Ultrasound reference values for trochlear cartilage in healthy black African subjects: a study of a cohort of 506 participants

Objective To establish ultrasound reference values for femoral trochlear cartilage thickness in healthy adults of Black African origin and identify factors influencing variation. Methods Cross-sectional study conducted at Bogodogo University Hospital (Burkina Faso) on 506 healthy participants (1,012 knees) aged 18 to 45 years. Thickness was measured by a single radiologist using an ultrasound scanner with a high-frequency linear probe (8–15 MHz) at the medial condyle (MC), lateral condyle (LC), and intercondylar zone (ICZ). Multiple linear regression was used to analyze the factors associated with variations in thickness. Results The population consisted of 408 men (80.63%) and 98 women (19.37%) with a mean age of 24.36 ± 3.42 years. The mean thickness was 2.36 mm at the MC, 2.38 mm at the LC, and 2.60 mm at the ICA. Bivariate analysis showed significantly thicker cartilage in men (p = 0.001). After multivariate adjustment, gender and weight remained positively associated with thickness (p < 0.001), while BMI showed a negative association. Age was no longer significantly associated in the final model. Conclusion This study provides the first ultrasound standards for trochlear cartilage in a sub-Saharan African population. These data constitute an essential paraclinical reference for the early detection of knee osteoarthritis and the interpretation of cartilage measurements in this geographical context.