Hospital for Special Surgery shares new research highlighting improved recovery, safety, and long-term outcomes through optimized perioperative medication strategies in hip and knee replacement patients.
Hospital for Special Surgery (HSS), widely recognized as the world’s leading academic medical center dedicated to musculoskeletal health, has announced the results of several major studies evaluating targeted medication strategies in joint replacement surgery. The findings, presented at the annual meeting of the American Academy of Orthopaedic Surgeons (AAOS), shed new light on perioperative medication management — a critical yet often debated component of hip and knee arthroplasty care.
Perioperative medication decisions directly influence surgical recovery, complication rates, pain control, and long-term outcomes. Through three large-scale investigations, HSS researchers examined how blood thinners, anti-inflammatory medications, and antibiotic protocols affect patients undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA). Collectively, the data challenge long-held assumptions about medication risks and suggest that carefully selected targeted therapies can improve safety, reduce postoperative discomfort, and enhance recovery.
Aspirin Versus Potent Anticoagulants in Total Knee Arthroplasty
The first study, titled “Aspirin Versus Potent VTE Chemoprophylaxis in Total Knee Arthroplasty: Reduced Postoperative Pain and Complications with Aspirin Use,” explored outcomes among TKA patients who required venous thromboembolism (VTE) prevention following surgery.
Blood clot prevention is a standard component of postoperative care after joint replacement. Traditionally, many surgeons have relied on potent anticoagulants to reduce clot risk. However, questions remain about whether stronger agents may inadvertently worsen inflammation, swelling, or postoperative pain.
To investigate this issue, researchers analyzed data from 28,169 total knee replacement patients treated between 2016 and 2023. Among them, 18,413 received aspirin as their VTE prophylaxis, while 9,756 were treated with more potent anticoagulants. All patients were monitored for 90 days following surgery.
The results were striking. Patients receiving aspirin experienced less postoperative pain and fewer complications compared to those on stronger anticoagulation regimens. The data suggest that aspirin may offer an optimal balance between clot prevention and inflammation control in many TKA patients.
Brian P. Chalmers, MD, hip and knee surgeon at HSS and one of the study’s authors, noted that conventional wisdom has long discouraged the use of non-steroidal anti-inflammatory drugs (NSAIDs) in patients receiving anticoagulation therapy. The concern has been that combining these medications could increase bleeding risk. However, the study’s findings indicate that patients utilizing aspirin — which has both antiplatelet and mild anti-inflammatory properties — experienced reduced swelling and discomfort without added complications.
The findings support a shift in clinical thinking: for appropriate TKA patients, aspirin may be the preferred first-line option for VTE prevention while simultaneously improving the postoperative recovery experience.
NSAIDs and Anticoagulation in Total Hip Arthroplasty
The second study, “The Effect of Concomitant Use of Potent Anticoagulation and Anti-Inflammatories on Early Outcomes of Total Hip Arthroplasty,” focused on a related but distinct question: Can patients safely receive NSAIDs alongside anticoagulation after total hip replacement?
Historically, surgeons have been cautious about prescribing NSAIDs to patients already taking anticoagulants. The prevailing belief has been that combining the two could increase bleeding complications, wound issues, or other adverse outcomes.
To evaluate this concern, HSS researchers conducted a retrospective analysis of 5,881 total hip arthroplasty patients who were receiving anticoagulation therapy between 2016 and 2023. Of these patients, 4,867 were also prescribed NSAIDs, while 1,040 received anticoagulation alone.
Contrary to traditional assumptions, the study found no increased risk of wound-related bleeding complications among patients taking both NSAIDs and anticoagulants. In fact, those receiving combination therapy demonstrated meaningful clinical benefits, including improved pain control and an easier early recovery period.
Dr. Chalmers emphasized that while caution is always warranted in medication management, real-world data did not show the anticipated rise in complications. Instead, NSAIDs appeared safe in this setting and may play a valuable role in reducing postoperative pain and decreasing reliance on opioid medications — an especially important consideration amid ongoing concerns about opioid overuse.
The findings suggest that carefully managed concomitant therapy may provide a pathway toward more comfortable and efficient recovery following hip replacement surgery.
Cefazolin Safety in Patients with Cephalosporin Allergy
The third study addressed a different but equally significant question: Can patients with documented cephalosporin allergies safely receive cefazolin, the standard antibiotic prophylaxis for joint replacement surgery?
The study, “Cefazolin and the R-1 Side Chain: Why Your Joint Arthroplasty Patients With Cephalosporin Allergy Can Safely Be Given Cefazolin,” is the first large-scale investigation to directly evaluate this issue in arthroplasty patients.
Antibiotic prophylaxis is essential in joint replacement procedures to prevent surgical site infections, which can have devastating consequences. Cefazolin is widely regarded as the most effective first-line antibiotic for this purpose. However, when patients report a cephalosporin allergy, clinicians often substitute alternative antibiotics that may not be as effective.
HSS researchers analyzed data from 89,993 hip and knee arthroplasty patients treated between 2016 and 2024. Among them, 1,267 patients had documented cephalosporin allergies. The study compared outcomes between allergic patients who received perioperative cefazolin and those who received alternative antibiotic regimens.
The results were reassuring. There were zero incidences of IgE-mediated or severe type IV allergic reactions among patients with reported cephalosporin allergies who were given cefazolin. These findings strongly suggest that cefazolin can be safely administered to most patients with mild or historical cephalosporin allergies.
Matthew S. Austin, MD, hip and knee surgeon at HSS and co-author of the study, emphasized the importance of standardized allergy assessment protocols. Mild past reactions often prompt automatic substitution with broader-spectrum antibiotics, yet alternatives may not provide the same level of infection prevention. Clear guidelines, he noted, can help clinicians make evidence-based decisions that maximize safety and effectiveness.
Advancing Data-Driven Perioperative Care
Together, the three studies underscore HSS’s commitment to challenging entrenched assumptions and refining perioperative care through rigorous, data-driven research. Each investigation addressed areas where longstanding clinical habits may not have fully aligned with contemporary evidence.
The collective findings suggest that:
- Aspirin may offer superior postoperative comfort compared to more potent anticoagulants in total knee arthroplasty.
- NSAIDs can be safely used alongside anticoagulation in total hip arthroplasty without increasing bleeding risk.
- Cefazolin remains a safe and highly effective prophylactic antibiotic for most patients with reported cephalosporin allergies.
By reexamining traditional medication strategies, HSS researchers aim to optimize patient outcomes, minimize complications, and improve recovery experiences for the growing number of individuals undergoing hip and knee replacement surgery.
As joint arthroplasty procedures continue to rise globally, these insights provide valuable guidance for orthopedic surgeons, anesthesiologists, and perioperative care teams seeking to deliver safer, more effective, and patient-centered care.
Through ongoing research, innovation, and education, Hospital for Special Surgery continues to lead the advancement of musculoskeletal medicine — ensuring that treatment decisions are guided not by assumption, but by evidence.