摘要
BACKGROUND:The traditional fixation method for femoral neck fractures is three hollow screws inverted triangle fixation,and the optimal fixation method for femoral neck fractures that have not achieved anatomical reduction is inconclusive. OBJECTIVE:To compare the biomechanical properties of cannulated screws internal fixation for sub-capitated femoral neck fracture with different reduction qualities based on finite element analysis. METHODS:The three-dimensional digital model was reconstructed using CT data of the proximal femur from a healthy male volunteer.The femur was modeled to sub-capitated femoral neck fractures.Fracture models were divided into anatomical reduction group,coxa vara group,and coxa valgus group.All fracture model groups were transferred using the standard group,screw depression group,and screw elevation group.A vertical downward stress of 1 400 N was applied to the femoral head at the top of the acetabulum.The displacement and stress distribution of the femur and internal fixator under different fixation methods were observed,and the maximum stress and displacement of the femur and fixator were compared. RESULTS AND CONCLUSION:(1)For anatomical reduction femoral neck fracture,the peak stress of fixation in the standard group,screw depression group and screw elevation group was 41.35,31.27 and 43.32 MPa,respectively.The maximum peak stress of the femur was found on the screw elevation group(28.58 MPa),and the standard group had the maximum peak displacement.(2)During hip varus,the stresses in the three subgroups were relatively dispersed and even.The peak stress of the femur in the standard group was the smallest,but the peak displacement was the largest.The stability of fixation might be poor.The peak displacement of the femur in the screw depression group was the smallest.(3)In the hip valgus,obvious screw stress concentration appeared in the screw depression group,and the peak displacement was the largest among the three subgroups,and an in-out-in phenomenon appeared.The peak stress of the screws in the screw elevation group was the largest among the three subgroups,but the peak displacement was the smallest.(4)It is concluded that for sub-capitated femoral neck fractures that are completely anatomically reduced,it is recommended to use standard inverted triangular nails for fixation.When the hip varus and hip valgus occur within the allowable range of the reduction standard,it is recommended to use the inverted triangle screw to fix it by rotating the corresponding angle in the same direction as the hip varus or valgus.
摘要
Objective To analyze the clinical efficacy and safety off emoral head replacement(FHR)assisting by the traction table in direct anterior approach(DAA)for the treatment of femur neck fractures in gerontal patients.Methods A retrospective analysis was conducted on 79 elderly patients who under went FHR for femoral neck fractures from March 2019 to July 2020.A total of 42 patients underwent FHR through DAA by using traction table were assigned to the observation group and 37 patients receiving FHR through the PLA to the control group.The perioperative data,follow-up results and complications were compared between the two groups.Results The observation group was significantly superior to the control group in intraoperative blood loss(P<0.05),where as the former was inferior to the latter in preoperative preparation time(P<0.05).There was no significant difference in anesthesia time and operation time between the two groups(P>0.05).The observation group resumed first postoperative standing time,partial-weight bearing walking time and full-weight bearing walk-ing time significantly earlier than control group(P<0.05).Harris score at 1 month after the operation in the observation group were significantly higher than that of the control group(P<0.05),whereas which became not statistical significant between the two groups in 6 months and 1 year(P>0.05).No significant difference was found between the two groups for the incidence of complications(P>0.05).Conclusion DAA-FHR assisting by the traction table for the treatment of femur neck fractures in the elderly was effective and safe,but the preoperative preparation time was longer.
摘要
Ocean is a unique and excellent resource that provides a diverse array of intriguing natural products. Marine natural products have demonstrated significant and extremely potent biological activities and have captured the attention of natural products chemists in the past few decades. It is increasingly recognized that a wealth of fascinating natural products and novel chemical entities will play a dominant role in the discovery of useful leads for the development of pharmaceutical agents and provide useful probes to lead to breakthroughs in a variety of life-science fields. This article focused on the research progress of chemistry of marine natural products in recent five years.