Material Challenges for Biomedical Applications: An Example Peter Ping Liu, Ph D, PE, CQE, OCP and CSIT Professor and Coordinator of Graduate Programs School of Technology Eastern Illinois University Charleston, IL 61920 USA

An Example: Human Knee

Normal Knee With Healthy Articular Cartilage

Diseased Knee worn cartilage

Common Problems (Arthritis) Osteoarthritis (OA) Rheumatoid Arthritis (RA) Post-traumatic Arthritis

Pain Stiff joint Immobility Consequences Pain Stiff joint Immobility

Total joint replacement normally is the last treatment option if everything else fails.

Typical Total Knee Replacement

Total Hip Joint Replacement

Shoulder Replacement

Elbow Replacement

Challenges: Possible Complications of Surgery Problems with anesthesia Cardiovascular problems including heart attack Vascular problems including thrombus Bronchopulmonary problems including emboli Genitourinary problems Gastrointestinal problems.

Challenges: Joint Replacement Surgery Bleeding problems Blood clots in the legs and/or lungs Wound healing problems Damage to nerves and blood vessels Limb length discrepancy Bone erosion or abnormal bone formation Dislocation Infection Pain Bone fracture or non-union Component loosening

Challenges: Patients Physical therapy Moderate exercise Care of the joints

Materials Challenges: Mechanical Properties Support the load. No significant facture or fatigue.

Materials Challenges: Tribological Properties Low friction Minimum wear Small particle generation.

Materials Challenges: Chemical Properties Chemically inert in the body Compatible with tissue No adversary reaction/interaction

Typical Product Development (Laboratory) Biomechanical analysis Mechanical design and testing Environmental study: Saline, bovine serum and others

Typical Product Development Animal trial FDA compliance and approval Clinical trial Good manufacturing practice (quality assurance)