HSS Uses Patient-Specific Technologies to Help People with Bowed Legs Delay Knee Replacement

NASHVILLE, Tenn.--(BUSINESS WIRE)--Hospital for Special Surgery (HSS) presented findings at the American Orthopaedic Society for Sports Medicine (AOSSM) annual meeting demonstrating how surgeons are revitalizing a historic orthopedic procedure to help patients with bowed legs restore proper limb alignment, enhance knee function, and potentially avoid knee replacement surgery through the use of cutting-edge technology and improved patient outcomes.

First introduced in the late 1800’s, the procedure, called knee osteotomy, involves cutting and reshaping the shinbone or thighbone to relieve pressure on the knee joint. It was initially used as a common treatment for arthritis and later for various orthopedic conditions and injuries, but it became less popular with the advent of the modern knee replacement in the 1970s. Nevertheless, surgeons continued to use and refine the technique. Today, the approach is used to fix bowleg deformity and prevent the need for knee replacement surgery, which carries a higher risk of complications particularly in people under age 50.

Bowleg deformity is an incorrect alignment around the knee that can affect people of all ages. The many causes of bowleg syndrome range from illnesses such as Blount’s disease to improperly healed fractures and vitamin deficiencies.

Patients who had knee osteotomy reported positive outcomes and significant improvements in quality of life, according to a comprehensive review of the literature on the technique that was led by Anil S, Ranawat, MD, Chief of the Hip and Knee Division of the Sports Medicine Institute at Hospital for Special Surgery (HSS). High patient satisfaction rates included less pain, better movement, and very few complications after the surgery, which helped delay or avoid the need for knee replacement in the vast majority of cases. The results are being presented at the AOSSM annual meeting.

“The development of new technologies, such as digital software planning, advanced CT imaging, and other patient-specific tools, is enabling us to resolve patients’ knee pain and preserve their knee function for a longer period of time,” explains Dr. Ranawat. “This modern evolution of an old operation has helped us tailor these procedures so that they are done in the safest, most precise way possible.”

Osteotomy is no longer a one-size-fits-all approach. “These improved outcomes were made possible by the advent of patient-specific instrumentation (PSI), in which a surgeon uses a patient’s CT scan and digital software to do a virtual surgery and plan the ideal operation tailored to the individual’s anatomy and needs,” explains Dr. Ranawat, an expert in joint restoration and preservation.

The development of knee replacement surgery in the 1970s caused surgeons to recommend knee osteotomy less frequently, however younger patients under age 50 tended not to do well with it due to high rates of infection and other complications. In addition, knee replacements have a life span of about 15 to 20 years, so younger patients often need a second operation when their knees fail.

“New patient-specific technologies have revolutionized the safety and precision of osteotomy, even more than knee replacement, so now if we do an osteotomy on a 25- or 30-year-old, the operation could last 40 years,” says Dr. Ranawat. “This is why joint preservation has been our goal at HSS over the last two decades. We are taking a much more proactive approach to offering knee osteotomy in younger patients to ideally avoid knee replacement altogether.”

HSS has been a thought leader in knee osteotomy for many years and is using all different forms of modern technology to improve surgical precision and patient outcomes. Dr. Ranawat and his colleagues will continue to build on the benefits of PSI, integrating the latest tools and technology to redefine joint preservation.

“We want our younger patients to know they don’t have to live with pain or rush into a knee replacement,” said Dr. Ranawat. “This is about preserving function and quality of life for the long haul. Incorporating artificial intelligence, machine learning, and advanced imaging will lead to smarter PSI systems​ and open the door to robotic-assisted surgeries that could revolutionize knee osteotomy in the future,” he says.

About HSS

HSS is the world’s leading academic medical center focused on musculoskeletal health. At its core is Hospital for Special Surgery, nationally ranked No. 1 in orthopedics (for the 15th consecutive year), No. 3 in rheumatology by U.S. News & World Report (2024-2025), and the best pediatric orthopedic hospital in NY, NJ and CT by U.S. News & World Report “Best Children’s Hospitals” list (2024-2025). In a survey of medical professionals in more than 20 countries by Newsweek, HSS is ranked world #1 in orthopedics for a fifth consecutive year (2025). Founded in 1863, the Hospital has the lowest readmission rates in the nation for orthopedics, and among the lowest infection and complication rates. HSS was the first in New York State to receive Magnet Recognition for Excellence in Nursing Service from the American Nurses Credentialing Center five consecutive times. An affiliate of Weill Cornell Medical College, HSS has a main campus in New York City and facilities in New Jersey, Connecticut and in the Long Island and Westchester County regions of New York State, as well as in Florida. In addition to patient care, HSS leads the field in research, innovation and education. The HSS Research Institute comprises 20 laboratories and 300 staff members focused on leading the advancement of musculoskeletal health through prevention of degeneration, tissue repair and tissue regeneration. In addition, more than 200 HSS clinical investigators are working to improve patient outcomes through better ways to prevent, diagnose, and treat orthopedic, rheumatic and musculoskeletal diseases. The HSS Innovation Institute works to realize the potential of new drugs, therapeutics and devices. The HSS Education Institute is a trusted leader in advancing musculoskeletal knowledge and research for physicians, nurses, allied health professionals, academic trainees, and consumers in more than 165 countries. The institution is collaborating with medical centers and other organizations to advance the quality and value of musculoskeletal care and to make world-class HSS care more widely accessible nationally and internationally. www.hss.edu.