The Ultimate Strength and Failure Mechanism of Anthropoid Knee Joints,
Abstract
Testing of the anthropoid knee in three point loading indicates a progressive failure mechanism in an anterior loading situation. This phenomenon is investigated and is shown to be due to the failure of the connective tissue of the knee region as loading progresses. The first response is the patella settling into the intercondyle space of the tibia and contacting the tuberosity. This contact causes the posterior surface of the patella to be bruised. The second response is that of the posterior cruciate ligament failing at its point of insertion into the medial condyle. The ultimate and final failure of the joint occurs when the posterior cruciate ligament completely ruptures and causes the ligament of Wrisberg to tear its lateral condyle insertion allowing the complete collapse of the joint. The relationships between the angular displacement of the knee joint and the applied bending moment are shown for different size joints. The failure conditions are related also the joint sizes. The effects of freezing on the angular modulus of the joint and on its ultimate strength is shown to reduce the strength and modulus about 50%. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1971
- Accession Number
- AD0740452
Entities
People
- Carl H. Jacobs
- John O. Outwater
- Robert W. Castle
Organizations
- Air Force Research Laboratory