Polycentric knee components

The Polycentric design was further modified by researchers at Mayo in 1973 to provide wider UHMWPE tracks [11]. Additional refinements of the Polycentric design, such as the introduction of UHMWPE ruimers with variable height, were proposed by Cracchiolo [12]. A review by Peterson et al. [13] in 1975 provides an instructive summary of the different types of Polycentric knee components, which were available from implant companies such as Howmedica and DePuy at the time. 

Gunston freely shared his drawings with Bryan and Peterson, and after some design modifications, the first Polycentric TKA was performed at the Mayo Clinic by July 1970. The first 81 Polycentric knees at the Mayo Clinic were fabricated by the hospital (Bryan and Peterson 1979). However, until 1978, the vast majority of the 1938 Polycentric components implanted at the Mayo Clinic were manufactured by orthopedic companies, such as Howmedica (Rutherford, NJ). 

Although the two components of Geometric knee were somewhat easier to implant than the four components of the Polycentric knee, long-term fixation... 

Surgeons at the Mayo Clinic started using Polycentric UKAs beginning in 1971 (Skolnick, Bryan, and Peterson 1975). This procedure used identical implant components as the TKR version of the Polycentric. Stolnick and colleagues (1975) described the 1-year results for 14 knees in 13 patients in 1975. By 1979, Bryan and Peterson (1979) had reported that 338 Polycentric UKAs had been performed at the Mayo Clinic. 

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