Massachusetts Institute of Technology VE RII! TAS Harvard medical school Brigham and Womens/Massachusetts General Hosp VA Boston Healthcare System 279J/396J/BE441HST522J BIOMATERIALS FOR JOINT REPLACEMENT M. Spector, Ph. D, and I.v.Yannas, Ph.D httpstellarmit.edu/s/course/2/Fa02/2.79
Massachusetts In Massachusetts Institute of Technology stitute of Technology Harvard Medical School Harvard Medical School Brigham and Wo Brigham and Women’s/Massachusetts General Hosp. men’s/Massachusetts General Hosp. VA Boston Healthcare System VA Boston Healthcare System 2.79J/3.96J/BE.441/HST522J 2.79J/3.96J/BE.441/HST522J BIOMATERIALS FOR JOINT BIOMATERIALS FOR JOINT REPLACEMENT REPLACEMENT M. Spector, Ph.D. and I.V. Yannas, Ph.D. M. Spector, Ph.D. and I.V. Yannas, Ph.D. http://stellar.mit.edu/S/course/2/fa02/2.79j http://stellar.mit.edu/S/course/2/fa02/2.79j
TISSUES COMPRISING JOINTS Permanent Regeneration Prosthesis Scaffold Bone Yes Yes Articular cartilage 0 Yes* Meniscus 0 Yes x Ligaments No Yes i Synovium No No s In the process of being developed
TISSUES COMPRISING JOINTS TISSUES COMPRISING JOINTS Permanent Permanent Regeneration Regeneration Prosthesis Prosthesis Scaffold Scaffold Bone Yes Yes Articular cartilage Articular cartilage No Yes* Meniscus Meniscus No Yes* Ligaments Ligaments No Yes* Synovium Synovium No No * In the process of being developed * In the process of being developed
JOINT REPLACEMENT PROSTHESES Fit Anatomy Function Kinematics; Range of Motion Fixation Bone cement, bone interdigitation with an irregular surface, bone ingrowth into a porous coating Tribology Friction. Wear and Lubrication Other effects Stress shielding
JOINT REPLACEMENT PROSTHESES JOINT REPLACEMENT PROSTHESES • Fit – Anatomy Anatomy • Function Function – Kinematics; Range of Motion Kinematics; Range of Motion • Fixation Fixation – Bone cement, bone Bone cement, bone interdigitation interdigitation with an irregular with an irregular surface, bone surface, bone ingrowth ingrowth into a porous coating into a porous coating • Tribology Tribology – Friction, Wear, and L Friction, Wear, and L ubrication brication • Other Effects Other Effects – Stress Shielding Stress Shielding
Bone cement Images removed due to Self-Curing polymethylmethacrylate copyright considerations Porous Coatings for Bone Ingrowth Images removed due to copyright considerations Porous Coated Tibial Component Images removed due to copyright considerations
Bone Cement Self-Curing Polymethylmethacrylate Images removed due to copyright considerations. Images removed due to Porous Coatings for Bone Ingrowth copyright considerations. Images removed due to Porous Coated Tibial Component copyright considerations
JOINT REPLACEMENT PROSTHESES Fit Anatomy · Function Kinematics; Range of motion Fixation Tribology Friction Wear and Lubrication Cell response to particulate wear debris Other effects Stress Shielding
JOINT REPLACEMENT PROSTHESES JOINT REPLACEMENT PROSTHESES • Fit – Anatomy Anatomy • Function Function – Kinematics; Range of Motion Kinematics; Range of Motion • Fixation Fixation • Tribology Tribology – Friction, Wear, and L Friction, Wear, and L ubrication brication – Cell response to particulate wear debris Cell response to particulate wear debris • Other Effects Other Effects – Stress Shielding Stress Shielding
PROGRESSION OF OSTEOLYSIS HYLAMER”CUP Image removed due to copyright considerations
PROGRESSION OF OSTEOLYSIS: “HYLAMER” CUP Image removed due to copyright considerations. Image removed due to copyright considerations
Why artificial Joints Fail Image removed due to copyright considerations Spice, Byron "Particle Disease Seen As Plague on Total Joint Replacement Pittsburgh Post-Gazette
Why Artificial Joints Fail Image removed due to copyright considerations Image removed due to copyright considerations Spice, Byron. “Particle Disease Seen As Plague on Total Joint Replacement” Pittsburgh Post-Gazette
J Charnley, 1979 Photo removed due to copyright considerations
J. Charnley, 1979 Photo removed due to copyright considerations Photo removed due to copyright considerations
MACROPHAGE RESPONSE TO PARTICLES PROSTHESIS WEAR Osteoblasts Particles Bone resorption (Osteolysis BONE Enzymes PgE IL-1 Macrophage Chemoattractants Osteoclast (15-25μm) Osteoclast precursor cells
PROSTHESIS WEAR PROSTHESIS WEAR Particles Particles Bone Resorption Bone Resorption (Osteolysis) (Osteolysis) Macrophage Macrophage (15 -25 µm) IL - 1 PGE 2 Enzymes Enzymes Chemoattractants Chemoattractants MACROPHAGE RESPONSE MACROPHAGE RESPONSE TO PARTICLES TO PARTICLES BONE Osteoclast Osteoclast precursor cells precursor cells Osteoclast Osteoclast Osteoblasts Osteoblasts
POLYETHYLENE WEAR PARTICLES H McKellop, 1994 Hip Society The number of particles generated by a hip prosthesis 7x 10 particles/yr 700,000 particles/step
POLYETHYLENE WEAR POLYETHYLENE WEAR PARTICLES PARTICLES H. McKellop McKellop, 1994 Hip Society , 1994 Hip Society The number of particles generated by a hip The number of particles generated by a hip prosthesis prosthesis 7 x 1011 particles/yr. particles/yr. 700,000 particles/step 700,000 particles/step
