Table 1_Impact of stair climbing volume on patellofemoral cartilage: a dose-response analysis from the osteoarthritis initiative reveals elevated risk at middle levels.docx

ObjectiveTo evaluate the impact of stair climbing volume on cartilage degeneration in the patellofemoral joint, with a particular focus on the medial/lateral patellar and trochlear regions.
MethodsUtilizing data from the osteoarthritis initiative (OAI) cohort, we analyzed 581 participants with baseline and 24-month follow-up MRI assessments. Cartilage damage was evaluated using the MRI Osteoarthritis Knee Score (MOAKS), with subregional stratification (medial/lateral patella, medial/lateral trochlea). Stair-climbing volume was categorized as low (0–4 flights/week), middle (5–6 flights/week), or high (> 6 flights/week). Logistic regression models adjusted for BMI, age, and sex assessed the dose-response relationship between stair climbing and cartilage deterioration across patellofemoral subregions.
ResultsA total of 581 participants were included (59.4% female, age 61.6 ± 8.9 years, BMI = 30.7 ± 4.7 kg/m2); 13.6, 6.4, and 80% of the participants reported stair climbing of 0–4, 5–6, and > 6 flights per week, respectively. Middle-volume stair climbing was associated with an increased risk of worsening MOAKS cartilage score [adjusted OR (95% CI): 3.068 (1.230–7.652)]. Stratified analysis showed that middle-volume stair climbing was associated with worsening MOAKS cartilage score of trochlear surface cartilage [adjusted OR (95% CI): 4.495 (1.148–17.592)].
ConclusionMiddle-volume stair climbing was associated with greater progression of patellofemoral joint cartilage deterioration, particularly in the trochlear region, suggesting that mechanical loading patterns during stair climbing may influence subregional cartilage vulnerability.