U.S. News evaluated nearly 4,500 hospitals in 14 specialties. Hospital performance was assessed based on various measures, including patient outcomes, level of nursing care, patient-reported experience, and available technology such as computer-assisted orthopedic surgery. The methodology factored in data from the Centers for Medicare & Medicaid Services, professional organizations, and medical specialists.

“We are proud to once again be recognized as a leader in orthopedics and rheumatology,” said HSS President and CEO Bryan T. Kelly, MD, MBA. “This distinction reflects the extraordinary expertise, dedication, and collaboration of the entire HSS team. For patients across the New York metropolitan region, it is also a powerful validation that the best orthopedic care in the country is available right here in their community. Through comprehensive musculoskeletal care, we help patients preserve mobility, enhance their quality of life, and extend their healthspan so they can continue doing what they need and love to do.”

“This recognition from U.S. News reflects HSS’s unwavering commitment to advancing musculoskeletal health through clinical excellence, innovation, and patient-centered care,” said Douglas E. Padgett, MD, surgeon-in-chief and medical director of HSS. “Perhaps the greatest measure of our impact is the trust of patients who travel to HSS from across the country and around the world seeking care have placed in us. This distinction reflects our dedication to achieving exceptional outcomes and our belief that preserving movement is the foundation of longevity and quality of life.”

Patients come to HSS from all 50 states and more than 100 countries, often for both common and complex medical conditions or challenging surgeries requiring highly specialized care. As a global destination for orthopedic and rheumatologic care, HSS brings together world-renowned physicians, advanced treatment approaches, and multidisciplinary teams dedicated to delivering personalized, evidence-based care for patients of all ages and activity levels.

“Our rankings reflect the extraordinary expertise, dedication, and innovation of the physicians, scientists, researchers, and care teams who make HSS a leader in rheumatology,” said Anca D. Askanase, MD, MPH, Chair of the Department of Medicine and Chief of the Division of Rheumatology at HSS. “Through groundbreaking research, advanced therapies, and highly personalized care, we are helping to transform the lives of patients living with complex autoimmune and inflammatory diseases.”

“The pace of discovery in musculoskeletal medicine is accelerating at an unprecedented rate,” said Joel Press, MD, Physiatrist-in-Chief at HSS. “Advances in artificial intelligence, data science, and precision medicine are helping researchers uncover new insights faster and translate those discoveries into more effective, personalized care. With HSS’s singular focus on musculoskeletal health and unmatched depth of clinical expertise, we are uniquely positioned to turn innovation into meaningful improvements in outcomes for patients everywhere.”

As the world’s leading academic medical center specializing in musculoskeletal health, HSS maintains among the lowest hospital readmission rates for orthopedics in the nation, and among the lowest rates for infection and complications. HSS is the worlds most awarded hospital in orthopedics by Newsweek each year since the “World’s Best Specialized Hospitals” survey was introduced in 2020.

In 2025, HSS clinicians and surgeons provided specialized care to more than 258,016 patients with orthopedic or rheumatologic conditions, such as pain or injury to the back, neck, or joints; osteoarthritis; rheumatoid arthritis; lupus; scleroderma; and psoriatic arthritis. HSS performed more than 45,864 orthopedic surgical procedures in 2025.

HSS is the official hospital of and provides team physicians to more than 25 high-performing sports teams and leagues, including the New York Giants, New York Knicks, New York Liberty, Brooklyn Nets, New York Mets, New York Red Bulls, TCS New York City Marathon, National Basketball Players Association, Major League Pickleball, US Youth Soccer, and UFC. It is designated a Medical Center of Excellence by Fédération Internationale de Football Association (FIFA).

Lymphatic vessels act as communication highways, carrying signals from tissues to the immune system to alert it to infection, injury, or disease. When this system does not function properly, the body may struggle to fight infections, respond to vaccines, repair tissue, or control inflammation.

The new findings show that Langerhans cells play a key role during early life by helping lymphatic vessels grow and develop properly in the skin. This early “setup” has long-term consequences, influencing how well the immune system functions later in life.

“Our study shows that immune cells in the skin do much more than respond to threats—they help build the infrastructure the immune system depends on,” said senior author Theresa T. Lu, MD, PhD, who holds the St. Giles Chair for Research in the HSS Research Institute and is a member of Pediatric Rheumatology at HSS. “If this process is disrupted early in life, it can have lasting effects on immune health. Our results also underscore the critical role of skin health in regulating lymphatic vessel development and immune system function in health and disease.”

“These findings advance our understanding of how early-life biological processes influence long-term immune function,” explained JiHyun Sim, PhD, first author and Postdoctoral Fellow at HSS. “We are hoping to further understand if this physiologic process is disrupted to contribute to autoimmune disease.”

Key Findings

• Early-life development matters: Proper formation of lymphatic vessels in childhood is essential for strong immune responses in adulthood.
• New role for Langerhans cells: Beyond their known immune functions, these cells help guide the growth and programming of lymphatic vessels.
• Long-term impact: When Langerhans cells are reduced or impaired early in life, the immune system may be less effective later on.

Implications for Patients and Providers

The research suggests that conditions affecting skin health in early life—such as severe sunburn, burns, or certain autoimmune diseases like lupus—could interfere with Langerhans cells and, in turn, disrupt lymphatic development. This may contribute to weaker immune responses later in life, including reduced effectiveness of vaccines, increased susceptibility to infections, impaired healing, and potential autoimmune complications.

“These findings highlight the importance of protecting skin health early in life,” said Dr. Lu. “They also open the door to new approaches that could strengthen immune function by targeting the lymphatic system.”

A New Way of Thinking About Immune Health

The study adds to a growing body of evidence showing that early-life health and environmental factors can shape disease risk in adulthood. It also identifies a previously unknown mechanism by which immune cells influence tissue development—not just immune activation.

By uncovering how Langerhans cells regulate lymphatic vessel growth, researchers hope to pave the way for future strategies to improve immune responses and prevent disease across the lifespan.

Authors: JiHyun Sim, PhD, Richard Bell, PhD, Yurii Chinenov, PhD, Zhonghui Feng, PhD, Susan Chyou, BA, William D. Shipman, MD, PhD, Lionel Ivashkiv, MD, Theresa T. Lu, MD, PhD

The study, published in Science Translational Medicine, reveals that a subset of immune cells known as SPP1ʰⁱ macrophages work in tandem with structural cells and protein scaffolds to promote excessive tissue expansion in the joints of patients with RA.

RA is a chronic autoimmune disease that causes inflammation of the synovium—the tissue lining the joints—leading to pain, swelling, and eventual damage to cartilage and bone. While current therapies largely focus on controlling inflammation, the mechanisms that drive the abnormal growth of synovial tissue—and its invasive portion, known as pannus, which erodes cartilage and bone—have remained poorly understood.

A New Model of Tissue Growth in RA

Using advanced spatial transcriptomics to analyze human tissue samples, the HSS research team discovered that SPP1ʰⁱmacrophages cluster within fibrin-rich niches in the synovium. Fibrin, a protein typically involved in blood clotting and wound healing, appears to act as a temporary scaffold that supports new tissue formation.

Within these niches, the macrophages were found to:

• break down fibrin scaffolds through enzymatic activity and cellular uptake;
• stimulate nearby fibroblasts, key structural cells, to proliferate; and
• promote tissue remodeling and expansion independent of traditional inflammatory pathways.

“This work suggests that rheumatoid arthritis is not only driven by inflammation, but also by dysregulated tissue repair processes,” said Laura Donlin, PhD, senior author and scientist at the HSS Research Institute. “We are seeing a coordinated interaction between immune cells, structural cells, and the extracellular matrix that fuels abnormal growth.”

Beyond Fibrosis: A Distinct Pathway

Interestingly, while SPP1ʰⁱmacrophages resemble cells involved in fibrotic diseases such as lung or liver fibrosis, the RA tissue environment lacks the dense collagen buildup characteristic of fibrosis. Instead, the researchers describe this process as “pro-generative” tissue remodeling, more closely resembling wound healing gone awry.

Therapeutic Implications

The findings also suggest that targeting SPP1ʰⁱmacrophages and their signaling pathways could represent a new therapeutic approach. The study highlights the role of IL-6 signaling in sustaining these cells, offering further insight into why IL-6–targeting therapies, already used in RA, may be particularly effective in certain patient populations.

“Current treatments focus on suppressing inflammation, but our findings point to additional pathways that drive disease progression,” said Dr. Donlin. “Targeting these tissue remodeling processes could open the door to more precise and effective therapies.”

Broader Impact

The study’s findings may extend beyond RA. Similar immune cell populations and fibrin-based remodeling processes have been implicated in other conditions, including interstitial lung disease, lupus, cancer, and traumatic injury, suggesting a broader role for this pathway in human disease.

“We welcome Dr. Askanase to HSS and we are confident that her leadership and vision will help us to advance excellence in clinical care, research, education, and community service through the Department of Medicine and Division of Rheumatology,” said Bryan T. Kelly, MD, MBA, president and CEO and Surgeon-in-Chief Emeritus at HSS. “HSS is also deeply grateful for Dr. Bridges, a highly respected physician-scientist whose leadership and legacy has profoundly advanced patient care and scientific discovery at HSS.” 

Dr. Askanase was selected following a rigorous, nationwide search led by an external executive search firm, which attracted a highly competitive pool of accomplished candidates from leading academic medical centers. She brings more than two decades of leadership in academic rheumatology. From 1999 to 2013, Dr. Askanase practiced at NYU Langone Health and the Hospital for Joint Diseases, where she developed a strong appreciation for the close integration of orthopedics and rheumatology in caring for patients with complex musculoskeletal disease. Since 2014, she has served on the faculty of Columbia University Irving Medical Center, where she is a Professor of Medicine and founded and directs the Columbia Lupus Center. 
“Dr. Askanase is a distinguished and highly respected clinician-scientist who has made significant contributions to the fields of rheumatology and lupus. She approaches complex cases with extraordinary dedication and compassion and is a powerful advocate for populations disproportionately affected by rheumatic diseases,” said Douglas E. Padget, MD, Surgeon-in-Chief and Medical Director at HSS. “Her leadership will be an invaluable addition to our community. Her appointment underscores HSS’s commitment to the advancement of patient care practices by recruiting outstanding physician leaders in our clinical specialties.” 

A globally recognized clinician-scientist, Dr. Askanase has led or participated in more than 150 clinical investigations and has played a significant role in shaping national and international standards for rheumatologic care through leadership positions with the American College of Rheumatology, the Lupus Foundation of America, the Lupus Research Alliance, and the Systemic Lupus International Collaborating Clinics network. She is a clinician, diagnostician, and researcher specializing in complex Systemic Lupus Erythematosus (SLE), more commonly known as lupus. Her research in SLE encompasses epidemiology, outcomes research, and therapeutic clinical trials. Ongoing government-funded projects include the use of optical imaging to evaluate subclinical arthritis, the development of virtual lupus disease activity measures, and lupus education outreach to disparate populations. Dr. Askanase has been at the vanguard of cell therapy research and treatments for SLE and other autoimmune diseases; and she is the Global PI of several novel cell therapy programs and an Investigator Initiated Study to evaluate the safety and efficacy of CAR-NKs. Her work in advancing patient-centered care models, clinical trials in autoimmune disease, and cell therapy initiatives aligns closely with HSS’s commitment to innovation and excellence across the continuum of musculoskeletal care. 

In her role at HSS, Dr. Askanase will provide strategic leadership in Rheumatology while overseeing the Department of Medicine, with a focus on strengthening collaboration across specialties, advancing clinical and translational research, and supporting excellence in patient care, education, and mentorship. 

“I feel privileged to have the opportunity to lead the renowned HSS Division of Rheumatology and Department of Medicine as we continue to advance and transform the science and practice of rheumatology and its related specialties,” said Dr. Askanase. “This is a pivotal moment for our field, with rapid progress in diagnostics, therapeutics, and personalized approaches to care. At HSS, we are uniquely positioned to translate these innovations into meaningful improvements in patients’ lives. Working alongside our esteemed colleagues in Orthopedics, we have an unparalleled opportunity to shape the future of musculoskeletal health worldwide—through clinical excellence, groundbreaking research, and a shared commitment to delivering the highest quality of care.” 
 

U.S. News evaluated nearly 4,500 hospitals in 15 specialties. Hospital performance was assessed based on various measures, including patient outcomes, level of nursing care, patient-reported experience, and available technology such as computer-assisted orthopedic surgery. The methodology factored in data from the Centers for Medicare & Medicaid Services, the American Hospital Association, professional organizations, and medical specialists.

“We are once again honored to be recognized as a leader in our specialties of orthopedics and rheumatology,” said HSS President and CEO Bryan T. Kelly, MD, MBA. “This reflects the skill and dedication of every member of the HSS team, who work together to help people get back to what they need and love to do better than any other place in the world.”

“The U.S. News rankings underscore HSS’s continued leadership and commitment to musculoskeletal health, reflecting 162 years of clinical excellence, innovation, and patient-centered care,” said Douglas E. Padgett, MD, surgeon-in-chief and medical director of HSS. “Our consistent recognition as a top hospital highlights our steadfast dedication to maintaining the highest standards of evidence-based care.”

Patients come to HSS from all 50 states and more than 100 countries, often for complex medical conditions or challenging surgeries requiring highly specialized care.

“When faced with a challenging rheumatologic disease, every patient wants a rheumatologist they can trust,” said S. Louis Bridges, Jr., MD, PhD, physician-in-chief and chief of the Division of Rheumatology at HSS. “The high rating of HSS Rheumatology demonstrates clinical excellence made possible by our strong dedication to best practices and personalized care, and by our commitment to advancing musculoskeletal medicine through research, education, and innovation.”

As the world’s leading academic medical center specializing in musculoskeletal health, HSS maintains among the lowest hospital readmission rates for orthopedics in the nation, and among the lowest rates for infection and complications. HSS has been named No. 1 in the world for orthopedics by Newsweek each year since the “World’s Best Specialized Hospitals” survey was introduced in 2020.

HSS is one of only three US hospitals ranked No. 1 both nationally and globally in any specialty.

In 2024, HSS clinicians and surgeons provided specialized care to more than 248,917 patients with orthopedic or rheumatologic conditions, such as pain or injury to the back, neck, or joints; osteoarthritis; rheumatoid arthritis; lupus; scleroderma; and psoriatic arthritis. HSS performed more than 43,000 orthopedic surgical procedures in 2024.

HSS is the official hospital of and provides team physicians to more than 25 high-performing sports teams and leagues, including the New York Giants, New York Knicks, New York Liberty, Brooklyn Nets, New York Mets, New York Red Bulls, TCS New York City Marathon, National Basketball Players Association, Major League Pickleball, US Youth Soccer, and UFC. It is designated a Medical Center of Excellence by Fédération Internationale de Football Association (FIFA).

* Copyright © 2025 U.S. News & World Report, L.P. Data reprinted with permission from U.S. News.

RA is a chronic disease characterized by inflammation in the synovium, the tissue that covers the inner surface of the joint cavity. Although usually accompanied by joint pain, swelling and deterioration, the level of inflammation varies from patient to patient, potentially requiring customized treatment plans. “What is surprising to us is that there are some patients who have clinical remission, yet continue to experience pain and show radiographic progression of the disease with high levels of synovial inflammation, while others have high disease activity with many swollen and tender joints and little inflammation in the synovial tissue” said Susan M. Goodman, MD, rheumatologist at HSS and principal investigator of the study. She explained that even when standard tests suggest the disease is under control, the joint fluid can still show high levels of inflammation. “By analyzing synovial fluid characteristics, we expected it might give us some insight into the disparity between disease progression and apparent remission,” she added.

The team analyzed samples from 64 patients with RA, 90.6% of whom were women, and with a median age of 65.3 ±11.7 years. The physicians collected synovial fluid samples to analyze and compare with the synovial tissue biopsy counterpart, which defines the inflammatory profile of the disease.

Dr. Goodman and the team measured the total white blood cell count, as well as the percentage of neutrophils, lymphocytes and monocytes in each synovial fluid sample. They then compared those findings to two additional key pieces of clinical information: the patient’s disease activity (such as joint swelling, pain, etc.) and the level of inflammation seen in the tissue.

Their analysis revealed that the total white blood cell count in the synovial fluid did not correlate with disease activity, however, the counting of individual cell types gave insights into tissue inflammation. As such, a higher percentage of neutrophils was associated with increased inflammation in the tissue, while a higher percentage of monocytes was associated with lower inflammation in the tissue.

Because the white blood cell counts in synovial fluid provided distinct and different information from standard disease activity measures and correlated well with tissue inflammation, the team believes it could help guide the selection of personalized anti-inflammatory therapies more efficiently.

“Synovial fluid extraction is already a routine part of care, but until now, it has never been used to analyze disease state in this way,” explained Dr. Goodman. In other words, the approach could be adopted without placing additional burden on healthcare providers.

"It's important that we're gaining new methods of investigating patients with RA,” Dr. Goodman added, “since choosing the appropriate therapy and choosing it in an efficient way is clearly the best way to achieve the best outcomes.”

According to Dr. Goodman, the next phase of this study, led by HSS rheumatologists Melanie H. Smith, MD, MPH, and Dana Orange, MD, MS, will look at both the proteomics and genetics of the cells within the fluid with more molecular and immunologic techniques, with the goal of finding even more clinically relevant and important information.

Poster details

Title: Can synovial fluid features be used to predict synovial tissue pathotype?

Authors: Susan M. Goodman, Michael Parides, Solana Cushing, Daniel Ramirez, Edward DiCarlo, Rebecca B. Blank, Laura Donlin, Anna Helena Jonsson, Amit Lakhanpal, Bella Mehta, Dana Orange, Melanie Smith.

Abstract n°: 2057

Presentation: June 12^th, 2025. 2:45 PM CEST

“These findings give some reassurance to female patients that there are physiological reasons why they are having more pain,” says Bella Mehta, MBBS, MS, rheumatologist at HSS and lead author of the study. “Our work may also help us develop better therapies, especially for women with more severe symptoms.”

The study enrolled 135 patients with knee OA who were scheduled to have total knee replacement. A total of 82 participants were female. Researchers analyzed patient-reported symptoms of pain, histology (tissue samples removed during surgery and examined under the microscope) and genetic markers of inflammation in the blood.

The study found that women with knee OA had higher markers of inflammation in their blood, increased tissue inflammation and widespread cartilage loss. This corresponds with the study’s findings that women reported higher levels of pain, even at night when at rest.

The findings also revealed specific genetic expression patterns in women that notably increased synovial tissue inflammation. This occurs when the synovium, the thin layer of tissue above the cartilage that helps lubricate the knee joint, becomes inflamed and painful.

“Traditionally, it was thought that knee osteoarthritis was caused by years of significant wear and tear on the cartilage in the knee joint, but synovial inflammation is now known to play a big role in this condition,” notes Dr. Mehta.

Knee osteoarthritis is the most common type of arthritis in the world. Most people over the age of 65 have some form of it, with around 70% to 80% experiencing symptoms of pain and stiffness.

Pain is typically reported more frequently in women with knee OA than in men. Dr. Mehta suggests several theories as to why, including:

-Mechanical differences between men and women. A woman’s pelvis or hip bone is shaped differently than men so they can accommodate having babies. This has implications on the knee joint, which may increase osteoarthritis and pain.

-Hormonal differences in estrogen and progesterone after menopause, which may make women more prone to osteoarthritis.

-Differences in genetics. Women are born with two X chromosomes, whereas men have an X and a Y chromosome. The second X chromosome expresses certain genes that increase the likelihood for women to have osteoarthritis.

“It’s not that women complain of more pain. There are objective, physiological differences that we have seen between men and women that can explain this,” says Dr. Mehta. “For example, they have increased markers of inflammation in their blood, inflammatory gene expression and more mechanical stress and cartilage loss in the knee, all contributing to more pain even at rest.”

Currently, first-line treatments for people with knee OA include medications to manage pain, and exercise to strengthen the muscles and ligaments around the knees. However, if there is no improvement, surgery is recommended.

Researchers continue to look for ways to improve treatment options for knee OA. “There may be certain immunomodulatory agents that target the genetic mechanisms driving tissue inflammation in women, but more research is needed to better understand these genes and their role in accelerating knee osteoarthritis in females,” says Dr. Mehta.