New York—March 11, 2014
Each year, more than 340,000 people suffer a broken hip in the United States. The femoral neck, the area just below the ball of the hip’s ball-and-socket joint, is the most common site of fracture, accounting for 45 to 53 percent of cases. People with this type of injury are at high risk of complications because the blood supply to the fractured portion of the bone is often disrupted. The concern is that the decreased blood supply will lead to non-healing or the death of bone cells, known as osteonecrosis.
Researchers at Hospital for Special Surgery developed a specially sequenced, contrast-enhanced MRI to identify potential problems so doctors can intervene early and prevent further damage to the joint. “This new MRI greatly improves the visualization of bone and soft tissue when there is metal in a joint, such as the screws used to repair a hip fracture,” explained Hollis G. Potter, M.D., Chairman of the Department of Radiology and Imaging at HSS.
A study on this subject, titled “Femoral Head Osteonecrosis Following Anatomic Stable Fixation of Femoral Neck Fractures: An in-vivo MRI Study” was presented at the annual meeting of the American Academy of Orthopaedic Surgeons (AAOS) in New Orleans on March 11, 2014.
The Department of Radiology and Imaging at HSS is known internationally as a premier center for world class musculoskeletal clinical and research imaging. “Imaging is a vital component of the integrated care system provided by HSS,” said Dr. Potter. “Our team is constantly optimizing the ability to image the earliest signs of a musculoskeletal condition, disease progression and/or healing.”
Despite advances in surgical hardware and techniques, femoral neck fractures remain a significant clinical challenge. The primary complications arising from femoral neck fractures are non-union and osteonecrosis, which occurs when the blood supply to the bone is disrupted. This causes bone cells to die, which can destroy the joint and lead to arthritis.
With respect to femoral neck hip fractures, this is the first MRI that can “see through” surgical screws to detect early signs of osteonecrosis, so that interventions can be initiated before there is further damage, such as collapse of the bone or osteoarthritis.
In the study, patients had an MRI known as a “multi-acquisition variable-resonance image combination,” or MAVRIC MRI, three months and 12 months after surgery. “The MAVRIC MRI provided us with information that could not be ascertained from x-rays or a standard MRI,” Dr. Potter explained. “A special 3-D fast spin echo technique minimized distortion caused by metal screws used to repair the fracture, facilitating assessment of the hip joint and any potential problems concerning osteonecrosis or non-union.”
MRI revealed decreased blood flow to the injured area and osteonecrosis in 80 percent of patients in the superomedial quadrant of the femoral head. However, despite these findings, patients demonstrated excellent radiographic and functional outcomes. Researchers attributed this to a surgical technique that entailed stabilizing the broken bones with screws and restoring the fracture to the correct alignment and normal anatomical position.
About HSS | Hospital for Special Surgery
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 ninth consecutive year) and No. 3 in rheumatology by U.S.News & World Report (2018-2019). Founded in 1863, the Hospital has one of the lowest infection rates in the country and was the first in New York State to receive Magnet Recognition for Excellence in Nursing Service from the American Nurses Credentialing Center four consecutive times. The global standard total knee replacement was developed at HSS in 1969. 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. In 2017 HSS provided care to 135,000 patients and performed more than 32,000 surgical procedures. People from all 50 U.S. states and 80 countries travelled to receive care at HSS. 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. The HSS Global Innovation Institute was formed in 2016 to realize the potential of new drugs, therapeutics and devices. The culture of innovation is accelerating at HSS as 130 new idea submissions were made to the Global Innovation Institute in 2017 (almost 3x the submissions in 2015). The HSS Education Institute is the world’s leading provider of education on the topic on musculoskeletal health, with its online learning platform offering more than 600 courses to more than 21,000 medical professional members worldwide. Through HSS Global Ventures, 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.