Relationship between tissue stress during gait in healthy volunteers and patterns of urate deposition and bone erosion in gout: a biomechanical computational modelling study

OBJECTIVES To determine whether patterns of high internal tissue stress during gait are associated with patterns of monosodium urate crystal deposition and bone erosion in gout. METHODS We compared patterns of foot von Mises stress predicted computationally during gait in volunteers of normal and high body mass index (BMI) with patterns of urate deposition in gout and asymptomatic hyperuricaemia, and bone erosion in gout using dual-energy and conventional CT data. RESULTS The highest average and peak von Mises stress during gait was observed at the third metatarsal (MT) head. Similar stress patterns were observed for high and low BMI groups. In contrast, for both urate deposition and bone erosion, the first MT head was most frequently affected, with very infrequent involvement of the third MT head. There was no clear relationship between average or peak von Mises stress patterns with patterns of urate deposition or bone erosion (-0.29>r<0.16). Addition of BMI into linear regression models did not alter the findings. CONCLUSIONS These data do not support the concept that elevated internal tissue stress during biomechanical loading plays an important role in patterns of monosodium urate crystal deposition or structural damage in gout.