Correlation analysis between postoperative hip pain and spino-pelvic-hip parameters in adult scoliosis patients after long-segment spinal fusion

English Keywords:Scoliosis  Hip joint  Spine-pelvic parameters  Acetabular coverage  Adult

English Abstract:

  【Abstract】 Objectives: To explore the correlations between postoperative hip pain and spino-pelvic-hip parameters in adult scoliosis patients after long-segment spinal fusion. Methods: This study was a retrospective analysis of a cohort of 76 adult scoliosis patients who underwent long-segment spinal fusions at Peking University Third Hospital between December 2009 and August 2015. The inclusion criteria included: (1) at least four segments involved, with the lower end of fixation at sacrum or ilium; (2) no preoperative hip pain or acetabular dysplasia; (3) complete clinical data; and (4) at least two years of follow-up. The patients were divided into pain group(PG) and control group(CG) based on whether hip pain was reported at the end of follow-up. There were 34 cases in PG and 42 in CG. There were no significant differences in age, gender, number of fusion segments, body mass index(BMI) and the use of sacral-2 alar iliac(S2AI) screw between the two groups(P＞0.05）. Visual analog scale(VAS) was usd to assess the postoperative hip pain in PG patients. Two sets of parameters were measured and recorded for all patients before and after the fusion surgery. The first set was based on anterior pelvic radiograph and consisted of acetabular coverage, tonnis angle, central-edge angle（CE angle）; the second set was measured on both anterior and lateral full-spine radiographs, including lumber lordosis(LL), sacrum slop(SS), pelvic incidence(PI), Cobb angle, coronal vertical axis(CVA) and sagittal vertical axis(SVA). t-test, variance analysis, and Pearson correlation analysis were used to compare the parameters between groups and analysis correlations of acetabular coverage, tonnis angle, CE angle variables and LL, SS and PI variables in PG. Results: The average VAS score of PG patients was 3.9±1.4(range: 2-7). There were statistically significant differences in the alterations of acetabular coverage and CE angle between the two groups(P<0.05), but none in those of tonnis angle, LL, SS, PI, CVA, SVA and Cobb angle. The alteration of acetabular coverage before and after operation in PG was significantly correlated with that of LL(P<0.05), while CE angle and tonnis angle were not significantly correlated with spinal-pelvic parameters(P>0.05). Conclusions: There is significant correlation between hip pain and acetabular coverage, CE angle after long-segment spinal fusion of adult scoliosis patients, and acetabulum coverage changes are correlated with changes in LL in the PG.