- StandProud/ACDF PROJECT - DISABILITY TYPES - WHO WE ARE Polio
paralyzes motor nerves (most commonly those of the legs, but
also frequently of the back and sometimes of the arms). The
muscles which the paralyzed nerves are supposed to control do
not get sufficient exercise and thus begin to atrophy soon after
the patient has recovered from the active phase of the disease.
When, as is often the case, the muscles atrophy unevenly on the
two opposing sides of a joint, it is called "muscle imbalance"
and, if left uncorrected, usually results in the joint coming to
favor strongly a particular position (the stronger muscle
pulling harder than the more paralyzed one). For example, often
in polio cases, the muscles in the back of the thigh are less
paralyzed and retain more strength (atrophy less) than the
muscles toward the front of the thigh. Since the back thigh
muscles which pull the leg back into a bent position meet little
resistance from the front thigh muscles (used to pull the lower
leg forward into the str