Health Sciences · Robert W. Jackson Arthroscopy
A white plastic element resembling the femoral component of a prototype version of a knee hemiarthroplasty. This plastic element is attached to a metal rod that terminates in a black plastic spherical element.
The shape of the white plastic element resembles the bearing surface bearing corresponds to the femoral condyle. Its inner (non-bearing) surface has a complex shape that is meant to fit into slots cut into the femoral condyle.
Accession Number: 2025.JAC.302
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Primary Materials: Plastic, Metal
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Dimensions (cm): Height = 4.5, Width = 1.6, Length = 14.
This artifact is likely a tool created to assist with the implantation of a developmental version of a knee hemiarthroplasty developed at the University of Toronto and Toronto General Hospital in the 1970s. Its purpose is likely to test the fit of the femoral implant into a groove cut into the femoral condyle, as well as to assist in placing bone cement onto the surface of the groove prior to the installation of the implant.
This artifact is in excellent cosmetic condition. It has no evident damage.
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Date of Manufacture: c. 1970s
This and other items related to the development of a partial knee replacement based on a MacIntosh plateau and a plastic femoral component were likely gathered by Dr. Robert W. Jackson during his time on staff at the Division of Orthopedic Surgery of Toronto General Hospital.
The Robert W. Jackson Arthroscopy Collection was acquired by the University of Toronto from Dr. Jackson’s family on November 12th, 2020.
Robert W. Jackson, Frederick P. Dewar, David L. MacIntosh, John P. Kostuik, and Robin Black. US4034418A: Artificial knee joint. US Patent. Awarded July 12, 1977.
The MacIntosh hemiarthroplasty (tibial plateau) was developed at the Toronto General Hospital (TGH) beginning in 1954. It is named for its inventor, orthopedic surgeon David L. MacIntosh (1914 – 2013). This was a platform that replaced the bearing surface of a tibial condyle. Though various materials were tried, after 1965 they were made exclusively of Vitallium alloy. A detailed history of that development can be found here.
At some point, possibly in the late 1960s, efforts began to create a femoral implant to match the tibial plateau in order to create a complete partial knee replacement. Little is known so far about this effort. However, the Jackson Collection contains several intriguing prototype artifacts. The best source is a 1977 patent (US patent 4,034,418), led by Robert W. Jackson and assigned to the University of Toronto, which describes a mature version of this arrangement.
This artifact was likely part of that developmental process. Its form represents an earlier version of the femoral implant than is depicted in the 1977 patent.