髋关节股骨头坏死重建之生物力学基础.ppt

中國 骨科年會 , 廣州，2004 年 七月,Hip AVN Reconstruction & Its Biomechanical Foundation,髖關節壞死重建 之生物力學基礎,Mayo,Johns Hopkins,AVN Demographics,Affects young population 300,000 - 600,000 people have AVN of the femoral head in the U.S. 20,000 THR/ yr due to AVN 15,000 20,000 new cases every year High bilaterality rate: 55% to 60%,ETIOLOGY (nontraumatic AVN),ETOH Steroids Hemoglobinopathies Gaucher Disease Intraosseous lipid deposition Hypersensitivity reactions Thromboplastin release (pregnancy, malignant tumors, inflammatory bowel Dz),Early AVN Treatment Options,Core decompression Free or vascular fibula graft Trap-door procedure Femoral osteotomy Bio-structural augmentation technique - A. Leali, J. Fetto BMP injection? Biophysical stimulation?,W. Petty, et al,Free Vascular Fibula Graft,J. Urbaniak,Bio-Structural Augmentation in Treatment of AVN,E. Chao, JHU,Concept Rationale Biomechanical justification,J. Fetto, A. Leali NYU,Bio-Structural Augmentation Technique,Osteoinductive material (BMPs),Osteogenic potential Stimulates new bone formation and maturation within 2-3 weeks (osteinduction) Accelerates bone healing process,Bio-Structural Augmentation Technique,AVN Support Bone Screw,Provides Structural Support Biologically compatible Helps create a stable construct underneath the vulnerable necrotic area.,Bio-Structural Augmentation in Treatment of AVN,Screw material? Screw location? Screw size? Screw number? Augmentation material?,Basic Questions,Prediction of head collapse,Subchondral bone collapse,Buckling Load,Virtual Interactive Musculoskeletal System,VIMS - Models VIMS - Tools VIMS - Labs,“VIMS - Net”,VIMS Models,Surface Models,Biomechanical Models,Solid/interface Models,Hybrid Models,Biomechanics of Articular Joint Function,Joint peak pressure is dependent on contact area Contact area is a function of joint loading and position,Head Coverage & Contact Stress During Activities of Daily Living,Dynamic hip pressure in ADL,Normal Gait,Standing Up,Contact Area & Pressure Distribution during Gait,50% stance,Posterior,Medial,Stress distribution in normal, AVN & reconstructive femoral head,normal,AVN,AVN witscrew,1,2,Bone collapse index:,Node 1 Node 2,Normal AVN Screw,0.82 0.68 0.93 0.73 0.85 0.61,AVN,Strength of cortical shell above the necrotic region decreases over 50%,Femoral head collapse,Summary,Bio-structural augmentation technique is effective VIMS is useful to predict collapse risk and optimize re- enforcement techniques,Orthopaedic Research Needs in Asia,1st AOAA-Asian Chapter Symposium May 6-8, 2004 Chiang-Mai/Thailand,Research Needs in Asia Objectives,Have an overview of the current orthopaedic research in Asia Get a list of relevant problems Learn about the needs Work out collaboration Coaching and mentoring,Is research relevant?, in Asia, where even simple fractures often lead to major morbidity due to inadequate treatment, all this (western research topics) is like having cake when there is no bread!,GT India,西方研究對臨床醫術有益嗎？,在亞洲， 由於處理不當往往最簡單的骨折都會