Hospital for Special Surgery (HSS) in New York City — ranked the number one orthopedic hospital in the United States for 16 consecutive years by U.S. News & World Report — is deploying a technology that could fundamentally change how orthopedic surgical decisions are made, documented, and disputed in workers’ compensation cases. The tool is called a “digital twin,” and it is moving from the research lab into everyday clinical practice.
A digital twin is a virtual replica of a patient’s own anatomy, built from advanced 3D MRI imaging and powered by physics-based computational modeling. In orthopedics, this means a surgeon can create a detailed, patient-specific computer model of an injured knee — including bones, cartilage surfaces, ligaments, and the mechanical relationships between them — and then run simulations on that model before operating.
The surgeon can test different surgical approaches on the virtual knee: tighten or loosen virtual ligaments, reposition virtual implant components, simulate how the joint will behave under load after various types of repair — all without touching the actual patient. The goal, as HSS Digital Twin Program Director Dr. Andrew Pearle has described it, is to move orthopedics beyond one-size-fits-all surgical planning toward truly individualized treatment based on each patient’s unique anatomy and biomechanics.
HSS received a $10 million gift in November 2025 from Lauren and Robert Steers to develop the HSS Digital Twin Platform into a four-year clinical program. The institution’s stated goal is that within four years, every patient who comes to HSS with a relevant clinical problem will receive a digital twin of their knee. The multidisciplinary team includes orthopedic surgeons, radiologists, biomechanical engineers, and artificial intelligence specialists.
The platform is already being applied to clinical cases. One of the initial applications has been evaluating patients who need ACL revision surgery — a repeat procedure after a prior ACL repair has failed. In these complex cases, surgeons must determine whether the patient would also benefit from a slope-reducing tibial osteotomy, a procedure that reshapes the angle of the shinbone to reduce the mechanical forces that contributed to the original graft failure.
Traditionally, this determination has relied on the surgeon’s clinical judgment, standard imaging, and experience. With the digital twin, the surgical team can simulate both options — revision alone versus revision plus osteotomy — on the patient’s own virtual anatomy and compare the predicted biomechanical outcomes before making a recommendation.
The platform also integrates additional data beyond imaging: patient gender, activity level, the type of physical demands the patient faces (including occupational demands), and neuromuscular control information. As HSS researchers have described it, the more data fed into the twin, the more precise and personalized the insights become.
HSS is not working alone. The institution is collaborating with other medical centers and organizations to scale the platform, and the underlying technologies — computational modeling, physics-based simulation, AI-enhanced imaging analysis — are advancing rapidly across the orthopedic field. Medscape reported in April 2026 that the platform represents a new frontier in precision orthopedic care that may extend beyond surgical planning into injury prevention.
The trajectory is clear: orthopedic surgery is moving from population-based decision-making toward individualized, simulation-driven planning. For workers’ comp, that means the medical evidence supporting — or challenging — surgical recommendations in injury claims is about to become significantly more sophisticated. Adjusters, attorneys, utilization review teams, and medical evaluators who understand what a digital twin is, what data it produces, and what its limitations are will be better positioned to handle the claims that follow.