Abstract: This disclosure relates to a surgical tool configured for holding an implant includes an inner rod and a sleeve. The inner rod includes a rod portion and a holding portion. The holding portion is located at one end of the rod portion and has a first accommodation space configured for accommodating at least part of the implant. The sleeve includes a sleeving portion and a retaining portion. The sleeving portion is slidably sleeved on the rod portion of the inner rod. The retaining portion is located at one end of the sleeving portion and selectively presses against the holding portion. The inner rod further includes at least one fin portion protruded from the holding portion and located in the first accommodation space for being inserted into at least one slot of the implant.

Abstract: A CAD system enables a designer to freely modify a model of a design without regenerating a history of the model, as in traditional parametric feature based modeling. The CAD system automatically determines whether the modifications to the model invalidate current features associated with the model and whether the modifications create new features that should be added to the model. Such a CAD system enables a designer to quickly edit designs and simultaneously preserve design intent without requiring the significant computational resources of historical based approaches that regenerate a geometry upon every edit made by a designer.

Abstract: A CAD system enables a designer to freely modify a model of a design without regenerating a history of the model, as in traditional parametric feature based modeling. The CAD system automatically determines whether the modifications to the model invalidate current features associated with the model and whether the modifications create new features that should be added to the model. Such a CAD system enables a designer to quickly edit designs and simultaneously preserve design intent without requiring the significant computational resources of historical based approaches that regenerate a geometry upon every edit made by a designer.