis surgery: the learning curve for a consecutive series of 100 patients. J Spinal Disord Tech 2007, 20:317-323.
• [42]Kamimura M, Kinoshita T, Itoh H, Yuzawa Y, Takahashi J, Hirabayashi H, Nakamura I: Preoperative CT examination for accurate and safe anterior spinal instrumentation surgery with endoscopic approach. J Spinal Disord Tech 2002, 15:47-51.
• [43]Schick D: Computed tomography radiation doses for paediatric scoliosis scans. Internal report commissioned by Paediatric Spine Research Group from Queensland Health Biomedical Technology Services, Brisbane; 2004.
• [44]O’Brien MF, Kuklo TR, Blanke KM, Lenke LG: Radiographic Measurement Manual. Spinal Deformity Study Group (SDSG). Medtronic Sofamor Danek USA, Inc; 2008. Edition
• [45]Bernhardt M, Bridwell KH: Segmental analysis of the sagittal plane alignment of the normal thoracic and lumbar spines and thoracolumbar junction. Spine 1989, 14:717-721.
• [46]Boseker EH, Moe JH, Winter RB, Koop SE: Determination of “normal” thoracic kyphosis: a roentgenographic study of 121 “normal” children. J Pediatr Orthop 2000, 20:796-798.
• [47]Knight RQ, Jackson RP, Killian JT, Stanley EA, Lowe TG, Winter RB: SRS white paper on sagittal plane alignment. 2002. first accessed
• [48]de Jonge T, Dubousset JF, Illes T: Sagittal plane correction in idiopathic scoliosis. Spine 2002, 27:754-760.
• [49]Clement JL, Chau E, Kimkpe C, Vallade MJ: Restoration of thoracic kyphosis by posterior instrumentation in adolescent idiopathic scoliosis: comparative radiographic analysis of two methods of reduction. Spine 2008, 33:1579-1587.
• [50]Fletcher ND, Hopkins J, McClung A, Browne R, Sucato DJ: Residual thoracic hypokyphosis after posterior spinal fusion and instrumentation in adolescent idiopathic scoliosis: risk factors and clinical ramifications. Spine 2012, 37:200-206.
• [51]Bland JM, Altman DG: Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986, 1:307-310.
• [52]Bland JM, Altman DG: Applying the right statistics: analyses of measurement studies. Ultrasound Obstet Gynecol 2003, 22:85-93.
• [53]Suk SI, Lee SM, Chung ER, Kim JH, Kim SS: Selective thoracic fusion with segmental pedicle screw fixation in the treatment of thoracic idiopathic scoliosis: more than 5-year follow-up. Spine 2005, 30:1602-1609.
• [54]Abel MF, Herndon SK, Sauer LD, Novicoff WM, Smith JS, Shaffrey CI: Selective versus nonselective fusion for idiopathic scoliosis: does lumbosacral takeoff angle change? Spine 2011, 36:1103-1112.
• [55]Horton WC, Brown CW, Bridwell KH, Glassman SD, Suk SI, Cha CW: Is there an optimal patient stance for obtaining a lateral 36” radiograph? A critical comparison of three techniques. Spine 2005, 30:427-433.
• [56]Edwards CC 2nd, Lenke LG, Peelle M, Sides B, Rinella A, Bridwell KH: Selective thoracic fusion for adolescent idiopathic scoliosis with C modifier lumbar curves: 2- to 16-year radiographic and clinical results. Spine 2004, 29:536-546.
• [57]Patel PN, Upasani VV, Bastrom TP, Marks MC, Pawelek JB, Betz RR, Lenke LG, Newton PO: Spontaneous lumbar curve correction in selective thoracic fusions of idiopathic scoliosis: a comparison of anterior and posterior approaches. Spine 2008, 33:1068-1073.
• [58]Izatt MT, Adam CJ, Labrom RD, Askin GN: Relationship of deformity correction and clinical outcomes after thoracoscopic scoliosis surgery. A prospective series of 100 patients. Spine 2010, 35:E1577-E1585.
• [59]Adam CJ, Izatt MT, Harvey JR, Askin GN: Variability in Cobb angle measurements using reformatted computerized tomography scans. Spine 2005, 30:1664-1669.
• [60]Faro FD, Marks MC, Pawelek J, Newton PO: Evaluation of a functional position for lateral radiograph acquisition in adolescent idiopathic scoliosis. Spine 2004, 29:2284-2289.
• [61]Beauchamp M, Labelle H, Grimard G, Stanciu C, Poitras B, Dansereau J: Diurnal variation of Cobb angle measurement in adolescent idiopathic scoliosis. Spine 1993, 18:1581-1583.
• [62]Kiefer A, Shirazi-Adl A, Parnianpour M: Synergy of the human spine in neutral postures. Eur Spine J 1998, 7:471-479.
• [63]Shirazi-Adl A, El-Rich M, Pop DG, Parnianpour M: Spinal muscle forces, internal loads and stability in standing under various postures and loads–application of kinematics-based algorithm. Eur Spine J 2005, 14:381-392.