ABSTRACT
Objective:Comparison of four methods in intraoperative abduction angles (AA) measurements of human cast immobilization in developmental dysplasia of the hip (DDH) by visual inspection and electronic software according to different body surface markers.Methods:Data were retrospectively collected from January 2019 to November 2021 in a total of 27 patients (54 hips) who underwent closed or simple open reduction. There were 6 males and 21 females with an average age of 13.2 months. Five doctors used visual inspection and mobile phone software to measure the AA of the hip joint immediately during the operation, and compared with the postoperative MRI measurement results (AA-MRI). The four methods of intraoperative measurement were: Junior visualization (AA-JV), the intersection angle between the line connecting the center of the popliteal fossa and the contact center of the plaster frame and the line connecting the two ischial tuberosities; the same methods as method one by Senior visualization (AA-SV); the intersection angle between the line connecting the center of the popliteal fossa and the center of the anus and the line connecting the ischial tubercle (anus-popliteal, AA-AP); the intersection of the vertical line between the center of the popliteal fossa and the groin and the horizontal line of the center of the anus and the vertical line connecting the two ischial tuberosities intersect (anus-groin crease-popliteal, AA-AGCP). The t-test, correlation coefficient, linear regression and Bland-Altman test were used to evaluate the measurements. Results:Comparing the four intraoperative and postoperative AA-MRI measurement methods, AA-JV (42.69°±4.13°) < AA-SV (44.80°±4.08°) < AA-AGCP (46.25°±5.15°) < AA-MRI (47.68°±4.21°) < AA-AP (51.77°±5.30°), and the difference between AA-JV and AA-SV, AA-AP and AA-AGCP was statistically significant ( t=2.53, P=0.013; t=5.47, P=0.001), there was no significant difference between AA-AGCP and AA-MRI ( t=1.57, P=0.118). The inter-group agreement of the five methods ICC test ranged from 0.807 to 0.892, and the intra-group average agreement of AA-MRI was 0.948. All ICC results were greater than 0.75 with good agreement. Linear regression results showed that the four intraoperative measurement methods had a good or moderate linear relationship with AA-MRI, AA-AGCP ( R 2=0.499)>AA-AP ( R 2=0.318)>AA-SV ( R 2=0.253)>AA-JV ( R 2=0.217), AA-AGCP was the best measurement method. The results of Bland-Altman scatterplot of AA-AGCP and AA-MRI were in good agreement, the mean and standard deviation of bias were -0.796±3.247, and the limit of agreement was 95% LoA (-7.16, -5.57). Conclusion:The AA method of visualization before Spica casting was smaller than truth. The method AA-AGCP objectively by landmarks was the advocated means measuring abduction angle during operation with highly consistency, agreement and easily performed.
ABSTRACT
Objective To evaluate the femoral neck anteversion (FNA) of patients with unilateral developmental dysplasia of the hip (DDH) and reveal the developmental regularity of the proximal femur.Methods 366 three-dimensional CTs of unilateral DDH patients were categorized into three age groups:＜18 months, 18 months-3 years,and＞3 years.The femoral neck anteversion of both sides were measured and a statistical comparison was performed between them.The line chart showing the relationship of femoral neck anteversion and age was drawn to reveal the developmental regularity of the proximal femur.Results In total,the affected side of unilateral DDH had an femoral neck anteversion 1°～5° significantly larger than the unaffected side (P＜0.05).There was no statistical difference between affected and unaffeted sides in age group＜18 months and 18 months-3 years,while it was significant in age group＞3 years.Conclusion Pathological changes of the proximal femur were observed not only the affected side in unilateral DDH but also the unaffected side.The FNA symmetrically developed with age older.
ABSTRACT
Objective To define the normal reference values of acetabular index and Sharp angle through 2333 standard anterior-posterior pelvic radiographs. Methods In our study, 2333 normal anteriorposterior pelvic radiograph images with standard exposure were selected. All the images were diagnozed normal by two radiologists and two pediatricians according to the criteria of T(o)nnis. All subjects were without any neuromuscular diseases and congenital defoemity. The acetabular index was measure in the subjects between age 0 to 10 years, and the groups were divided monthly within 1 year and yearly between 1 to 10years. The Sharp angle was measure in the subjects after 10 years, and the groups were divided yearly in adolescence and decadely in adults. Normal values of each age groups and the correlation charts were completed according to statistical analysis. Results The mean acetabular index was 28.39° in neonates followed by a steep decrease in the first three months after born. It decreased to 22.17°in the 1st year, 12.80°in the 10th years and then kept constant. Acetabular index of the female was generally 1°-2°larger than that of the male with statistical significance. The mean Sharp angle was 46.72°in the 10th years, which decreased to 39.10°in the 18th years and 35.69°in elderly people. Another declination was observed after age 40.Generally no gender difference was observed. Conclusion Acetabular index and Sharp angle vary with age.They reflect a dramatic morphological change in the acetabulum before adulthood and stay constant afterwards. Gender difference is obvious in many age groups but not all. Normal reference ranges of both gender at all age groups should be considered in clinical evaluation.