Evaluation of joint cartilage thickness in healthy children by ultrasound: An experience from a developing nation

OBJECTIVES: Musculoskeletal ultrasound (MSUS) has a crucial role in clinical assessment and monitoring of patients with rheumatologic diseases. Early detection of joint cartilage destruction is difficult. MSUS is a cheap, noninvasive, nonhazardous bedside tool that can be used for detection of cartilage damage. We aimed to generate normative data of joint cartilage thickness of children in our population using this tool. METHODS: Healthy children, aged between 2 and 12 years, not suffering from any joint disorders and not on any chronic medication were recruited. The thickness of joint cartilage at wrist, knee and ankle were measured by ultrasound as per European League Against Rheumatism standard scan criteria. The scans were done by a single observer. RESULTS: Data of 409 children revealed median cartilage thickness at right wrist, knee and ankle joints as 2.20 (interquartile range [IQR] 1.60-3.00) mm, 2.40 (1.80-3.10) mm and 2.20 (1.80-3.00) mm, respectively. The right-left differences were not statistically significant except at the knee joint. Comparison between genders showed that boys had marginally thicker cartilage than girls at all three joints; this difference was statistically significant for the knee and ankle joints, but not at the wrist. Joint cartilage thickness showed a steady decline with age. CONCLUSIONS: Measurement of joint cartilage thickness in children with MSUS and comparison with these normative values can help in better screening for joint-related disease in children.