Abstract
From a regulatory viewpoint, the design, construction and instrumentation of the Hybrid III tibia, and the related measures of injury risk, specified in Directive 96/79/EC, present some difficulties. The paper briefly describes limitations associated with the design of the tibia, the standard instrumentation, and the currently regulated measures of injury risk. Given the anticipated delay before more advanced legs become available, interim means of increasing the utility of current data are suggested. Improvements to the instrumentation and further modification of the ankle characteristics are briefly discussed. (A)