As the body of knowledge concerning human anatomy and physiology continues to grow, new techniques must emerge to convey it more efficiently to future health care professionals. Computer simulation, interaction and visualization technologies are now being used in the development of virtual training environments. This paper presents a real-time virtual surgical simulator that integrates scientific visualization tools into a surround-screen projection-based (SSPB) immersive environment. This environment focuses on procedures for the lower limbs; however, the techniques described can be applied to other portions of the body. The research consists of three phases: environment modeling, volume visualization and immersive surgical simulation. Environment modeling involved modeling an operating room with all of the relevant elements. The volume visualization phase required the application of marching cubes and decimation techniques to the Visible Human Project (VHP) dataset to generate models of the lower limbs. The simulator integrated modeling and volume visualization to facilitate the rehearsal of medical procedures and interaction with medical information. Interactive cutting, suturing and X-Ray CT placement over the virtual patient's legs were used to probe underlying structures. The simulator is intended to aid medical students in learning anatomy, physiology and radiological analysis without jeopardizing patient care.