10.3969/j.issn.2095-4344.2013.26.010

The design principle and application of an adjustable spine prone frame are introduced. Adjustable spine prone frame is used in posterior lumbar surgery, during operation, X-ray can shoot fast and internal fixation implants can fix accurately, the vacant abdominal ensure normal respiratory and circulatory function, and the lumbar curvature can adjust conveniently. It meets the surgical position and care requirements, can prevent the complications effectively.
Equipment Design ; Humans ; Lumbar Vertebrae ; surgery ; Orthopedic Procedures ; instrumentation ; Prone Position

BACKGROUND:Developmental dysplasia of the hip often leads to limb deformities in children,and the research related to its diagnosis and treatment has been gradually clarified.Recently,the finite element method has been paid attention to by scholars in the research related to developmental dysplasia of the hip because of its advantages. OBJECTIVE:Through literature search and review of the relevant research progress of finite element method in children's developmental dysplasia of the hip and treatment,analyze and summarize its advantages and disadvantages,and explore the direction of further research in the future. METHODS:PubMed,SCI,CBM,and CNKI were searched for relevant articles published from January 2014 to November 2023 with the key words of"developmental dysplasia(dislocation)of the hip,dysplasia of the hip,finite element analysis(method),pavlik harness,fixation in herringbone position,biomechanics,pelvic osteotomies,pemberton,salter,dega,periacetabular osteotomy,children"in Chinese and English.A small number of long-term articles were included,and 62 articles were finally included for analysis through screening. RESULTS AND CONCLUSION:(1)The mechanical environment of hip joint in children with developmental dysplasia of the hip was abnormal.The pressure in acetabulum was uneven.The stress increased and concentrated;the joint contact area decreased,and the local stress concentrated in femoral neck.(2)In the Pavlik sling and herringbone fixation,the mechanical environment of the hip was improved;the concentrated high stress area disappeared and the joint contact area increased,but the excessive abduction angle led to the increase of stress in the acetabulum and the lateral femoral head.(3)After pelvic osteotomy,the stress environment of hip joint and sacroiliac joint was improved.There was no single hinge in the three kinds of osteotomy,and the stress load position was different according to the age of the children.(4)After peri-acetabular osteotomy,the joint contact pressure was close to normal,but it was difficult to recover in patients with non-spherical femoral head.(5)The postoperative X-ray film findings could not show that the joint contact mechanics was the best.(6)It is indicated that the information that cannot be measured in the body can be obtained by using the finite element method,which can be operated in a virtual environment without the limitation of time and ethics.It can directly see the stress change area of normal and developmental dysplasia of the hip,explain the effectiveness of treatment from the point of view of mechanics,establish a specific finite element model and tailor-made operation plan for patients who need osteotomy.There is no standard or unified standard for the finite element modeling of developmental dysplasia of the hip and the material characteristic parameters of children's hip joint.Due to the inherent limitations of finite element method,it is impossible to analyze the model that contains bone,cartilage,ligament,muscle and other elements at the same time.The operation of finite element analysis is difficult,although it has advantages,it is not universal,and the current research sample size is small,which needs to be further expanded and verified.