Knee osteoarthritis is one of the most common causes of
chronic pain worldwide, and several animal models have been developed to investigate disease mechanisms and treatments to combat associated morbidities. Here we describe a novel method for assessment of locomotor
pain behavior in Yucatan swine. We used
monosodium iodoacetate (MIA) to induce
osteoarthritis in the hindlimb knee, and then conducted live observation, quantitative gait analysis, and quantitative weight-bearing stance analysis. We used these methods to test the hypothesis that locomotor
pain behaviors after
osteoarthritis induction would be detected by multiparameter quantitation for at least 12 wk in a novel large animal model of
osteoarthritis. MIA-induced
knee osteoarthritis produced lameness quantifiable by all measurement techniques, with onset at 2 to 4 wk and persistence until the conclusion of the study at 12 wk. Both live observation and gait analysis of kinetic parameters identified mild and moderate
osteoarthritis phenotypes corresponding to a binary dose relationship. Quantitative stance analysis demonstrated the greatest sensitivity, discriminating between mild
osteoarthritis states induced by 1.2 and 4.0 mg MIA, with stability of expression for as long as 12 wk. The multiparameter quantitation used in our study allowed rejection of the null hypothesis. This large animal model of quantitative locomotor
pain resulting from MIA-induced
osteoarthritis may support the assessment of new
analgesic strategies for human
knee osteoarthritis.