Advancements in surgical techniques and the increased use of a medication called tranexamic acid for preventing and controlling bleeding have made it possible for many patients undergoing knee replacement to avoid needing a transfusion, which requires hospital admission for at least a day.

Despite these advancements, it was believed that patients with RA undergoing orthopedic surgeries had an elevated risk of transfusion since they tend to have higher rates of anemia compared to the individuals without the disease. RA occurs in about 1% of the general American population.² About 4% of patients having joint replacement surgeries at HSS have the disease.

“Learning that rheumatoid arthritis was not a transfusion risk factor was unexpected,” said HSS rheumatologist Susan M. Goodman, MD, co-author of the study. “However, we believe presurgical care, including proactively managing chronic anemia before surgery, played a key role in minimizing transfusion risk.”

For their study, Dr. Goodman, HSS rheumatologist Linda A. Russell, MD, and colleagues analyzed hospital records for more than 29,000 patients who had a single total knee arthroplasty procedure at HSS from February 2016 to December 2022. A total of 822 patients, or 2.8%, received transfusions. The transfusion rate declined significantly during the study period from 5.7% in 2016 to 0.9% in 2022.

The investigators reviewed patient demographics such as age and sex, preoperative hemoglobin levels, RA diagnosis and the use of tranexamic acid during surgery, and then looked for associations with transfusion risk.

“In addition to finding that rheumatoid arthritis was not a transfusion risk factor, analysis revealed that a higher preoperative hemoglobin level and the use of tranexamic acid significantly decreased transfusion risk, while being male and having a greater burden of other diseases increased risk,” said HSS pre-doctoral student and research assistant Stephen Batter, BA, the presenting author of the poster summarizing the study.

The research team plans to use their unexpected findings to develop a tool to identify patients with different levels of transfusion risk based on preoperative hemoglobin level, sex, age and health status. This initiative may help orthopedic surgeons better anticipate which patients can safely avoid transfusion and may be suitable candidates for outpatient knee replacement surgery.

Authors: Stephen Batter, BA, Huong Do, MA, Dongmei Sun, PhD, Ahmed Deeb, BA, Trang Bui, MD, Jason L. Blevins, MD, Mark P. Figgie, MD, Gwo-Chin Lee, MD, J. Alex B. Gibbons, BA, Bella Mehta, MD, MS, MBBS, Susan M. Goodman, MD, Linda Russell, MD.

Reference:

¹ Batter S, Do H, Sun D, Deeb A, Bui T, Blevins J, Figgie M, Lee G, Gibbons J, Mehta B, Goodman S, A Russell L. Investigating Predictors of Transfusion in Rheumatoid Arthritis and Osteoarthritis Patients Undergoing Knee Arthroplasty [abstract]. Arthritis Rheumatol. 2024; 76 (suppl 9). https://acrabstracts.org/abstract/investigating-predictors-of-transfusion-in-rheumatoid-arthritis-and-osteoarthritis-patients-undergoing-knee-arthroplasty/. Accessed October 10, 2024.

² Xu Y, Wu Q. Prevalence Trend and Disparities in Rheumatoid Arthritis among US Adults, 2005-2018. J Clin Med. 2021;10(15):3289. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8348893/. Accessed October 10, 2024.

Researchers at HSS and other institutions have noted that women with knee osteoarthritis report more pain than men, but the reason for this difference has been unclear. “Others have speculated that women tend to delay surgery more than men, but when we looked in our database, that wasn’t true,” said HSS rheumatologist Dana Orange, MD, MS, assistant professor at The Rockefeller University and senior author of the study. “We studied synovial tissue removed at the time of total knee arthroplasty to look for a biological reason that may explain the difference in reported pain between sexes.”  

Synovial tissue lines the knee joint and produces fluid that helps the joint move. It can become inflamed as osteoarthritis progresses. Pathologists at HSS have been generating data on different types of cells found in synovial tissue, including mast cells, which are also found in many other tissues throughout the body and are commonly known for producing inflammatory chemicals called histamines during allergic reactions and asthma. Basic research by other scientists has suggested a link between mast cells and osteoarthritis progression and pain.

Dr. Orange and colleagues, including HSS rheumatologist Bella Mehta, MBBS, MS, lead author of the study, studied joint tissue obtained from 96 women and 61 men who underwent total knee replacement at HSS. They counted the number of cells for more than a dozen cell types typically found in synovial tissue and examined synovial fluid and blood using a high-powered microscope. They also evaluated patient-reported pain outcomes collected with two validated surveys. “At HSS, we were in a unique position to conduct this research because we have synovial tissues collected from patients with end-stage osteoarthritis undergoing arthroplasty and expert musculoskeletal pathologists who systematically grade tissue samples for 13 characteristics,” Dr. Mehta said.  

The investigators discovered that synovial tissue from women had significantly more mast cells, 63 per sample area, compared to 46 in tissue from men, on average. They also found higher levels of a byproduct of mast cells called tryptase in synovial tissue from women than men, providing further evidence of increased mast cell activity. No other differences in synovial tissue between sexes were observed. Finally, as expected, women reported worse pain than men on both surveys.

“We hope our findings encourage other researchers to start thinking about biological factors that may contribute to sex differences in patient-reported pain in knee osteoarthritis,” Dr. Orange said.

Authors: Bella Mehta, MBBS, MS, Edward F. Dicarlo, MD, Miguel Otero, PhD, Peter K. Sculco, MD, Mark P. Figgie, MD, Susan M. Goodman, MD (HSS), Fei Wang, PhD (Weill Cornell Medicine), Eun Kyung Song, PhD (Stanford University School of Medicine), Dana Orange, MD, MS (HSS and The Rockefeller University). 

TKR is often the only management option for patients with severe knee joint damage. Identifying which disease caused the joint damage is essential for guiding treatment plans, given that RA is a systemic, inflammatory disease that may also affect the eyes or lining around the heart, while OA affects just the joints. “We know there are many more immune cells present in the synovium, or joint tissue, of patients with RA compared to those with OA,” said Bella Mehta, MBBS, MS, rheumatologist at HSS and lead author of the study. “But precisely how many more has not been clear.”

“Pathologists typically assess images of synovium to determine the extent of inflammation using a combination of approaches, including assigning the level of immune cell infiltration on a scale from 0 to 4,” said Dana Orange, MD, MS, rheumatologist at HSS, assistant professor at Rockefeller University and senior author of the study. “However, these methods are imperfect.” For example, a recent study by HSS investigators found that assessments from two highly experienced pathologists evaluating the infiltration of one type of immune cells known as lymphocytes on the same slides agreed only 67 percent of the time.¹

Drs. Orange, Mehta and colleagues at HSS and collaborating institutions developed and validated a computer vision tool that rapidly counts tens of thousands of cell nuclei in whole-slide images of synovium.² For their present study, they measured 14 different pathologist-scored features in synovium from 60 patients with RA and 147 patients with OA who underwent TKR, and used the computer vision tool to determine cell density.

The investigators identified significant differences between RA and OA features in synovium. The RA samples showed increased cell density; low numbers of mast cells, a type of white blood cell; and lower evidence of fibrosis or scarring compared to the OA samples. The probability of correctly distinguishing between RA and OA in synovium was 85 percent when using the 14 pathologist-scored features alone, 88 percent when using the computer’s score for cell density alone and 91 percent when the researchers combined the pathologists’ scores and the computer’s cell density calculation. The researchers determined a cutoff point for distinguishing RA from OA, determining that synovium containing more than 3,400 cells per mm² should be classified as RA.

“While our innovation is not ready for clinical use yet, it holds promise for assisting pathologists in the future,” Dr. Orange said. “Right now, we see it as a valuable tool for research purposes because it provides an accurate and 100% reproducible score of inflammation and look forward to developing it further.”

Dr. Orange added that in the future computer vision could be trained to glean other types of information from tissue samples, including which types of cells are present and whether they are close enough together that they are likely to be communicating with each other. This more granular assessment might enable clinicians to know more precisely which cells are causing tissue damage and tailor treatments accordingly.

Authors: Bella Mehta, MBBS, MS, Susan M. Goodman, MD, Edward F. DiCarlo, MD, Deanna Jannat-Khah, J. Alex Gibbons, Miguel Otero, PhD, Laura Donlin, PhD (HSS), Tania Pannellini, MD, PhD (Weill Cornell Medicine), William Robinson, MD, PhD (Stanford University), Peter K. Sculco, MD, Mark P. Figgie, MD, Jose A. Rodriguez, MD (HSS), Jessica Kirschmann (Stanford University), James Thompson, David Slater, Damon Frezza (The MITRE Corporation), Zhenxing Xu, Fei Wang, PhD (Weill Cornell Medicine), Dana Orange, MD, MS (HSS and Rockefeller University).

References

1. Orange DE, Agius P, DiCarlo EF, et al. Identification of Three Rheumatoid Arthritis Disease Subtypes by Machine Learning Integration of Synovial Histologic Features and RNA Sequencing Data. Arthritis Rheumatol. 2018;70(5):690-701. doi:10.1002/art.40428

2. Guan S, Mehta B, Slater D, et al. Rheumatoid Arthritis Synovial Inflammation Quantification Using Computer Vision. ACR Open Rheumatol. 2022;4(4):322-331. doi:10.1002/acr2.11381

“Patient satisfaction related to the hospital experience following surgery is an important aspect of patient care,” said Susan M. Goodman, MD, a rheumatologist at Hospital for Special Surgery (HSS) and senior investigator. “The Press Ganey inpatient survey is commonly administered to patients to assess their satisfaction with the process of care. Our aim was to determine whether overall patient assessment scores differed by race or socioeconomic status.”

Dr. Goodman and a team of researchers reviewed the Press Ganey survey responses of more than 4,600 patients who had surgery at HSS from July 2010 to February 2012. Individuals having a primary knee or hip replacement who resided in New York, New Jersey or Connecticut were included in the study.

Researchers analyzed the data to establish an overall score, calculated as the mean of a patient’s ratings for three questions in the “Overall Assessment” section of the Press Ganey survey. The results were categorized as either “completely satisfied” (score of 100) or “not completely satisfied” (score <100).

The analysis, which included 2,516 individuals who underwent hip replacement and 2,113 who had a knee replacement, found that Black patients were more likely to indicate they were “not completely satisfied” compared to white patients in both joint replacement groups.

Dr. Goodman said that although Black patients indicated they were less satisfied with the process of care right after surgery, there was no difference in satisfaction with their joint replacement outcome. Factors such as pain and function are part of the outcome assessment, which is generally conducted two years after surgery.  

With respect to socioeconomic status, researchers considered the patient’s primary health insurance coverage. The study found that the individual’s primary payor was not associated with satisfaction in either joint replacement group.

“The study is important because we know that Black patients generally wait longer to seek treatment, presenting with worse pain and function prior to surgery, and we are trying to sort out the barriers to seeking timely care,” said Mark P. Figgie, MD, chief emeritus of the Surgical Arthritis Service at HSS and co-author of the study.

“Patient outcome measures indicate that although Black patients achieve significant improvement after surgery, it does not reach the same level as those who seek timely treatment,” he added. “Confidence in the health care system may contribute to the delay in seeking care, and this is something we need to address.”

Dr. Goodman added, “More research is needed to investigate other factors, such as perceived staff courtesy and baseline pain and function, to understand why disparities exist so we can achieve a high level of patient satisfaction for everyone.”

Authors: Anne R. Bass, MD, Emily Ying LAI, MSc, Huong Do, MA (HSS), John A. Gibbons, BA, Letitia Bradford, MD, FAAOS, FACS (Nth Dimensions), Mark P. Figgie, MD, Michael L. Parks, MD (HSS), Orett Burke, BS (Rutgers Robert Wood Johnson Medical School), Susan M. Goodman, MD (HSS).

Between 2000 and 2016, the number of total hip arthroplasty (THA) procedures performed in patients under 21 years of age increased from 347 to 551, while the total pediatric population in the United States remained stable, the researchers found.

Traditionally, most young patients undergoing THA suffer from developmental bone or joint ailments or juvenile inflammatory arthritis. However, the new study revealed that the upswing in THA procedures in young patients is not being driven by a rise in the number of children with inflammatory joint disease, suggesting that nonsurgical therapies to control these conditions are working, said Bella Mehta, MBBS, MS, MD, a rheumatologist at HSS and the senior author of the study.

“Our study shows that although THA procedures are increasingly being performed in young people, we aren’t seeing more of these patients seeking surgery for inflammatory arthritis,” Dr. Mehta said. “We’re doing a better job at treating these individuals so they don’t develop end-stage joint damage. Twenty years ago, we didn’t have access to effective pharmacologic treatments for these conditions, and now we’re using them well and helping these patients live a better life.”

“These procedures are still pretty rare in hospitals, and some surgeons might not see any young patients,” added Alex Gibbons, a research assistant in Dr. Mehta’s group and a co-author of the study. “Although some site-specific data on THAs in adolescents exist, it wasn’t known how frequently these procedures were being performed in the United States and if that frequency was growing or not.”

For the study, Dr. Mehta and her colleagues used the Kids’ Inpatient Database, a repository of information on patients under 21 years of age from approximately 4,200 hospitals in 46 states. The researchers looked for elective and non-elective primary THA procedures.

The mean age of young patients undergoing THA was just over 17 years and remained constant throughout the duration of the study. Most patients were white (55.3%) and had private insurance (56.5%). The majority (80%) of THAs were performed in urban teaching hospitals.

Mark P. Figgie, MD, chief emeritus of the Surgical Arthritis Service at HSS and a co-author of the study, said the finding that most THA procedures in young patients are performed in urban and teaching hospitals reflects a trend that is beneficial for these patients. As other studies have demonstrated in conditions like inflammatory arthritis, when hip replacements are performed by surgeons with significant experience, patients have better outcomes. “And for younger patients, the nuances require the expertise and knowledge to avoid complications and optimize outcomes,” Dr. Figgie said.

The most common diagnoses for young patients undergoing THA were osteonecrosis, osteoarthritis and juvenile idiopathic arthritis (JIA)/inflammatory arthritis, the researchers found. Over the course of the study, the frequency of THA for osteonecrosis rose from 24% to 38%, while that for arthritis fell from 27% to 4%—likely a reflection of recent improvements in medical management for the condition, they added.

Dr. Figgie noted that improvements in implant technology and materials have made the devices far more durable than they were 20 years ago. As a result, surgeons now feel more comfortable offering THA to young patients because their implants are likely to withstand the wear and tear of decades of activity.

Dr. Mehta said the findings could be of value both to clinicians and young patients, for whom, in many cases, the surgery is their first major operation. “I would use these results to say to a young person: ‘There are a lot of people who get these procedures; you’re not alone.’ I find that, especially for young patients, knowing they’re not the only ones to experience something really helps. And it’s a life-changing procedure for them.”

Now, in a new study published in Arthritis Care & Research that looked at the risk of total knee replacement revision or failure, HSS investigators found very a different result. “There was a trend toward race being a risk factor, but it was not statistically significant, and poverty had no impact: There wasn’t even a trend,” said lead study author Anne R. Bass, MD, an attending physician and program director of the Rheumatology Fellowship Program at Hospital for Special Surgery, and a professor of clinical medicine at Weill Cornell Medicine. “We were definitely surprised by our results.”

For about 85 percent to 90 percent of people who have total knee replacements, the artificial joints last about 15 to 20 years. In elderly patients, that may mean the rest of their lives. But for younger patients, especially those who are very active, the implants may fail over time and require revision. Over the last five years or so, the team of HSS researchers have been collaborating to understand the factors placing some patients at higher risk of poor outcomes, including needing revisions.

This study was the first to link patient data to a statewide discharge database. The researchers linked the HSS Knee Replacement Registry with the Statewide Planning and Research Cooperative System (SPARCS) database and captured discharge information for patients who received revisions at other hospitals within the state of New York. Also new with this study, they explored whether race and poverty played a role in knee replacement failure, a broader outcome definition that includes patients who failed to improve at all after their initial procedures but who did not have revisions. Poverty information was collected from the U.S. census data.

Among a total of 4,062 patients who had a total knee replacement between January 2008 and February 2012 at HSS, only 122 or 3 percent required revisions during a median of five years of follow-up. Black patients had a 1.7 times higher risk of knee replacement revision than white patients, but when the researchers analyzed multiple variables, race and poverty were not driving factors. Race and poverty also did not explain differences among patients with knee replacement failure.

The factors that were associated with a higher risk for revision were younger age, being male, and the use of a constrained prosthesis—a knee implant with conforming components that provides more stability. The risk factors driving failure included being treated by a surgeon that performs a low number of knee replacement surgeries and patients’ low expectations for improvement after surgery.

“Younger people and males are typically more active, putting more strain on their implants. Constrained prostheses are only used in patients with bigger deformities and ligament imbalances, which tend to put more strain on the implant and loosen the bone-cement interface,” said study author Mark P. Figgie, MD, an attending orthopedic surgeon and Chief Emeritus of the Surgical Arthritis Service at HSS, and professor of clinical orthopedic surgery at Weill Cornell Medicine. “Our findings suggest that all patients should seek care from experienced surgeons at a high-volume hospital.”

To explore their findings on a larger scale, the research team is conducting a new study, linking data from about one million patients from California, New York, Florida, Arizona, and Arkansas with their respective statewide databases. “We are asking the same questions about race and poverty, and we will be able to look at the influence of hospital choice on the risk of revision by linking to the American Hospital Association database,” Dr. Bass said. “We are also looking at differences in revisions caused by infections versus mechanical issues.” The more extensive study is expected to be completed later this year.

The findings showed that younger patients may have higher complication rates for total knee replacements.

"The number of knee replacements we are doing in younger and younger patients keeps increasing every year and we need to let these patients know that their failure rate is potentially higher," explains Dr. Figgie.

Read the full article at Reuters.com.

According to the article, the system will be designed specifically for children with juvenile idiopathic arthritis or congenital dysplastic hip disease.

Louis A. Shapiro, president and CEO of HSS, said "HSS's clinical leadership, biomechanical engineering and innovation expertise together with Wishbone's experience developing technologies to serve pediatric patients, position us to improve the quality of life of these young patients who do not have many therapeutic options. As an inventor of these technologies, Dr. Mark Figgie, our Chief of the Surgical Arthritis Service at HSS is a leading expert in the field, who along with our biomechanical engineers have a long history in both treating and innovating for this patient population."

Read the full article at wishbonemedical.com