Three-dimensiona navigation template assisted osteotomy for fracture malunion of lateral condyle of humerus in children / 中华实用儿科临床杂志

ABSTRACT

Objective:To investigate the efficacy and safety of three-dimensional navigation template assisted osteotomy for fracture malunion of lateral condyle of humerus in children.Methods:Eighteen children with ma-lunion of fracture of lateral condyle of humerus were treated in Southern Medical University Third Affiliated Hospital from August 2012 to December 2019 and analyzed retrospectively.Among them, 12 cases were treated with routine ope-ration according to CT reconstruction and empirical osteotomy during the operation, the location of deformity was analyzed.Six cases were treated with navigation template assisted osteotomy according to the CT data of bilateral elbow joints, a three-dimensional bone model was established, and the coronal and sagittal deformities of the distal humerus were evaluated by comparing the images of the distal humerus of the affected side with the distal humerus of the healthy side, so as to determine the best plane of osteotomy and the target position of reduction.The preoperative simulation was carried out on the computer, and the osteotomy navigation template and reduction navigation template were designed.The navigation template was printed out with a 3D printer.During the operation, the osteotomy was corrected with the assistance of navigation template, and the broken end of osteotomy was fixed with hollow screw and fixed with 80 degree flexion plaster.The X-ray films of the two groups were reexamined regularly after operation.The amount of intraoperative blood loss, operation time, incidence of postoperative complications (necrosis of humeral head and trochlea, delayed ulnar nerve paralysis, and bone nonunion) and the recovery of flexion and the extension function of elbow joint were observed in the 2 groups.Results:The elbow joint activity of all children basically returned to normal, the orthopedic site of osteotomy achieved bony healing, and the orthopedic effects were satisfactory.All the 18 cases were followed up for 6-24 months (mean 15 months). According to the postoperative Dhillon score, the navigation template group was excellent in 1 case and better in 5 cases, while in the routine group, 11 cases were batter and 1 case was fair.There were no significant differences in Dhillon score between the 2 groups after operation ( P>0.05). There were no significant differences in the range of the motion of elbow joint between the 2 groups ( P>0.05). In the comparison of operation time and intraoperative blood loss, the navigation template group [(200.0±24.2) min, (85.0±10.9) mL]was better than the routine group[(232.0±20.1) min, (139.1±18.3) mL](all P<0.001). Conclusions:The application of three-dimensional humerus reconstruction and mirror image contrast to evaluate the distal humerus deformity of the affected side, and the design of osteotomy and reduction navigation template auxiliary operation can restore the normal anatomical structure of elbow joint to the greatest extent.Accurate correction, and the function of elbow joint recover well after operation, which optimizes the operation procedure, improves the safety and effectiveness of the operation.