Victor M. Spitzer

The Visible Human Male: A Technical Report

The National Library of Medicines Visible Human Male data set consists of digital magnetic resonance (MR), computed tomography (CT), and anatomic images derived from a single male cadaver. The data set is 15 gigabytes in size and is available from the National Library of Medicine under a no-cost license agreement. The history of the Visible Human Male cadaver and the methods and technology to produce the data set are described.

Three-Dimensional Mechanics, Kinematics, and Morphology of the Knee Viewed in Virtual Reality

T he premise of this article, and the scientific exhibit upon which it is based, is that the morphologic shape of the distal aspect of the femur and its relation to the tibia and the patella dictates the kinematics of the knee. The morphologic and kinematic characteristics of the knee presented in earlier exhibits1,2 at the 2001 and 2003 Annual Meetings of the American Academy of Orthopaedic Surgeons demonstrated the following relationships. The location and orientation of the femoral sulcus is lateral to the midplane between the femoral condyles and is oriented between the anatomic and mechanical axes of the femur (Figs. 1-A and 1-B). The center of the femur in cross section is offset, medial and anterior, to the center of the tibia, and these offset cross sections are rotated relative to each other in the pathologic knee (Fig. 2). A single, fixed flexion-extension axis of the knee is centered in the asymmetric cylindrical femoral condyles (Fig. 3). These and other observations1-8 of distal femoral morphology and their relationship to knee kinematics form the basis for the additional studies in the present article. These new studies relate the morphology of the femur (condyles and epicondyles) and the axis of the limb (mechanical axis) to the location and orientation of the flexion-extension axis of the knee in three-dimensional space. The clinical importance of this work is found in its application to ligament reconstruction and total knee arthroplasty. Despite improvements in design, implant alignment in total knee arthroplasty remains a crucial factor in the function and longevity of the implant9-11. It has been demonstrated that malalignment causes increased wear of the implant and premature failure of the construct11-14. Most contemporary implants are designed to be aligned to …

The visible human dataset: The anatomical platform for human simulation †

One goal of a medical school education is to teach the anatomy of the living human. With the exception of some surface anatomy, the morphology education that goes on during a surgical procedure, and patient observation, live human anatomy is most often taught by simulation. Medical anatomy courses utilize cadavers to approximate the live human. Case‐based curricula simulate a patient and present symptoms, signs, and history to mimic reality for the future practitioner. Radiology has provided images of the morphology, function, and metabolism of living humans but with images foreign to most novice observers. With the Visible Human database, computer simulation of the live human body will provide revolutionary transformations in anatomical education. Anat. Rec. (New Anat.) 253:49‐57, 1998.

Three-dimensional Morphology And Kinematics Of The Distal Part Of The Femur Viewed In Virtual Reality: Part Ii

The purpose of this exhibit is to demonstrate, with conventional and virtual images, the three-dimensional shape of the naturally asymmetric distal part of the femur, illustrating the cylindrical axis of the femoral condyles relative to the conventional (mechanical, anatomic, and epicondylar) axes of the lower limb and knee. The relationships between morphologically and experimentally determined rotation axes are illustrated. This study provides kinematic and morphologic validation for a single cylindrical flexion-extension axis of the knee. The clinical implications of a single flexion axis of the knee for alignment and soft-tissue balance in total knee arthroplasty, as well as the position and tension of a graft in anterior cruciate ligament reconstruction, are demonstrated with the aid of illustrations from the Visible Human Project at the National Library of Medicine as well as images from the University of Colorado Center for Human Simulation. The morphologic shape of the distal part of the femur and its relation to the tibia and the patella dictate the kinematics of the knee. Work presented in an earlier American Academy of Orthopaedic Surgeons exhibit1 demonstrated that the lateral tracking of the patella is reflected in the trochlear groove lying lateral to the mid-plane and oriented between the mechanical and anatomic axes of the femur in the coronal plane2,3. The posterior-lateral offset of the tibia relative to the femur in the normal knee and the external rotation of the tibia relative to the femur in the abnormal knee were also documented in the transverse plane4-7. The asymmetric cylindrical morphology of the femoral condyles posterior to the coronal plane, another morphologic feature of the distal aspect of the femur demonstrated in the earlier exhibit1, dictates the location of the flexion-extension axis of the knee and drives the kinematics …

Three-Dimensional Morphology of the Distal Part of the Femur Viewed in Virtual Reality

The morphologic shape of the distal part of the femur dictates the shape, orientation, and kinematics of prosthetic total knee replacement. Traditional prosthetic designs incorporate symmetric femoral condyles with a centered trochlear groove. Traditional surgical techniques center the femoral component to the distal part of the femur and position it relative to various bone landmarks. However, failure patterns documented in retrieval studies1,2, case series3, and kinematic studies demonstrate how traditional designs and surgical techniques reflect a poor understanding of distal femoral morphology and knee kinematics. It has been shown that the flexion/extension axis of the knee is fixed within the femur and that the articular surfaces of the condyles are circular in profile4,5. Ligament length patterns are significantly altered by abnormal axial alignment when a hinged knee brace is used6. It is expected that a malaligned femoral component would have the same effect in total knee arthroplasty. The purpose of this report is to demonstrate, with conventional images and with interactive animations in virtual reality, the three-dimensional shape of the naturally asymmetric distal part of the femur, with illustration of the sulcus axis of the trochlear groove and the flexion/extension axis of the condyles relative to conventional axes (mechanical, anatomic, epicondylar, and posterior condylar). Correlations between the morphologically determined rotation axes and experimentally determined kinematic axes are illustrated. Eighty-five mummified cadaveric knees were measured with a stereotactic micrometer (Fig. 1)7. The location and orientation of the sulcus were obtained by repeated horizontal passes of the stereotactic stylus over the distal part of the femur, beginning at the top of the articular surface and progressing down to the intercondylar notch (Fig. 2). With each horizontal pass, the lowest depression of the trochlea (sulcus) was identified by …

The Visible Human ® at the University of Colorado 15 years later

The Visible Human has come through ages, providing a foundation of photorealistic anatomy for learner-centered, interactive education. Pathways for improvement of the Visible Human process for reverse engineering the macrostructure of the human body have been developed to provide higher resolution and decreased production time for segmentation and modeling human form. The assignment of physical properties, the development of algorithms for the interaction of surgical tools with this virtual anatomy and the availability of high-fidelity haptic interfaces provide the basis for fully immersive surgical training and certification in an environment that is zero direct-risk to patients. Interactive journal publishing, 3D stereoscopic anatomical visualization software and surgical simulators, all based on the Visible Human, the history of the Project and its utilization and provide a framework for its evolution and role in delivering education, training, certification and credentialing through virtual reality to the health care workforce of tomorrow.