Spinal stenosis may occur due to cartilage destruction. This may cause pressure on the spinal cord and nerve roots. The resulting pain and weakness may lead to problems with movement anywhere below the area of damage. So people may have pain in their legs and feet when walking or even when resting in bed, which can be very disabling. Although spinal stenosis primarily develops due to OA, the neck involvement of RA may also cause it.
Osteoporosis is a thinning of bone that can lead to fractures.
In addition to the impact of RA in increasing osteoporosis, people with RA have the same osteoporosis risks as the rest of the population as we age. Women are at special risk due to a decline in estrogen after menopause. Decreased weight bearing due to inadequate exercise also contributes to osteoporosis. So if you can't bear weight and aren't walking enough due to RA, you have a further accelerated osteoporosis risk. Muscle strength often declines with aging, and factors related to RA, OA, and osteoporosis can make it worse.