Gait analysis in a rat model of osteoarthrosis

Gait analysis has been undertaken in a rat model of osteoarthrosis, induced by intra-articular injection of sodium iodoacetate into the left knee. Two weeks after injection, no disturbances were recorded to the velocity of locomotion, the stride length nor the stride, stance, or swing times. However, clear and consistent reductions in the peak vertical load bearing (Pz) by the affected limb were observed of 22-29% relative to the other limbs, with the right forelimb taking the major share of extra load. This redistribution fitted well with the gait pattern of the rat, allowing Pz redistribution with minimum gait disturbance, and was still present 6 weeks later. These results are discussed in the context of the possible load sensitivity of the damage process to the gait pattern of the rat.