Johnston v. R., 98 DTC 6169, [1998] 2 C.T.C. 262 (FCA) -- summary under Subsection 118.4(1)

The taxpayer, who suffered from spinal epiphyseal dysplasia was found to have a markedly restricted ability to walk given that even on his best days, he could walk only short distances of 50 feet (which took him five minutes). He also had a marked restriction in his ability to feed and dress himself that, given that he could not prepare food generally (let alone food that was medically required by his state of health) and that before dressing himself, had to exercise up to 20 minutes because his limbs were numb.