Abstract: A surgical model simulating certain aspects of the natural anatomical joint is made by first providing a male mould conforming externally to the general anatomy of an internal cavity of the joint. A coating of resilient impermeable penetrable material is applied over the male mould. The coating is removed from the male mould to form an open capsule. A closure is provided for the capsule attached to the open capsule so as to form an impermeable penetrable capsule, the capsule conforming internally to the general anatomy of the internal cavity of the joint and containing simulated joint components. The capsule is arranged within a mould, the mould being at least partly lined with a penetrable outer skin material, and the capsule is embedded in a penetrable packing material. Finally, the model is removed from the mould.