Research & News

At the Athletic Injury & Rehabilitation (AIR) Labs, our research focuses on improving early detection and prevention of knee osteoarthritis (OA) after injury. While knee injuries such as anterior cruciate ligament (ACL) tears are often treated with surgery, many patients still develop OA within a decade. 

Our work aims to identify those at highest risk and develop strategies to intervene earlier. 

We emphasize three pillars:

  • Ultrasound imaging to detect early joint structure changes
  • Patient-reported outcomes to define early OA symptoms
  • Biomechanics and physical activity to understand how movement shapes long-term joint health 

Our interdisciplinary approach links kinesiology, clinical science, engineering, rehabilitation, and radiology to advance discovery and improve quality of life for patients recovering from knee injury.

We use ultrasound to gain a comprehensive view of early joint alterations in patients recovering from ACL reconstruction (ACLR). Unlike X-rays, ultrasound allows us to evaluate multiple tissues and processes that contribute to OA development. 

Our work spans:

  • Inflammation: Detecting effusion-synovitis, present in up to 87% of ACLR patients.
  • Fat pad changes: Using shear wave elastography to measure stiffness of the infrapatellar fat pad, which is linked to early OA symptoms.
  • Cartilage health: Validating ultrasound measures of cartilage composition against MRI and developing semi-automated and AI-based methods for cartilage segmentation.
  • Muscle and adiposity: Extending ultrasound applications to assess muscle quality and body composition, offering a holistic picture of OA risk.
  • Wireless ultrasound: Validating handheld wireless probes to make joint imaging more accessible, efficient, and practical in clinical and research settings. 

Ultrasound helps us look inside the knee in real time. We can see swelling, measure cartilage health, and even test how stiff tissues are. These tools allow us to spot signs of arthritis years before an X-ray can, making it possible to step in earlier with treatment.

Our research challenges the long-held assumption that symptoms after ACLR are simply part of recovery. Using both clinical studies and large national registries, we show that persistent symptoms are powerful predictors of long-term outcomes:

  • High prevalence across populations: Nearly half of patients in U.S. and New Zealand cohorts meet criteria for early OA symptoms within two years of ACL reconstruction.
  • Persistence over new onset: Symptoms are far more likely to continue over time than to develop later, highlighting a subgroup at risk of “failed recovery.”
  • Predictive utility: Patients with symptoms at one year are up to ten times more likely to report persistent symptoms at two years and are at increased risk for radiographic OA within five years. 

Many patients think knee pain after surgery is just part of recovery. But our research shows that symptoms that don’t go away are red flags. Ongoing pain or swelling often means the joint isn’t healing as expected. Recognizing these problems early can help provide the right care to prevent arthritis from taking hold.

Movement is both a reflection of recovery and a driver of joint health. We integrate motion capture, in-shoe force sensors, and wearable accelerometers to show how gait and physical activity contribute to OA risk:

  • Loading and inflammation: Abnormal gait mechanics increase stress on the knee and correlate with higher inflammation, showing how biomechanics and biology are interconnected.
  • Accessible assessment tools: Markerless motion capture, wearable accelerometers, and in-shoe force sensors bring biomechanical analysis beyond the lab, enabling real-world assessment of recovery.
  • Activity and long-term outcomes: Both how much patients move and how well they move are linked to OA risk—lower activity levels and abnormal gait predict greater inflammation and poorer recovery. 

How you move matters. After a knee injury, some people walk or run in ways that put too much stress on the joint. We use cameras, shoe sensors, and wearable trackers to identify risky patterns. This helps us design rehab strategies that retrain movement and reduce arthritis risk.

Putting it Together

Our research integrates imaging, symptoms, and movement to identify risk earlier, guide personalized rehabilitation, and ultimately prevent osteoarthritis before it becomes disabling. By combining these approaches, AIR Labs advances the science of musculoskeletal health and translates discoveries into strategies that help patients stay active and pain-free after knee injury.