Lecture 14u

Principle of Screw and Plate Fixation & Mechanical Behavior of Implant Materials

Roles of Implants ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Advantages of Internal Fixation ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Principles of Fixation ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Biomechanics of Dynamic Compression Plate (DCP) ,[object Object],[object Object],[object Object],[object Object],ttb.eng.wayne.edu / ~grimm/ME518/L19F3.html Beginning End Result

DCP (Cont’d) ,[object Object],[object Object],[object Object]

Plate Placement ,[object Object],[object Object],[object Object],[object Object],[object Object]

Plate and oblique fracture ,[object Object],[object Object],[object Object],A B

Dynamic Hip & Condular Screw Indications (DHS) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],http://tristan.membrane.com/aona/tech/ortho/dhs/dhs04.html

Sliding Compression Screw Devices ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Sliding Screw Plate Angle ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Sliding Screw Plate Angle ,[object Object],[object Object],[object Object],[object Object]

DHS Technique ,[object Object],[object Object],[object Object],[object Object],http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/laude_actu/laudepertroch_us.shtml

DHS Targeting Device ,[object Object],[object Object],[object Object],[object Object],http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/laude_actu/laudepertroch_us.shtml

DHS Guide Pin ,[object Object],[object Object],http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/laude_actu/laudepertroch_us.shtml

DHS Axial Screw ,[object Object],[object Object],[object Object],http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/laude_actu/laudepertroch_us.shtml

DHS Plate ,[object Object],[object Object],http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/laude_actu/laudepertroch_us.shtml

DHS Problems ,[object Object],[object Object],[object Object],[object Object]

Materials http:// www.me.udel.edu/~advani/research_interest/implants.htm http://www.orthopedictechreview.com/issues/sep00/case15.htm Composite Ceramic http://www.centerpulseorthopedics.com/us/patients/hip/hip_issues/index Metal: Rough & Polished http://www.centerpulseorthopedics.com/us/products/hip/allofit/index Polymer

Bio Materials ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Types of materials ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

http://www.engr.sjsu.edu/WofMatE/projects/srproject/srproj3.html#overview 190 GPa (used with cement) 200 GPa 110 GPa Young’s Modulus Excessively corrosive in some cases Susceptible to fatigue cracking Very high modulus PMMA cement may cause fracture or tissue reaction Co, Cr, Mo known to be toxic in ionic form; High modulus *varies with smooth or porous surface Poor wear characteristics *varies with smooth or porous surface Problems Rarely used in new designs in joint replacement; Fracture fixation devices Total joint arthroplasty (usually fixed with cement); Need to be inserted with a lower modulus polymer cement for fixation to prevent stress shielding of surrounding bone Cementless joint replacements (total knee arthroplasty); Fracture fixation devices Uses Strong, cheap, relatively biocompatible; annealed, cold worked or cold forged; relatively ductile-contouring of plates and wires Stronger and more corrosion resistant than stainless steel; Excellent resistance to fatigue, cracking, and stress Yield strength; Ti > Stainless Steel Benefits Cr, Ni, Mo Cr: oxide layer when dipped in Nitric acid (reduced corrosion) 30-60% Co 20-30% Cr 7-10% Mo Ti 6 Al 4 V Chemical Make-up Stainless Steel Cobalt-chromium-molybdenum Titanium Metals

Composites ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ceramics ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ceramics (cont’d) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Polyethylene ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Bone Cement ,[object Object],[object Object],[object Object]

Bone Cement ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],http:// www.totaljoints.info/bone_cement.htm

Bone Cement (cont’d) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Biodegradable materials ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Mechanical Properties of IM ,[object Object],[object Object],[object Object],[object Object],[object Object]

Elastic Modulus in increasing order of strength ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ultimate Tensile Strength in increasing order of strength ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Young’s Modulus ,[object Object],[object Object],http://www-materials.eng.cam.ac.uk/mpsite/interactive_charts/stiffness-cost/NS6Chart.html

Additional Resources ,[object Object]

Fracture Blisters ,[object Object],[object Object],[object Object],[object Object],[object Object],http:// www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd =Retrieve&db= PubMed&dopt = Abstract&list_uids =94046106

Varus Deformity at the knee ,[object Object],[object Object],[object Object],[object Object],http://www.wheelessonline.com/o12/74.htm http:// www.hyperdictionary.com /medical http://www.merckmedicus.com/pp/us/hcp/diseasemodules/osteoarthritis/diagnosis.jsp A B C

Oteotomy ,[object Object],[object Object],http://www.allaboutmydoc.com/surgeonweb/surgeonId.2729/clinicId.1432/theme.theme3/country.US/language.en/page.article/docId.31146

Proximal Femur (Hip) Fractures ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],http://www.orthoteers.co.uk/Nrujp~ij33lm/Orthhipfrac.htm

Lecture 14u

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (20)

Andere mochten auch

Andere mochten auch (14)

Ähnlich wie Lecture 14u

Ähnlich wie Lecture 14u (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Lecture 14u