| Chapter 2(Section 1)Can acetabular orientation be restored by lumbar pedicle subtraction osteotomy in ankylosing spondylitis patients with thoracolumbar kyphosis?Objective:To evaluate whether acetabular orientation(abduction and anteversion)can be restored by lumbar pedicle subtraction osteotomy(PSO)in ankylosing spondylitis(AS)patients with thoracolumbar kyphosis.Materials and methods:A total of 33 consecutive AS patients with thoracolumbar kyphosis undergoing one-level lumbar PSO were retrospectively reviewed.Radiographical measurements included sagittal vertical axis,global kyphosis,thoracic kyphosis,local kyphosis,lumbar lordosis,pelvic incidence,sacral slope,and pelvic tilt.Acetabular abduction and anteversion were measured on CT scans of the pelvis before and after lumbar PSO.The preoperative and postoperative parameters were compared by the paired samples t test.Pearson’s correlation analysis was conducted to determine the correlations between the changes in acetabular abduction and anteversion and the changes in sagittal spinopelvic parameters.Results:After lumbar PSO,sagittal vertical axis,global kyphosis,and pelvic tilt were corrected from 15.7 cm ± 6.7 cm,66.8° ± 17.5°,and 38.60±9.0° to 2.9 cm ± 4.9 cm,21.3° ± 8.2°,and 23.2° ± 8.2°,respectively(P<0.001).Of note,acetabular abduction and anteversion were decreased from 59.6° ± 4.6° and 31.4° ± 6.5° before surgery to 51.4° ± 6.5± and 20.2± ° 4.4± after surgery,respectively(P<0.001),Moreover,the changes in acetabular abduction and anteversion were observed significantly correlated with the change in pelvic tilt(r = 0.527,p = 0.002;r = 0.586,P<0.001).Conclusions:Abnormal acetabular abduction and anteversion could be corrected by lumbar PSO in AS patients with thoracolumbar kyphosis.Consequently,a relatively normal acetabular orientation could be achieved after lumbar PSO,which might decrease the potential risk of dislocation in AS patients with spine and hip deformities requiring subsequent THR surgery.Chapter 2(Section 2)Does thoracolumbar kyphosis correction change the acetabular cup anteversion in ankylosing spondylitis patients with a previous total hip replacement?Objective:To investigate whether thoracolumbar kyphosis correction affected acetabular cup anteversion(ACA)in ankylosing spondylitis(AS)patients with a previous total hip replacement(THR).Materials and methods:AS patients with thoracolumbar kyphosis who already had undergone THR surgery prior to the spinal osteotomy were included.ACA and anterior pelvic plan(APP)were measured before and after the spinal correction surgery.Spinopelvic parameters were also measured including:sagittal vertical axis(SVA),global kyphosis(GK),thoracic kyphosis(TK),lumbar lordosis(LL),pelvic incidence(PI),pelvic tilt(PT),and sacral slope(SS).Radiographical parameters before and after surgery were compared using the paired t-tests.The correlations between spinopelvic parameters and ACA and APP were calculated via Pearson correlation coefficients.Results:Fourteen AS patients undergoing spinal deformity correction after THR surgery(twenty-three hips)were included.ACA and APP significantly reduced from 23.1°±7.2°and 33.1°±10.0° before surgery to 9.9°± 4.4°and 16.2°±8.3°after surgery(P<0.001).SVA,GK,LL,PT,and SS were significantly corrected from 18.9± 4.8cm,73.6° ± 16.9°,18.7° ± 12.4°,41.5° ± 9.6°,and 3.6°× 4.6°preoperatively to 4.6 ± 2.5cm,27.5°± 12.5°,-25.4°± 9.0°,25.8°± 8.2°,and 18.3°±5.1°postoperatively(P<0.001).The change in ACA strongly correlated with the change in PT(r = 0.874,P<0.001).Conclusions:A high prevalence of excessively anteverted acetabular component was observed in AS patients with a previous THR.Spinal osteotomy procedure can not only reconstruct the sagittal alignment but also decrease ACA,which may theoretically decrease the risk of anterior hip prosthesis dislocation after THR.Chapter 2(Section 3)Does hip involvement negatively impact postoperative radiographic outcomes in ankylosing spondylitis patients with thoracolumbar kyphosis after lumbar pedicle subtraction osteotomy?Objective:The aim of the study was to identify whether hip involvement will negatively impact postoperative radiographic outcomes in AS patients with thoracolumbar kyphosis after lumbar PSO.Materials and methods:From March 2009 to June 2013,a total of 44 consecutive AS patients with thoracolumbar kyphosis who underwent one-level lumbar PSO were retrospectively reviewed.All the patients had more than 2-year follow-up.Hip involvement was evaluated based on the Bath ankylosing spondylitis radiology index-hip(BASRI-hip)and defined by a score of at least 2.All patients were divided into group A(patients without hip involvement)and group B(patients with hip involvement).Radiographical measurements included sagittal vertical axis(SVA),global kyphosis(GK),thoracic kyphosis(TK),local kyphosis(LK),lumbar lordosis(LL),pelvic incidence(PI),pelvic tilt(PT),and sacral slope(SS).The sagittal parameters after surgery and at the last follow-up were compared with those before surgery by the paired-samples t test.Student’s t tests were used to evaluate the differences of the sagittal parameters between the two groups before surgery and at the last follow-up.Results:The preoperative SVA and PT was not significantly different between group A and group B(SVA:14.0± 6.3cm vs.14.7±6.0cm,P>0.05;PT:36.8°±7.1°vs.37.3°±7.7°,P>0.05),and both groups had similar magnitudes of kyphosis corrections(LK correction:44.9° ± 4.9° vs.44.2° ± 8.3°,P>0.05).However,group B had significantly larger SVA and PT than group A(SVA:7.6 ± 4.5cm vs.3.5 ±3.4cm,P<0.05;PT:28.1°± 8.6°vs.19.0°±8.0°,P<0.05)at the last follow-up.Conclusions:In AS patients with thoracolumbar kyphosis,hip involvement lead to insufficient correction of SVA and PT after lumbar PSO,which negatively impact postoperative radiographic outcomes.Chapter 2(Section 4):Can pelvic tilt be predicted by the sacro-femoral-pubic angle in ankylosing spondylitis patients with thoracolumbar kyphosis?Objective:To construct a predictive model for pelvic tilt(PT)based on the sacro-femoral-pubic angle(SFP angle),and to evaluate the effectiveness of the predictive model in ankylosing spondylitis(AS)patients with thoracolumbar kyphosis.Materials and methods:From October 2008 to June 2013,115 AS patients(98 males and 17 females)with thoracolumbar kyphosis were included in this study.Full-length antero-posterior and lateral spine radiographs were available,and all spinal and pelvic anatomic landmarks(pelvis and femoral heads)could be clearly identified.PT,SFP angle and global kyphosis(GK)were measured.The patients were randomly divided into group A(n = 65)and group B(n = 50).In group A,the predictive model for PT was constructed by the results of the linear regression analysis.In group B,the predictive ability and accuracy of the predictive model were investigated.Results:In group A,the Pearson correlation analysis revealed a strong correlation between the SFP angle and PT(r = 0.852,P<0.001).The predictive model for PT was constructed as PT = 72.3-0.82 ×(SFP angle).In the validation group(group B),PT was predicted by the model with a mean error of 4.6°(SD = 4.5°),and the predictive ability was 78%in the range of±5°.Conclusions:PT can be accurately predicted by the SFP angle using the current model:PT = 72.3-0.82 ×(SFP angle),when the femur heads are poorly visualized on lateral film in AS patients with thoracolumbar kyphosis.Chapter 3(Section 1)Correlation analysis of spinopelvic parameters and quality of life in the adult deformity patients over 60-year-oldObjectives:To investigate the correlations of spinopelvic parameters and quality of life in the adult deformity patients over 60-year-old.Materials and Methods:From March 2014 to May 2016,43 adult deformity patients(scoliosis with a Cobb angle of ≥20°,sagittal vertical axis of>5 cm,or pelvic tilt of≥25°)over 60-year-old were included,consisting of 12 adult degenerative scoliosis patients,7 adult degenerative kyphosis patients,12 adult degenerative kyphoscoliosis patients,6 adult idiopathic scoliosis patients,1 adult idiopathic kyphoscoliosi patients,and 5 post-traumatic kyphosis patients.There were 7 males and 36 females,with an average age of 64.0 士 3.5 years(range,.0-73.0 years).Scoliosis Research Society(SRS)-22,Oswestry Disability Index(ODI)questionnaires and the visual analog scale(VAS)for back and leg pain were used to evaluate the quality of life of the adult deformity patients over 60-year-old.Spinopelvic parameters were measured on standing lateral full-spine radiographs,including:sagittal vertical axis(SVA),thoracic kyphosis(TK),lumbar lordosis,(LL),pelvic incidence(PI),pelvic tilt(PT),sacral slope(SS),and T1 pelvic angle(TPA).In addition,the values of PI-LL were calculated.Pearson correlation was used to evaluate the relationships of the sagittal parameters and the quality of life in the adult deformity patients over 60-year-old.Results:The scores of Function,Pain,Self-image,Mental health,and Sub-total in the SRS-22 questionnaire were 13.4 ± 2.1,17.3 ± 2.7,13.2 ± 3.0,15.7 ± 11.8,and 59.6 ±5.6.The average scores of ODI,VAS back,and VAS leg were 46.8 ± 17.8,5.7 ± 2.6,and 3.9±3.0.The mean values of SVA、TK、LL、PI、PT、SS、TPA,and PI-LL were 6.5±6.2cm、12.7 ± 15.8°、-16.9 ± 17.2°、49.0 ± 12.3°、30.2 ± 11.6°、18.8±10.6°、28.8 ± 14.4° and 32.1 ± 17.8。Pearson correlation analysis showed SVA and TPA correlated with the score of function,pain,self-image,sub-score of SRS-22,ODI,VAS back pain(r =-0.386,-0.375,-0.361,-0.410,0.445,0.389,P<0.05;r=-0.403,-0.426,-0.466,-0.425,0.512,0.465,P<0.05).LL,PT and PI-LL were correlated with ODI and VAS back pain(r = 0.368,0.367,P<0.05;r = 0.376,0.341,P<0.05;r ＝ 0.401,0.395,P<0.05).Conclusion:In the adult deformity patients over 60-year-old,increased SVA and TPA can affect the function,self-image and back pain.Decreased LL,increased PT,and increased PI-LL can aggravate the back pain of the patients.TPA can both represent the sagittal alignment of the spine and pelvis,which was correlated most strongly with the quality of life in patients.Chapter 3(Section 2):Correlation analysis of lumbar syndesmophytes,global kyphosis and quality of life in ankylosing spondylitis patientsObjectives:To investigate the correlations of lumbar syndesmophytes,global kyphosis and quality of life in ankylosing spondylitis(AS)patients.Materials and Methods:From April 2011 to October 2014,106 AS patients were included.There were 98 males and 8 females,with an average age of 36.4 years(range,20～64 years).The clinical data consisted of age,age of onset,disease duration,global kyphosis(GK),Stoke ankylosing spondylitis spinal score(SASSS),Oswestry disability index(ODI),Bath ankylosing spondylitis disease activity index(BASDAI),Bath ankylosing spondylitis functional index(BASFI),erythrocyte sedimentation rate(ESR)and C-reaction protein(CRP).The subjects were divided into group A and group B according to SASSS(Group A:SASSS ≤36;Group B:SASSS>36).The differences of the parameters between group A and group B were analyzed by the independent t-test.Pearson correlation was used to evaluate the relationships of clinical parameters and to investigate the risk factors correlated with SASSS.Results:Age,disease duration,GK and BSFI were observed obviously different in group A and group B.Age,disease duration,GK,ODI and BASFI were found significantly correlated with SASSS.Disease duration,SASSS,and GK were remarkably correlated with ODI and BASFI.Conclusions:Older age,longer disease duration and larger GK were high risk factors of SASSS in AS patients.The quality of life in AS patients were severely affected by the longer disease duration,higher SASSS,and larger GK. |
