Wear and damage of articular cartilage with friction against orthopedic implant materials.
The objective of this study was to measure the wear response of immature bovine articular cartilage tested against glass or alloys used in hemiarthroplasties. Two cobalt chromium alloys and a stainless steel alloy were selected for these investigations. The surface roughness of one of the cobalt chromium alloys was also varied within the range considered acceptable by regulatory agencies. Cartilage disks were tested in a configuration that promoted loss of interstitial fluid pressurization to accelerate conditions believed to occur in hemiarthroplasties. Results showed that considerably more damage occurred in cartilage samples tested against stainless steel (10 nm roughness) and low carbon cobalt chromium alloy (27 nm roughness) compared to glass (10 nm) and smoother low or high carbon cobalt chromium (10 nm). The two materials producing the greatest damage also exhibited higher equilibrium friction coefficients. Cartilage damage occurred primarily in the form of delamination at the interface between the superficial tangential zone and the transitional middle zone, with much less evidence of abrasive wear at the articular surface. These results suggest that cartilage damage from frictional loading occurs as a result of subsurface fatigue failure leading to the delamination. Surface chemistry and surface roughness of implant materials can have a significant influence on tissue damage, even when using materials and roughness values that satisfy regulatory requirements.
Departments of Mechanical Engineering, Biomedical Engineering, and Orthopaedic Surgery, Columbia University, New York, NY, USA.
Sevan R
SR
Oungoulian
Departments of Mechanical Engineering, Biomedical Engineering, and Orthopaedic Surgery, Columbia University, New York, NY, USA.
Krista M
KM
Durney
Departments of Mechanical Engineering, Biomedical Engineering, and Orthopaedic Surgery, Columbia University, New York, NY, USA.
Brian K
BK
Jones
Departments of Mechanical Engineering, Biomedical Engineering, and Orthopaedic Surgery, Columbia University, New York, NY, USA.
Christopher S
CS
Ahmad
Departments of Mechanical Engineering, Biomedical Engineering, and Orthopaedic Surgery, Columbia University, New York, NY, USA.
Clark T
CT
Hung
Departments of Mechanical Engineering, Biomedical Engineering, and Orthopaedic Surgery, Columbia University, New York, NY, USA. Electronic address: ateshian@columbia.edu.
Gerard A
GA
Ateshian
D000497:Alloys; D000818:Animals; D002356:Cartilage; D002358:Cartilage, Articular / Q000502:physiology*; D002417:Cattle; D002858:Chromium Alloys / Q000737:chemistry; D005269:Femur / Q000601:surgery; D017276:Friction; D062785:Hemiarthroplasty / Q000295:instrumentation* / Q000379:methods; D008422:Materials Testing; D019736:Prostheses and Implants; D011475:Prosthesis Failure; D013193:Stainless Steel / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013977:Tibia / Q000601:surgery
D000497:Alloys; D002858:Chromium Alloys; D013193:Stainless Steel
Cartilage; Damage; Degeneration; Friction; Hemiarthroplasty; Orthopedic implants; Wear