Objective To investigate the changes of low back pain (LBP) and spinal sagittal parameters in patients with unilateral Crowe type Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA). Methods The clinical data of 30 patients who met the selection criteria between October 2018 and March 2020 were retrospectively analyzed. Patients were divided into LBP group (16 cases) and control group (14 cases) according to whether there was LBP before operation. There was no significant difference between the two groups of patients in gender, age, body mass index, affected sides, preoperative Harris score (P>0.05). Full-length lateral X-ray films of the spine were taken within 1 week before operation and at 1 year after operation, and the following imaging indicators were measured: sacral slope (SS), lumbar lordosis (LL ), spinal tilt (ST), spine-sacral angle (SSA), sagittal vertebral axis (SVA). The visual analogue scale (VAS) score, lumbar Oswestry disability index (ODI), the Harris score of the hip joint before operation and at 1 year after operation, and the occurrence of postoperative complications were collected and analysed. Results In the LBP group, LBP was relieved to varying degrees at 1 year after operation, of which 13 patients (81.3%) had complete LBP remission; VAS score decreased from 4.9±2.3 preoperatively to 0.3±0.8, ODI decreased from 33.5±22.6 preoperatively to 1.3±2.9, the differences were all significant (t=7.372, P=0.000; t=5.499, P=0.000). There was no new chronic LBP in the control group during follow-up. The Harris scores of the two groups significantly improved when compared with those before operation (P<0.05); there was no significant difference between the two groups at 1 year after operation (t=0.421, P=0.677). There was no significant difference in imaging indexes between the two groups before operation and the difference between pre- and post-operation (P>0.05). At 1 year after operation, ST and SVA in the LBP group, SSA in the control group, and SS in the two groups significantly improved when compared with those before operation (P<0.05); there was no significant difference in the other indexes between the two groups before and after operation (P>0.05). Conclusion Unilateral Crowe type Ⅳ DDH patients with LBP before operation were all relieved of LBP after THA. The relief of LBP may be related to the improvement of spinal balance, but not to lumbar lordosis and its changes.
Objective To investigate the radiological features of degenerative cervical kyphosis (DCK) and the relationship between cervical sagittal parameters. Methods The quality of life scores and imaging data of 89 patients with DCK treated between February 2019 and February 2022 were retrospectively analysed. There were 47 males and 42 females, with an average age of 48.4 years (range, 25-81 years). Quality of life scores included visual analogue scale (VAS) score and neck disability index (NDI). The imaging data included C0-C2 angle, C2-C7 angle, C3-C7 inclination of zygapophyseal joints, C7 slope (C7S), cervical sagittal vertical axis (cSVA), kyphosis range, and kyphosis focal. The patients were grouped by gender, and the differences of the above parameters between the two groups were compared. Pearson correlation was used to analyze the relationship between age, quality of life scores, and cervical sagittal parameters, and the relationship between cervical sagittal parameters. Results The preoperative VAS score was 0-9 (mean, 4.3); NDI was 16%-44% (mean, 30.0%). There was no significant difference in VAS score and NDI between male and female groups (P>0.05). The kyphosis range of cervical spines was C3-5 in 3 cases, C3-6 in 41 cases, C3-7 in 30 cases, C4-6 in 4 cases, C4-7 in 10 cases, C5-7 in 1 case, and the kyphosis focal was mostly located between C4-C5 (78/89, 87.64%). The C3-C7 inclination of zygapophyseal joints were (60.25±5.56)°, (55.42±5.77)°, (53.03±6.33)°, (58.39±7.27)°, and (64.70±6.40)°, respectively. The C0-C2 angle, C2-C7 angle, C7S, and cSVA were (–23.81±6.74)°, (10.15±2.94)°, (15.31±4.59)°, and (2.37±1.19) mm, respectively. The C7S and cSVA of males were significantly larger than females (P<0.05), with no significant difference in other parameters between male and female groups (P>0.05). VAS score and NDI were negatively correlated with C0-C2 angle (P<0.05), and positively correlated with C2-C7 angle and cSVA (P<0.05); VAS score was negatively correlated with C7S (P<0.05). Except VAS, NDI and all cervical sagittal parameters were affected by age. Age was positively correlated with NDI, C7S, and cSVA (P<0.05), and negatively correlated with C0-C2 angle and C2-C7 angle (P<0.05). The correlation analysis of cervical sagittal parameters showed that C0-C2 angle was negatively correlated with C2-C7 angle and cSVA (P<0.05); C7S was negatively correlated with C2-C7 angle (P<0.05) and positively correlated with cSVA (P<0.05). There was no correlation among other parameters (P>0.05). ConclusionThe inclination of zygapophyseal joints of cervical spines of DCK patients is U-shaped in the kyphosis range, and the inclination at the kyphosis focal is the smallest. When cervical degenerative kyphosis occurs, in addition to the interaction of sagittal parameters, age, gender, neck pain, and dysfunction will also affect the cervical sagittal balance. Furthermore, cervical curvature and morphological changes are not purely local problems.