Objective To compare the difference in the inclination and anteversion angles of the acetabular cup measured by intraoperative robot-assisted total hip arthroplasty (THA) and postoperative X-ray films and CT imaging. MethodsThe clinical data of 54 patients (54 hips) who underwent robot-assisted THA between May 2020 and December 2020 were retrospectively analyzed. Among them, there were 26 males (26 hips) and 28 females (28 hips), with an average age of 58.4 years (range, 39-71 years). The body mass index was 19.2-29.3 kg/m2, with an average of 25.2 kg/m2. All the patients had their first THA, including 31 cases of osteonecrosis of the femoral head, 12 cases of hip arthritis, 8 cases of femoral neck fracture, and 3 cases of developmental dysplasia of the hip. The anteversion and inclination angles of the acetabular cup were obtained through the surgical data in the robot host system. All patients underwent X-ray and CT scan examination within 2-7 days after operation to obtain the postoperative anteversion and inclination angles of the acetabular cup. According to the concept of “Lewinnek safe zone”, the proportion of acetabular in the safe zone intra- and post-operation were compared. ResultsThe operation time was 57.8-89.2 minutes, with an average of 68.3 minutes; the intraoperative blood loss was 125.0-450.0 mL, with an average of 204.8 mL. No adverse events such as dislocation of hip joint and infection occurred during hospitalization. The anteversion angle of acetabular cup was (40.8±0.6)° during operation and (41.2±2.8)° after operation, with no significant difference (t=1.026, P=0.307). The anteversion angle of acetabular cup measured during operation was (17.6±1.4)°, which was significantly smaller than that measured after operation (23.4±3.8)°(t=10.520, P=0.000). According to “Lewinnek safe zone”, 54 hips (100%) were in the safety zone during operation, and 16 hips were out of the safety zone, 38 hips were in the safty zone after operation, the ratio of the hips in the safty zone was 70.4%, showing a significant difference (χ2=18.783, P=0.000). ConclusionRobot-assisted THA can obtain accurate placement of the acetabular cup, but there is a large deviation between the anteversion angle of the acetabular cup in the lateral position during operation and the supine position after operation. Further study is needed to define the intraoperative placement position of the acetabular cup.
Objective To evaluate the three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip (DDH) using a semi-automated measurement software, which provides data for the differential diagnosis, surgical planning, surgical instrument design, and postoperative evaluation of hip related diseases. MethodsEighty-four cases of CT data in asymptomatic population (asymptomatic group) and 47 cases of CT data in DDH patients (DDH group) were collected. There was no significant difference in gender and age (including age of male and female subgroups) between the two groups (P<0.05). MaxTHA, a semi-automatic measurement software, was used to measure acetabular inclination and anteversion, including operative inclination (OI), radiographic inclination (RI), anatomic inclination (AI), operative anteversion (OA), radiographic anteversion (RA), and anatomic anteversion (AA). Comparisons were made between the two populations, between different Crowe classification subgroups, between different gender subgroups, and between left and right sides of acetabula. Results The comparison between asymptomatic group, healthy side of DDH group, and affected side of DDH group showed that there was no significant difference in acetabular orientation between asymptomatic group and healthy side of DDH group (P>0.05). The OI, RI, and AI of affected side of DDH group were significantly higher than those in healthy side of DDH group and asymptomatic group, and AA was significantly lower than that in healthy side of DDH group and asymptomatic group (P<0.05). The comparison between the normal acetabula and DDH acetabula with different Crowe classifications showed that there was no significant difference in the acetabulum orientation between Crowe Ⅰ group and the normal group (P>0.05). The OI, RI, and AI of Crowe Ⅱ, Ⅲ, and Ⅳ groups were significantly higher than those of normal group (P<0.05), the OI of Crowe Ⅲ group, RI and AI of Crowe Ⅳ group were significantly higher than those of Crowe Ⅰ group (P<0.05), the AI of Crowe Ⅳ group was significantly higher than that of Crowe Ⅱ group (P<0.05), and the OA, RA, and AA of Crowe Ⅲ group were significantly lower than other subgroups (P<0.05) except Crowe Ⅰ group. The OA, RA, and AA in asymptomatic female group, and the OA and AI in DDH female group were significantly higher than those in all male groups (P<0.05). The OI, RI, AI, and OA of the right acetabula in asymptomatic male group, and the RI and AI of the right acetabula in asymptomatic female group were significantly higher than those on the left side (P<0.05). ConclusionThere were significant differences in acetabular orientation between asymptomatic and DDH populations, inter-group differences among Crowe classification subgroups, inter-gender differences among subgroups, and bilateral differences among asymptomatic individuals.
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.
Objective To investigate the accuracy and effectiveness of acetabular cup placement in total hip arthroplasty (THA) after lumbar fusion applying of modified acetabular anteversion and inclination angles test system. Methods A clinical data of 45 patients undergoing THA for osteoarthritis between January 2018 and June 2023 was retrospectively analyzed. All patients had previously received lumbar fusion. The modified acetabular anteversion and inclination angle test system was used in 26 cases (observation group) and not used in 19 cases (control group) during THA. There was no significant difference in baseline data such as gender, age, body mass index, operative side, number of lumbar fusion segments, and preoperative Harris score between the two groups (P>0.05). The position of acetabular prosthesis, hip function (Harris score), and incidence of complications were compared between the two groups.Results In the observation group, all acetabular cups were in the safe zone (anteversion angle, 25°-30°) during operation, and 1 acetabular cup (3.85%) was not in the safe zone after operation. In the control group, 9 acetabular cups (47.37%) were not in the safe zone. The postoperative difference between the two groups was significant (P<0.05). There was no significant difference between intra- and post-operative acetabular inclination angles in the observation group (P>0.05), and the postoperative acetabular inclination angle was significantly smaller in the observation group than in the control group (P<0.05). All incisions healed by first intention and no infection occurred. All patients were followed up 6 months. There was no significant difference in Harris score between the two groups at different time point (P>0.05), and there were significant differences between different time points in the two groups (P<0.05). No joint dislocation occurred in the observation group during follow-up, while dislocation occurred in 2 cases and femoral impingement syndrome occurred in 1 case of the control group. There was no significant difference in the incidence of complications between the two groups (P>0.05). Conclusion For THA patients with lumbar fusion, the ideal placement angle of the acetabular cup can be obtained by using the modified acetabular anteversion and inclination angles test system during operation.