ObjectiveTo explore the effect on sagittal spine-pelvis balance of different fusion segments in anterior cervical discectomy and fusion (ACDF).MethodsThe clinical data of 326 patients with cervical spondylotic myelopathy, treated by ACDF between January 2010 and December 2016, was retrospectively analysed. There were 175 males and 151 females with an average age of 56 years (range, 34-81 years). Fusion segments included single segment in 69 cases, double segments in 85 cases, three segments in 90 cases, and four segments in 82 cases. Full spine anterolateral X-ray films were performed before operationand at 12 months after operation. The spine-pelvis parameters of fusion segments were measured and compared. The parameters included C0-2 Cobb angle, C2-7 Cobb angle, C2-7 sagittal vertical axis (C2-7 SVA), T1 slope (T1S), thoracic inlet angle (TIA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), C7 sagittal vertical axis (C7 SVA), T1 pelvic angle (TPA). The Japanese Orthopaedic Association (JOA) score of cervical spine and visual analogue scale (VAS) scores of pain of cervical spine and upper extremity were compared before operation and at 12 months after operation. Pearson correlation analysis was performed on LL, PI, SS, C7 SVA, and TPA before and after operation to evaluate the changes of spine-pelvis fitting relationship after ACDF.ResultsAll 326 patients were followed up 12-32 months (mean, 18.5 months). During the follow-up period, internal fixator was in place, and no spinal cord nerve or peripheral soft tissue injury was found. JOA scores and cervical VAS scores improved significantly at 12 months after operation (P<0.05), no significant difference was found in VAS scores of upper extremity when compared with preoperative scores (P>0.05). The preoperative cervical VAS scores and the postoperative JOA scores at 12 months had significant differences between groups (P<0.05). At 12 months after operation, there was no significant difference in sagittal spine-pelvis parameters in the single segment group compared with preoperative ones (P>0.05); but the C0-2 Cobb angle, C2-7 Cobb angle, C2-7 SVA, T1S, TIA, C7 SVA, and TPA in the double segments, three segments, and four segments groups were significant larger than preoperative ones (P<0.05). The C0-2 Cobb angle, C2-7 Cobb angle, T1S, C7 SVA, and TPA among 4 groups had significant differences before operation and at 12 months after operation (P<0.05). At 12 months after operation, the changes of C7 SVA and TPA in the double segments, three segments, and four segments groups were significantly larger than those in the single segment group (P<0.05). PI had positive correlations with LL and SS before and after operation in 4 groups (P<0.05).ConclusionNormal fitting relationship between lumbar spine and pelvis in physiological state also exists in patients with cervical spondylotic myelopathy, and ACDF can not change this specific relationship. In patients with cervical spondylotic myelopathy, the sagittal spine-pelvis sequence do not change after ACDF single-level fusion, while the sagittal spine-pelvis balance change after double-level and multi-level fusion.
ObjectiveTo explore the effect of percutaneous kyphoplasty (PKP) on lumbar-pelvic correlation in osteoporotic vertebral compressive fracture (OVCF).MethodsAccording to the inclusion criteria, 63 patients with primary osteoporosis between January 2012 and June 2017 were selected as the control group and 67 patients with single-segment lumbar OVCF receiving PKP and complete clinical data were included as the observation group. There was no significant difference in gender, age, and lumbar spine bone density between the two groups (P>0.05). The visual analogue scale (VAS) score and Oswestry Disability Index (ODI) score were used to assess lumbar pain and function before operation and at 3 days after operation in the observation group; lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS) were measured in lumbar lateral X-ray films which were taken before PKP and at 1 month after PKP. The same parameters were measured in the lumbar lateral X-ray films which were taken at the time of initial diagnosis in the control group.ResultsAll patients were followed up 3-24 months with an average of 5.8 months in the observation group. The VAS score decreased from 5.6±1.8 before PKP to 2.8±1.3 at 3 days after PKP (t=14.082, P=0.000); ODI decreased from 50.1%±5.0% before PKP to 18.2%±1.8% (t=47.011, P=0.000). Compared with the control group, the LL, PI, and SS decreased and the PT increased in the observation group, and only the difference in LL between the two groups was significant (P<0.05). In the observation group, the LL and SS significantly increased (P<0.05) and PT significantly decreased (P<0.05) at 1 month after operation when compared with preoperative ones, and PI decreased, but the difference was not significant (P>0.05). In the control group, LL was positively correlated with PI and SS (P<0.05); PI was positively correlated with PT and SS (P<0.05). In the observation group, PI was positively correlated with SS (P<0.05) before and after PKP.ConclusionOVCF patients lost the specific lumbar-pelvic correlation. PKP can restore lumbar lordosis, but it still can not restore the normal physiological fitting.