Does joint alignment affect the T2 values of cartilage in patients with knee osteoarthritis?

ABSTRACT

OBJECTIVE: To assess the relationship between T2 values of femorotibial cartilage and knee alignment in patients with clinical symptoms of medial osteoarthritis (OA). METHODS: Twenty-four patients (mean age +/- standard deviation, 62.5 +/- 9.9 years) with clinical symptoms of medial knee OA, 12 with varus and 12 with valgus alignment of the femorotibial joint, were investigated on 3T MR using a 2D multi-echo spin echo (MESE) sequence for T2 mapping. Analysis of covariance, Spearman correlation coefficients, exact Mann-Whitney tests, and Fisher's exact tests were used for statistical analysis. RESULTS: Overall the T2 values of cartilage in the medial compartment (median +/- interquartile-range, 49.44 +/- 6.58) were significantly higher (P = 0.0043) than those in the lateral compartment (47.15 +/- 6.87). Patients with varus alignment (50.83 +/- 6.30 ms) had significantly higher T2 values of cartilage (P < 0.0001) than patients with valgus alignment (46.20 +/- 6.00 ms). No statistically significant association between the T2 values of cartilage (in either location) and the Kellgren Lawrence score was found in the varus or in the valgus group. CONCLUSION: T2 measurements were increased in medial knee OA patients with varus alignment, adding support to the theory of an association of OA and joint alignment.