Dang Orthopedics is studying the biomechanics of the spine and shoulder through realistic mathematical representations of human anatomy. This work is in collaboration with researchers at the University of California, San Francisco, and the New England Musculoskeletal Institute at the University of Connecticut Health Center. The detailed spine model let Dang Orthopedics simulate a surgical procedure in order to measure loads and stresses on adjacent vertebrae. A procedure called discectomy and fusion may be necessary when conventional therapies fail to treat pain or weakness caused by mechanical deformation or inflammation of the nerve roots in the neck.

In a procedure intended to reduce back pain, surgeons remove the disc between affected vertebrae and stabilize the spine using bone grafts or metal plates and screws. Although the operation works, it tends to accelerate arthritis in the rest of the spine. A theory says increased strain in the remaining motion segments of the spine after surgery contributes to arthritis, but measuring the strain in patients has been difficult and tests on anatomic specimens inconclusive.

A detailed finite-element (FE) model of the human skeleton may now let researchers estimate the strain put on healthy vertebrae during surgery. The 91,000-element model, originally developed by Toyota for auto-safety studies, contains detailed spines and vertebrae. Once Alan Dang, president of Dang Orthopedics had access to the cervical spine model, he used finite-element software to isolate the biomechanical effects of cervical spine fusion, a common procedure to ease back pain.

Setting up the detailed and large FE models, as well as zooming in and out and rotating sometimes several models and views at one time, required heavy-duty graphics hardware. Dang selected Nvidia GPUs for the task of driving several displays at once.

"The GPUs drive several monitors well, some with 30-in displays running at 2,560 x 1,600 resolutions,” says Dang. “The graphics hardware let us simultaneously load several documents and 3D models without running out of graphics power, or compromising visual fidelity or system stability. It let us focus on the research instead of troubleshooting the equipment.”

As a result of Dang’s work, surgeons have quantitative data on the biomechanical effects at adjacent vertebrae following cervical spine fusion. This information will guide future research in artificial disc replacements and hopefully reduce the incidence and severity of post-surgical complications.