ABSTRACT
ABSTRACT Objective: To compare radiographic and surgical outcomes of Lenke 1B and 1C patterns. Methods: One hundred twenty patients with Lenke 1B and 1C scoliosis were grouped according to implant density as follows: low density (LD) of ≤1.4 and high density (HD) of >1.4. Matched subgroups (30 patients each) based on age, curve magnitude, and body mass index (BMI) were analyzed. Radiographic parameters were evaluated before operation, immediately after operation (ipo), and at 2 years' follow-up. SRS-30 was administered before operation and at 2 years' follow-up. Results: The major curves of the LD (n = 82) and HD groups (n=38) were respectively 59.1° and 65.6° before operation (p <.001), 26.3° and 22.9° ipo (p =.05), and 29.9° and 19.8° at 2 years' follow-up (p <.001). No significant differences in postoperative trunk shift and coronal balance were found (p =.69 and p =.74, respectively). The HD group had higher blood loss (p =.02), number of implants (p <.001), levels fused (p =.002), and surgical time (p <.001). The HD group had a higher prevalence of hypokyphosis from before operation to follow-up (p <.001). No significant differences were observed in the SRS-30 scores before operation and at 2 years' follow-up. The matched groups had similar preoperative major curves (p =.56), ages (p =.75), and BMIs (p =.61). Significantly longer surgical time (p =.009), higher density (p <.001), and better correction (p =.0001) were found in the HD group at 2 years' follow-up. No significant differences were found in the SRS-30 scores before operation and at 2 years' follow-up. Conclusion: LD constructs included fewer segments fused, lower intraoperative estimated surgical blood loss, and shorter operation time, and potentially decreasing complication risks due to fewer implants. Level of evidence III, Retrospective Cohort Study.
RESUMO Objetivo: Comparar os desfechos radiográficos e cirúrgicos da escoliose Lenke 1B e 1C. Métodos: Cento e vinte pacientes com escoliose Lenke 1B e 1C foram agrupados de acordo com a densidade do implante, como segue: baixa densidade (BD) de ≤ 1,4 e alta densidade (AD) de > 1,4. Foram analisados os grupos pareados (30 pacientes cada) com base na idade, magnitude da curva e índice de massa corporal (IMC). Os parâmetros radiográficos foram avaliados antes da cirurgia, no pós-operatório imediato (POI) e no acompanhamento de dois anos. O questionário SRS-30 foi administrado antes da cirurgia e no acompanhamento de dois anos. Resultados: As principais curvas dos grupos BD (n = 82) e AD (n = 38) foram respectivamente 59,1° e 65,6° antes da operação (p < 0,001), 26,3° e 22,9° no POI (p = 0,05) e 29,9° e 19,8° aos 2 anos de acompanhamento (p < 0,001). Não foram encontradas diferenças significantes no desvio do tronco e no balanço coronal no pós-operatório (p = 0,69 e p = 0,74, respectivamente). O grupo AD teve mais perda sanguínea (p = 0,02), número de implantes (p < 0,001), níveis de fusão (p = 0,002) e tempo de cirurgia (p < 0,001). O grupo AD teve maior prevalência de hipocifose do período anterior à cirurgia até o acompanhamento (p < 0,001). Não houve diferenças significantes nas pontuações do SRS-30 antes da operação e aos 2 anos de acompanhamento. No pré-operatório, os grupos pareados tinham curvas principais (p = 0,56), idade (p = 0,75) e IMC (p = 0,61) semelhantes. Constatou-se tempo cirúrgico expressivamente maior (p = 0,009), maior densidade (p < 0,001) e melhor correção (p = 0,0001) no grupo AD aos 2 anos de acompanhamento. Não foram encontradas diferenças significantes nas pontuações do SRS-30 antes da cirurgia e no acompanhamento de 2 anos. Conclusão: As estruturas de BD incluíram menos segmentos fundidos, menor perda de sangue intraoperatória estimada, menor tempo de cirurgia e menos risco de complicações, com possibilidade de redução, por causa do menor número de implantes. Nível de evidência III, Estudo retrospectivo de coorte.
ABSTRACT
Background@#The effect of short-segment decompression/fusion versus long-segment decompression/fusion and osteotomy for Lenke-Silva type VI adult degenerative scoliosis (ADS) has not been clarified. This study aimed to compare the clinical and radiographic results of short-segment fusion vs. long-segment fusion and osteotomy for patients with Lenke-Silva type VI ADS.@*Methods@#Data of 28 patients who underwent spinal surgery for ADS from January 2012 to January 2014 in the General Hospital of Northern Theater Command were reviewed. Of the 28 patients, 12 received long-segment fusion and osteotomy and 16 received short-segment fusion. Radiographic imaging parameters and clinical outcomes, including the sagittal vertical axis (SVA), lumbar lordosis (LL) angle, pelvic tilt (PT), sacral slope (SS), the visual analog scale (VAS), Japanese Orthopedic Association (JOA), Oswestry disability index (ODI), and lumbar stiffness disability index (LSDI) scores, were recorded. The difference between groups was compared using the dependent t test or Chi-squared test.@*Results@#The Cobb and LL angles and SVA improved in both groups; however, PT and SS angles did not improve following short fusion. There were significant differences in the post-operative SVA (26.8 ± 5.4 mm vs. 47.5 ± 7.6 mm, t = -8.066, P < 0.001), PT (14.7 ± 1.8° vs. 29.1 ± 3.4°, t = -13.277, P < 0.001), and SS (39.8 ± 7.2° vs. 26.1 ± 3.3°, t = 6.175, P < 0.001) between the long and short fusion groups. All patients had improved ODI, JOA, and VAS scores post-operatively (all P < 0.001), with no significant difference between the groups (all P > 0.05). The post-operative LSDI score was 3.5 ± 0.5 in the long fusion group, which was significantly higher than that of the short fusion group (1.4 ± 0.7; P < 0.001).@*Conclusions@#The clinical outcomes of patients with Lenke-Silva type VI ADS who underwent short-segment decompression/fusion were comparable to those of patients who underwent long-segment decompression/fusion and osteotomy despite poor correction of sagittal imbalance. Moreover, short-segment decompression/fusion showed a short operation time and reduced surgical trauma.
ABSTRACT
Objective: To investigate the short-term effectiveness of proximal fixation of one vertebra above to the upper end vertebra and the upper end vertebra in the treatment of Lenke type 1 adolescent idiopathic scoliosis (AIS) patients with preoperative right higher shoulder. Methods: The clinical data of 37 Lenke type 1 AIS patients treated with posterior correction between January 2010 and December 2015 were retrospectively analysed. According to proximal fixation vertebra, the patients were divided into 2 groups: group A ( n=17), proximal fixation of one vertebra above to the upper end vertebra; group B ( n=20), proximal fixation of the upper end vertebra. There was no significant difference in gender, age, Risser stage, radiographic shoulder height (RSH), flexibility of proximal thoracic curve, flexibility of main thoracic curve, flexibility of thoracolumbar/lumbar curve between 2 groups ( P>0.05). The main thoracic curve Cobb angle, proximal thoracic curve Cobb angle, thoracolumbar/lumbar curve Cobb angle, apical vertebral translation (AVT), clavicle angle (CA), RSH, coronal trunk shift, sagittal trunk shift, thoracic kyphosis (TK), and lumbar lordosis (LL) were measured by X-ray film before operation, and at 1 month, 1 year, and 2 years after operation. The correction indexes of main thoracic curve were evaluated, including the correction degree and correction rate of main thoracic curve and AVT correction at 1 month after operation, the loss degree and the loss rate of the correction of main thoracic curve at 2 years after operation. Results: The operation time and intraoperation blood loss in group A were significantly greater than those in group B ( P0.05). Comparison within the two groups: except for LL had no significant difference between pre- and post-operation ( P>0.05), the other indicators were significantly improved after operation ( P0.05), and there was no significant loss during follow-up. Comparison between the two groups: there was no significant difference in all the radiographic indexes at pre- and post-operation ( P>0.05). Conclusion: For Lenke type 1 AIS patients with preoperative right high shoulder, proximal fixation vertebra be fixed to the upper end vertebral can obtain satisfactory short-term orthopedic effectiveness and reduce blood loss and operation time.
ABSTRACT
Objective To study the correlation between the deformation and displacement trend of the lumbosacral vertebra (L1-S1) for two typical scoliosis spines under vertical loads,so as to provide the mechanical basis of treatment and prevention of scoliosis in clinic.Methods The X-ray computed tomography (CT) images of two typical scoliosis spines (Lenke-4AN type and Lenke-5CN type) were converted into 3D models,and their finite element models were then established and verified.The internal stress distribution and displacement variation of the models were calculated by the finite element software;the correlation between the lumbosacral vertebral structure and displacement of the spine was analyzed.Results Under the same boundary conditions and load cases,the stress and displacement for two kinds of lumbosacral vertebral models showed different trends.Due to its leftleaning and forward convex bending deformation as well as the relatively large lordosis angle (60°) and smaller left-leaning angle (17.37°),the Lenke-4AN type lumbosacral spine produced slightly small forward convex displacement (8.18 mm) and relatively large left-leaning displacement (0.97 mm).The Lenke-5CN type lumbosacral spine showed left-leaning and forward convex bending deformation as well,with relatively large lordosis angle(59°) and left-leaning angle (26.97°),so it produced more severe left-leaning displacement (20.65 mm) andforward convex displacement (9.22 mm).Conclusions The deformation trend of lumbosacral vertebra is closelyrelated to its structural characteristics,and different scoliosis lumbosacral vertebral structures will cause the corre-sponding deformation trend.The research findings are important for the prevention and treatment of scoliosis.
ABSTRACT
Objective To study the correlation between the deformation and displacement trend of the lumbosacral vertebra (L1-S1) for two typical scoliosis spines under vertical loads,so as to provide the mechanical basis of treatment and prevention of scoliosis in clinic.Methods The X-ray computed tomography (CT) images of two typical scoliosis spines (Lenke-4AN type and Lenke-5CN type) were converted into 3D models,and their finite element models were then established and verified.The internal stress distribution and displacement variation of the models were calculated by the finite element software;the correlation between the lumbosacral vertebral structure and displacement of the spine was analyzed.Results Under the same boundary conditions and load cases,the stress and displacement for two kinds of lumbosacral vertebral models showed different trends.Due to its leftleaning and forward convex bending deformation as well as the relatively large lordosis angle (60°) and smaller left-leaning angle (17.37°),the Lenke-4AN type lumbosacral spine produced slightly small forward convex displacement (8.18 mm) and relatively large left-leaning displacement (0.97 mm).The Lenke-5CN type lumbosacral spine showed left-leaning and forward convex bending deformation as well,with relatively large lordosis angle(59°) and left-leaning angle (26.97°),so it produced more severe left-leaning displacement (20.65 mm) andforward convex displacement (9.22 mm).Conclusions The deformation trend of lumbosacral vertebra is closelyrelated to its structural characteristics,and different scoliosis lumbosacral vertebral structures will cause the corre-sponding deformation trend.The research findings are important for the prevention and treatment of scoliosis.
ABSTRACT
Objective To study the correlation between the deformation and displacement trend of the lumbosacral vertebra (L1-S1) for two typical scoliosis spines under vertical loads,so as to provide the mechanical basis of treatment and prevention of scoliosis in clinic.Methods The X-ray computed tomography (CT) images of two typical scoliosis spines (Lenke-4AN type and Lenke-5CN type) were converted into 3D models,and their finite element models were then established and verified.The internal stress distribution and displacement variation of the models were calculated by the finite element software;the correlation between the lumbosacral vertebral structure and displacement of the spine was analyzed.Results Under the same boundary conditions and load cases,the stress and displacement for two kinds of lumbosacral vertebral models showed different trends.Due to its leftleaning and forward convex bending deformation as well as the relatively large lordosis angle (60°) and smaller left-leaning angle (17.37°),the Lenke-4AN type lumbosacral spine produced slightly small forward convex displacement (8.18 mm) and relatively large left-leaning displacement (0.97 mm).The Lenke-5CN type lumbosacral spine showed left-leaning and forward convex bending deformation as well,with relatively large lordosis angle(59°) and left-leaning angle (26.97°),so it produced more severe left-leaning displacement (20.65 mm) andforward convex displacement (9.22 mm).Conclusions The deformation trend of lumbosacral vertebra is closelyrelated to its structural characteristics,and different scoliosis lumbosacral vertebral structures will cause the corre-sponding deformation trend.The research findings are important for the prevention and treatment of scoliosis.
ABSTRACT
Objective To study correlation between the deformation and displacement trend of the lumbosacral vertebra (L1-S1) for two typical scoliosis spine under vertical load, so as to provide the mechanical basis of treatment and prevention of scoliosis in clinic. Methods The X-ray computed tomography (CT) imaging of two typical scoliosis spine (Lenke-4AN type and Lenke- 5CN type) were converted into 3D models，and their finite element models were then established and verified. The internal stress distribution and displacement variation of the models were calculated by the finite element software; the correlation between the lumbosacral vertebral structure and displacement of the spine was analyzed. Results Under the same boundary conditions and load cases, the stress and displacement for two kinds of lumbosacral vertebral models showed different trends. Due to its left-leaning and forward convex bending deformation as well as relatively large lordosis angle(60°) and smaller left-leaning angle (17.37°), the Lenke-4AN type lumbosacral spine produced slightly small forward convex displacement(8.18 mm) and relatively large left-leaning displacement (0.97 mm). The Lenke- 5CN type lumbosacral spine showed left-leaning and forward convex bending deformation as well, with relatively large lordosis angle (59°) and left-leaning angle (26.97°), so it produced more severe left-leaning (20.65 mm) and forward deformation (9.22 mm). Conclusions The deformation trend of lumbosacral vertebra is closely related to its structural characteristics, and different scoliosis lumbosacral vertebral structures will cause corresponding deformation trend. The research findings are important for the prevention and treatment of scoliosis.
ABSTRACT
Introducción: El balance sagital es crítico para los resultados a largo plazo en el manejo quirúrgico de la escoliosis idiopática del adolescente. La cifosis de unión se podría definir como un hallazgo radiológico en la transición de la columna fusionada y la columna móvil en pacientes asintomáticos. El objetivo de este trabajo fue comparar la cifosis de unión proximal posoperatoria en curvas Lenke 5C con dos técnicas quirúrgicas distintas: la instrumentación anterior y la instrumentación posterior. Materiales y Métodos: Estudio retrospectivo, controlado no aleatorizado, de 37 pacientes con escoliosis idiopática del adolescente, curvas Lenke 5C con fusión corta, de vértebra límite a vértebra límite. Grupo 1: 18 pacientes con artrodesis anterior instrumentada y Grupo 2: 19 pacientes con artrodesis posterior instrumentada. Los parámetros sagitales radiológicos medidos fueron: 1) línea de plomada de C7, 2) cifosis de unión, 3) cifosis torácica, 4) lordosis lumbar, con un seguimiento mínimo de 2 años. Resultados: Grupo 1: aumento de la cifosis de unión entre el preoperatorio y el seguimiento a los 2 años de 6,27° (p = 0,0002). La incidencia de cifosis de unión patológica fue del 17 por ciento. Grupo 2: aumento de la cifosis de unión entre el preoperatorio y el seguimiento de 4,63° (p = 0,0004). La incidencia de cifosis de unión patológica fue del 16 por ciento. Conclusión: No hubo diferencias significativas entre ambos grupos en la incidencia de cifosis de unión patológica.
Background: Sagittal balance is critical for long-term results in the surgical handling of adolescent idiopathic scoliosis. Proximal junctional kyphosis could be defined as a radiographic findings in the fused and mobile spine transition in asymptomatic patients. Objective: To compare post-surgical proximal junctional kyphosis in Lenke C5 curves with two different surgical techniques: anterior and posterior instrumentation. Methods: Retrospective, controlled, non-randomized study of 37 patients with Lenke C5 adolescent idiopathic scoliosis, with short fusion from end-vertebra to end-vertebra. Group 1: 18 patients with anterior instrumented arthrodesis, and Group 2: 19 patients with posterior instrumented arthrodesis. The radiographic sagittal parameters measured were: 1) plumbline from the C7, 2) junctional kyphosis, 3) thoracic kyphosis, and 4) lumbar lordosis; with a minimum follow-up of two years. Results: Group 1: increase of junctional kyphosis between the preoperative period and a two-year follow-up, 6.27° (p = 0.0002). The incidence of pathologic junctional kyphosis was 17%. Group 2: increase of junctional kyphosis between the preoperative period and the follow- up, 4.63° (p = 0.0004). The incidence of pathologic junctional kyphosis was 16%. Conclusion: There were no significant differences between groups in the incidence of pathologic junctional kyphosis.
Subject(s)
Humans , Male , Female , Adolescent , Spinal Curvatures/surgery , Scoliosis/surgery , Spinal Fusion/instrumentation , Spinal Fusion/methods , Lumbar Vertebrae/surgery , Thoracic Vertebrae/surgery , Follow-Up Studies , Incidence , Retrospective Studies , Treatment OutcomeABSTRACT
OBJETIVO: Identificar los factores de riesgo de descompensación distal postoperatoria (D.D.P.) y definir una estrategia quirúrgica segura en curvas tipo Lenke 1A tratadas con tornillos pediculares. MÉTODO: Estudio radiológico retrospectivo de 63 pacientes con escoliosis Lenke 1A, con un seguimiento mínimo de un año. Se evaluó, edad, sexo, grados Cobb, signo de Risser, relación de la vértebra distal instrumentada (V.D.I.) con la vértebra distal de la curva (V.D.), vértebra estable (V.E.) y con la vértebra, cuya distancia a la línea central vertical al sacro (L.V.S.) era superior a 10 mm "distancia vertebral" (D.V.). RESULTADOS: 8 casos (12,7%) desarrollaron D.D.P. El signo de Risser fue 0 en 2 pacientes (25%) y I en 2 pacientes (25%). Relación de V.D.I. con V.D.: 4 pacientes (50%) mismo nivel (V.D. +0), 4 pacientes (50%) un nivel caudal (V.D. (+1); relación V.D.I. con V.E.: 5 pacientes (62,5%) 2 niveles cefálicos (V.E -2), 3 pacientes (37,5%) 1 nivel cefálico (V. E.-1); relación V.D.I. con D.V.: 5 pacientes (62,5%) un nivel cefálico D.V. (-1), 3 pacientes mismo nivel (D.V.+ 0). CONCLUSIONES: Riesgo de descompensación distal postoperatoria: V.D.I. mismo nivel V.D. (V.D. + 0), 2 niveles cefálicos V.E. (V.E.-2), 1 nivel cefálico D.V. (D.V. -1). Estrategia quirúrgica curvas Lenke 1A: V.D.I: 1/2 niveles caudales a V.D. (V.D. +1/+2), un nivel cefálico a V.E. (V.E -1), mismo nivel D.V. (D.V. +0).
OBJETIVO: Identificar os fatores de risco de descompensação distal pós-operatória (DDP) e definir estratégia cirúrgica de segurança em curvaturas de Lenke 1A, tratadas com parafusos pediculares. MÉTODO: Estudo radiológico retrospectivo de 63 pacientes com escoliose Lenke 1A, com acompanhamento mínimo de um ano. Os parâmetros avaliados foram idade, sexo, graus do ângulo de Cobb, sinal de Risser, relação da vértebra distal instrumentada (VDI) com a vértebra distal da curvatura (VD), com a vértebra estável (VE) e com a vértebra cuja distância da linha central vertical até o sacro (LVS) era superior a 10 mm de "distância vertebral" (DV). RESULTADOS: 8 casos (12,7%) desenvolveram DDP. O sinal de Risser foi 0 em 2 pacientes (25%) e 1 em 2 pacientes (25%). Relação VDI/VD: 4 pacientes (50%) mesmo nível (VD +0), 4 pacientes (50%) nível caudal (VD +1); relação VDI/VE: 5 pacientes (62,5%) 2 níveis cefálicos (VE -2), 3 pacientes (37,5%) 1 nível cefálico (VE -1); relação VDI/DV: 5 pacientes (62,5%) um nível cefálico DV (-1), 3 pacientes mesmo nível (DV +0). CONCLUSÕES: Risco de descompensação distal pós-operatória:VDI mesmo nível VD (VD +0), 2 níveis cefálicos VE (VE -2), 1 nível cefálico DV (DV -1). Estratégia cirúrgica nas curvaturas Lenke 1A: VDI: 1/2 níveis caudal até VD (VD +1/+2), um nível cefálico até VE (VE -1), mesmo nível DV (DV +0).
OBJECTIVE: To identify risk factors for postoperative distal decompensation (PDD) and safe surgical strategy in curvatures Lenke type 1A, treated with pedicle screws. METHOD: Retrospective radiographic study of 63 patients with scoliosis Lenke 1A, with follow-up of at least one year. The parameters evaluated were age, sex, degrees of Cobb's angle, Risser sign, relationship of distal instrumented vertebra (DIV) to the distal vertebra (DV) of the curvature, to the stable vertebra (SV) and to the vertebra which distance to the central vertical line to the sacrum (VLS) was greater than 10 mm of "vertebral distance" (VD). RESULTS: 8 cases (12.7%) developed DDP. The Risser sign was 0 in 2 patients (25%) and 1 in 2 patients (25%). DIV/DV relationship: 4 patients (50%) same level (DV +0), 4 patients (50%) caudal level (DV +1); DIV/SV ratio: 5 patients (62.5%) 2 cephalic levels (VD -2), 3 patients (37.5%) 1 cephalic level (SV -1); DIV/VD relationship: 5 patients (62.5%) 1 cephalic level (VD -1), 3 patients the same level (VD +0). CONCLUSIONS: Risk of postoperative distal decompensation: DIV same level DV (DV +0), 2 cephalic levels SV (SV -2), 1 cephalic level VD (VD -1). Surgical strategy in Lenke 1A curvatures: DIV: 1-2 levels caudal to DV (DV +1/+2), 1 cephalic level to SV (SV -1), the same level VD (VD +0).
Subject(s)
Adolescent , Bone Screws , General Surgery , ScoliosisABSTRACT
[Objective]To determine the prevalence of each type of adolescent idiopathic scoliosis in Lenke classification,and find out the relationship between Lenke classification and fusion level. [Method]Totally 154 cases of adolescent idiopathic scoliosis being treated with sugery between January 2002 and September 2007 were analyzed retrospectively in Guangdong General Hospital.All casess were classified with Lenke classification,prevalence of each type were counted.The fusion levels were compared with Lenke classification.[Result]All of 154 cases could be classified by Lenke classification,the 5 most common types were 1AN,5CN,1BN,2AN,1CN.95.5% of structural curve had been fused.[Conclusion]Lenke classification can provide effective guidance for pre-operative evaluation and choosing opertive method.The method of determining structural curve is useful.
ABSTRACT
[Objective]To compare spontaneous correction of the unfused thoracic curves after selective anterior versus posterior fusion in Lenke5 adolescent idiopathic scoliosis(AIS). [Method]A total of 72 Lenke5 AIS patients were rescruited from May 1997 to October 2005.Out of them,40 received selective anterior fusion(group A) and 32 received selective posterior fusion(group B).All had a minimum of 2-year follow-up.[Result] No complication were found in both groups at the latest follow-up.The thoracic curve was corrected from 30? to 16? for group A,33? to 18? for group B.Both groups had a better spontaneous correction of the unfused thoracic curves.The correction rate had no significant difference between groups.However,the thoracic curve was increased in four patients(2 in each group;group C),which resulted in trunk imbalance.The thoracolumbar/lumbar thoracic(TL/L:T) Cobb's ratio averaged 1.09 in the four patients whereas 1.59 in other 68 patients(group D).The flexibility of the thoracic curve had significant difference in group C and D(34.2% vs 57.3%).[Conclusion]Both of the surgical treatments can get a better spontaneous correction of the unfused thoracic curves.It is important to evaluate the.thoracolumbar/lumbar–thoracic(TL/L:T) Cobb's ratio and the flexibility of the thoracic curve before selective fusion.
ABSTRACT
OBJECTIVE: The authors investigated the efficacy of the calcium sulfate(OsteoSet(r) pellets) as an autograft extender when used to perform posterolateral lumbar fusions. PATIENTS AND METHODS: Twenty patients who underwent lumbar posterolateral arthrodesis for various spinal diseases between October 1999 and March 2000 were evaluated. Arthrodesis was performed by transpedicular screw fixation and bone grafting with a mixture of autograft + calcium sulfate in a 1:1 ratio. At time intervals of 1, 2, 3, and 6 months, postoperative radiographs were obtained to review the resorption of calcium sulfate and the evidence of fusion. A modified Lenke scale was used to assess the status of the fusion. RESULTS: At 2 months after operation, the average modified Lenke scale score for the OsteoSet(r) pellets group was 3.8. However at 6 months after operation, the average modified Lenke scale score for the OsteoSet(r) pellets group was 1.8. Resorption of calcium sulfate pellets was revealed in all cases at 6 months after surgery. CONCLUSION: It is presumed that a combination of calcium sulfate and autograft can play a role as an effective autograft extender in the posterolateral spinal fusion.