Coronal shear fractures of the femoral neck (CSFF) are the most challenging to treat among proximal femur fractures, directly affecting the life expectancy of patients with osteoporosis. However, an adequate osteosynt...Coronal shear fractures of the femoral neck (CSFF) are the most challenging to treat among proximal femur fractures, directly affecting the life expectancy of patients with osteoporosis. However, an adequate osteosynthesis method has not been elucidated yet. This study investigated the displacement direction of the femoral head fragment and its effect on the bone using finite element method. A finite element model for CSFF was developed from CT image data of a patient with osteoporosis using Mechanical Finder (ver. 11). Subsequently, finite element analyses were performed on six osteosynthesis models under maximum load applied during walking. The compressive stresses, tensile stresses, and compressive strains of each model were examined. The results suggested that the compressive and tensile stress distributions were concentrated on the anterior side of the femoral neck. Compressive strain distribution in the femoral head and neck was concentrated in four areas: at the tip of the blade or lag screw, the anteroinferior side of the blade or lag screw near the fracture site, and the upper right and lower left near the junction of the blade or lag screw and nail. Thus, the distribution of both these stresses revealed that the femoral head fragment was prone to anterior and inferior displacement. Distribution of compressive strains revealed the direction of the stress exerted by the osteosynthetic implant on the bone. The same results were observed in all osteosynthetic implants;thus, the findings could lay the foundation for developing methods for placing osteosynthetic implants less prone to displacement and the osteosynthetic implants themselves. In particular, the study provides insight into the optimal treatment of CSFF.展开更多
BACKGROUND Coronal shear fractures of the distal humerus are rare injuries and are technically challenging to manage.Open reduction and internal fixation(ORIF)has become the preferred treatment because it provides ana...BACKGROUND Coronal shear fractures of the distal humerus are rare injuries and are technically challenging to manage.Open reduction and internal fixation(ORIF)has become the preferred treatment because it provides anatomical reduction,stable internal fixation,and early motion,but the optimal surgical approach remains controversial.CASE SUMMARY We report three cases of coronal shear fractures of the distal humerus treated successfully by ORIF via a novel surgical approach,in which lateral epicondyle osteotomy was performed based on the extended lateral approach.We named the novel surgical approach the lateral epicondyle osteotomy approach.All patients underwent surgical treatment and were discharged successfully.All patients had excellent functional results according to the Mayo elbow performance score.The average range of motion was 118°in flexion/extension and 172°in pronation/supination.Only case 2 had a complication,which was implant prolapse.CONCLUSION We demonstrated that the lateral epicondyle osteotomy approach in ORIF is effective and safe for coronal shear fractures of the distal humerus.展开更多
文摘Coronal shear fractures of the femoral neck (CSFF) are the most challenging to treat among proximal femur fractures, directly affecting the life expectancy of patients with osteoporosis. However, an adequate osteosynthesis method has not been elucidated yet. This study investigated the displacement direction of the femoral head fragment and its effect on the bone using finite element method. A finite element model for CSFF was developed from CT image data of a patient with osteoporosis using Mechanical Finder (ver. 11). Subsequently, finite element analyses were performed on six osteosynthesis models under maximum load applied during walking. The compressive stresses, tensile stresses, and compressive strains of each model were examined. The results suggested that the compressive and tensile stress distributions were concentrated on the anterior side of the femoral neck. Compressive strain distribution in the femoral head and neck was concentrated in four areas: at the tip of the blade or lag screw, the anteroinferior side of the blade or lag screw near the fracture site, and the upper right and lower left near the junction of the blade or lag screw and nail. Thus, the distribution of both these stresses revealed that the femoral head fragment was prone to anterior and inferior displacement. Distribution of compressive strains revealed the direction of the stress exerted by the osteosynthetic implant on the bone. The same results were observed in all osteosynthetic implants;thus, the findings could lay the foundation for developing methods for placing osteosynthetic implants less prone to displacement and the osteosynthetic implants themselves. In particular, the study provides insight into the optimal treatment of CSFF.
文摘BACKGROUND Coronal shear fractures of the distal humerus are rare injuries and are technically challenging to manage.Open reduction and internal fixation(ORIF)has become the preferred treatment because it provides anatomical reduction,stable internal fixation,and early motion,but the optimal surgical approach remains controversial.CASE SUMMARY We report three cases of coronal shear fractures of the distal humerus treated successfully by ORIF via a novel surgical approach,in which lateral epicondyle osteotomy was performed based on the extended lateral approach.We named the novel surgical approach the lateral epicondyle osteotomy approach.All patients underwent surgical treatment and were discharged successfully.All patients had excellent functional results according to the Mayo elbow performance score.The average range of motion was 118°in flexion/extension and 172°in pronation/supination.Only case 2 had a complication,which was implant prolapse.CONCLUSION We demonstrated that the lateral epicondyle osteotomy approach in ORIF is effective and safe for coronal shear fractures of the distal humerus.
