Altered Knee Biomechanics Linked to Worsened Knee Pain and Cartilage Damage in Osteoarthritis

A new study has identified specific gait biomechanical characteristics associated with pain and cartilage damage in individuals with patellofemoral joint osteoarthritis during a stair descent activity. Researchers at the University of California San Francisco (UCSF) conducted a cross-sectional observational study involving 83 participants, 66 of whom completed all components required for the analysis. The study found significant associations between biomechanical characteristics and patient-reported outcomes from the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire and Whole Organ MRI Score (WORMS) gradings to assess severity of cartilage abnormalities.

Key Takeaways:

  • The study identified knee joint kinematics and kinetics during stair descent as key predictors of pain and cartilage damage in individuals with patellofemoral joint osteoarthritis.
  • The research revealed significant associations between biomechanical characteristics and patient-reported outcomes from the KOOS questionnaire, including pain, symptoms, and patellofemoral function.
  • The study found that greater knee flexion at late stance was linked to worse KOOS scores in both the whole cohort and male participants.
  • The research also uncovered sex-specific differences in the associations between biomechanical characteristics and cartilage damage, emphasizing the need for individualized interventions to address movement abnormalities.
  • The study was supported by the National Institutes of Health and the National Institute of Arthritis and Musculoskeletal and Skin Diseases.
  • The research was conducted in collaboration with a university-based motion analysis laboratory and musculoskeletal imaging center.

Statistics:

  • 83 participants were recruited for the study, with 66 completing all components required for the analysis.
  • The study found significant associations between biomechanical characteristics and KOOS scores (pain, symptoms, and patellofemoral function) in 71, 83, and 73% of participants, respectively.
  • Significant associations were also found between biomechanical characteristics and WORMS gradings to assess severity of cartilage abnormalities in 85% of participants.
  • The study revealed sex-specific differences in the associations between biomechanical characteristics and cartilage damage, with significant associations found in 67% of male participants and 85% of female participants.
  • The research was published in the BMJ Open journal on October 15, 2025.

Sources:

  • NewsRx. University of California San Francisco (UCSF) Researchers Report Research in Osteoarthritis (Predictors of pain and cartilage damage in patellofemoral joint osteoarthritis: stair descent knee kinematics and kinetics). Health & Medicine Week. October 31, 2025; p 8443.
  • BMJ Open. Predictors of pain and cartilage damage in patellofemoral joint osteoarthritis: stair descent knee kinematics and kinetics. 2025,15(10). (BMJ Open - http://bmjopen.bmj.com/)
  • University of California San Francisco (UCSF). Department of Epidemiology and Biostatistics.