Sequential correction: a reliable and simple technique for complex spine deformity / 中华骨科杂志

Based on the coronal balance classification for adult spinal deformity established by our center, a new surgical technique for adult spinal deformity was further proposed, namely Sequential Correction. Spine deformity was classified as thoracolumbar/lumbar type and lumbosacral type according to the driver of the deformity. A short rod was firstly installed to correct the driver, followed by another short rod installed on the other side, and two long rods were installed at last. The incidence of postoperative coronal imbalance was significantly reduced using sequential correction, and the correction rate was significantly improved compared with the traditional technique.

Changing pelvic incidence with the anatomical morphology during adolescence / 中华骨科杂志

Objective To evaluate the changing pattern of pelvic incidence (PI) during peak skeleton growth in adolescence and to study whether PI is associated with the anatomical morphology changes of pelvis and sacrum.Methods This retrospective longitudinal study recruited adolescent idiopathic scoliosis (AIS) patients,age between 9 and 18 years with full spine images and have at least 3 times' follow-up.The radiological anatomical parameters were measured in each follow-up including PI,pelvic height (PH),pelvic width (PW),sacral width (SW),femoral head-sacrum (FH-S),sacrum-coccyx (S-C) length,sacrum-coccyx (S-C) distance and sacral curvature ratio.△Parameter and growth velocity of each parameters were calculated.According to the skeletal maturity,all subjects were divided into 3 groups:Low Risser Group (first visit at Risser 0 and follow up through Risser 0 to 1),Moderate Risser Group (first visit at Risser 1 and follow up through Risser 1 to 3) and High Risser group (first visit at Risser 3 and follow up through Risser 3 to 5).Each group has 106 patients.We increased the male ratio to detect the gender difference.A total of 318 AIS patients were included in our study and there are 117 male patients.Descriptive analysis was conducted on the sample age,gender and measured parameter values with mean and standard deviation (SD).The intra-and inter-observer reliability analysis,and the intraclass correlation coefficient (ICC) were calculated.The correlation between △PI and △parameter was evaluated by calculating Pearson correlation coefficient R value.Results The mean age of all subjects was 12.86 years and the mean Cobb angle was 26.67° at first visit.The peak growth velocity of PI was in Risser I (female 1.5°/year and male 1.6°/year).The PI was also increasing rapidly in Risser 0.5 (female 1.2°/year and male 1.5°/year) and Risser 2 (female 1.1°/year and male 1.4°/year).When the Risser grade reached 3 which was a sign of the end of skeleton growth,the PI still had increasing potential and it increased slower in Risser 4 and Risser 5.There showed significant correlation between △PI and △age in the three group(P＜0.05)and the correlation was stronger in Low Risser group and Moderate Risser group than that in High Risser group.There showed significant correlation between △PW and △PI in all groups while △PH and △PI showed correlation only in Low Risser group.There showed significant correlation between △SW and △PI,△FH-S and △PI,△S-C length and △PI (P＜0.05) except △S-C length in male Low Risser group and △FH-S in female High Risser group and the Moderate Risser group had the strongest correlation.The △S-C distance and △S-C ratio didn't show any correlation with △PI (P＜0.05) expect the male of High Risser group.Conclusion Pelvic incidence is increasing during skeleton growth at the age of 9 to 17.It has the peak growth velocity in Risser 1 and remains growth potential in Risser 5.PI growth is correlated with pelvic height,femoral head-sacrum distance,pelvic width and sacral width.

Restoration of the difference value of pelvic incidence and lumbar lordosis in degenerative scoliosis patients: its influence in maintaining sagittal profile and improving quality of life / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the role that post-operative difference value of pelvic incidence and lumbar lordosis (PI-LL) played on loss of correction, implant failure and health-related quality of life during follow-up in degenerative scoliosis patients.</p><p><b>METHODS</b>Retrospective review of 62 patients (average age (57 ± 10) years, 11 male and 51 female patients) with degenerative scoliosis who underwent one stage posterior surgical instrumentation in the affiliated Drum Tower Hospital of Nanjing University Medical School from January 2005 to December 2011. The mean follow-up duration was 4.2 years. Long-cassette standing upright sagittal radiographs were obtained before and after operation and at the last follow-up. At the last follow-up, visual analogue scale and Oswestry disability index were collected. Based on post-operative PI-LL, patients were divided into two groups: group A (-9° < post-operative PI-LL<9°) and group B (post-operative PI-LL < -9°or post-operative PI-LL>9°). Independent t test and χ(2) test were performed for statistical analysis. For all statistical analysis, the level of significance was set at P < 0.05.</p><p><b>RESULTS</b>No difference was observed in terms of loss of correction between two groups during follow-up. More implant failure were observed in group B (15.63% vs. 6.7%, χ(2) = 21.85, P = 0.012). In addition, patients with better PI-LL matching came with better visual analogue scale (3.9 ± 2.4 vs. 5.2 ± 3.3, F = 0.089, P = 0.024).</p><p><b>CONCLUSION</b>Worse quality of life and increased risk for implant failure during follow-up may be related to mismatched PI-LL.</p>

Abnormal growth of spine in patients with adolescent idiopathic thoracic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate if the growth patterns of the spine and pelvis are consistent in adolescent idiopathic scoliosis (AIS) patients with single thoracic curves.</p><p><b>METHODS</b>Forty-eight thoracic adolescent idiopathic scoliosis (T-AIS) female patients and 48 healthy age-matched adolescents were recruited consecutively between December 2011 and October 2012. Radiographic parameters including height of spine (HOS), length of spine (LOS), height of thoracic spine (HOT), length of thoracic spine (LOT), height of pelvis (HOP), width of pelvis (WOP) and width of thorax (WOT) were measured on the long-cassette posteroanterior standing radiographs. In addition, ratios including HOS/HOP, LOS/HOP, HOT/HOP, LOT/HOP, LOS/LOT, WOT/WOP were also calculated. Independent t-test was performed to compare the radiographic parameters and ratios between the two groups.</p><p><b>RESULTS</b>Compared to the age-matched healthy adolescents, T-AIS patients had a significantly higher LOS and LOT (t = -2.364 and -1.495, P = 0.020 and 0.043) and smaller HOS and HOT (t = 2.060 and 3.359, P = 0.042 and 0.001). Yet, all of HOP, WOP and WOT showed no significant difference between T-AIS patients and healthy adolescents. Similarly, LOS/HOP and LOT/HOP were significantly higher in T-AIS patients as may be expected with an average LOS/HOP of 2.26 ± 0.14 in normal controls.In addition, LOS/LOT in normal controls had a trend of increase with age which was different from the stable LOS/LOT in T-AIS patients, indicating an increased growth of thoracic vertebra compared to lumbar vertebra.</p><p><b>CONCLUSIONS</b>Compared to the age-matched healthy adolescents, T-AIS patients have an abnormal growth characteristics with longer spine. The growth of pelvis and thorax show no significant differences between T-AIS patients and healthy adolescents.</p>

Effect of intervertebral disc degeneration on spinal flexibility in patients with degenerative lumbar scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate degenerative changes of the intervertebral disc and their impact on spinal flexibility in patients with degenerative lumbar scoliosis (DLS).</p><p><b>METHODS</b>Retrospective analysis of 66 patients (average age 58.4 years, 10 males and 56 females) with DLS was conducted from May 2008 to February 2014. For all patients, pre-operative standing X-ray film, Bending X-ray films and thoracolumbar MRI were taken. Cobb's angle was measured in each X-ray film and intervertebral angle was measured in both standing and Bending X-ray films. All discs were graded according to Pfirrmann degeneration grades on T2 weighted saggital MRI imaging. Statistical analyses were performed to determine the correlation between intervertebral disc degeneration with the whole spine flexibility and segmental flexibility.</p><p><b>RESULTS</b>For all 66 subjects, the average Cobb's angle of pre-operative and bending X-ray film was 36° ± 13°, 21° ± 11°, respectively. The average flexibility was 45% ± 15% in our study. Totally 268 discs were graded, including gradeI8, II 68, III 83, IV 91, V 18. In the main curve, there was significant correlation between the average degree of disc degeneration and the whole spine flexibility(r = -0.727, P < 0.01). There was significant correlation between the grade of segmental disc degeneration and segmental flexibility (P < 0.01) . The apical intervertebral disc had the most degeneration (P < 0.01) and worst flexibility (P < 0.01) , compared with other discs in the main curve.</p><p><b>CONCLUSIONS</b>The degree of intervertebral disc degeneration is closely correlated with spinal flexibility in DLS. The more the disc degeneration is, the worse the spinal flexibility becomes.</p>