Can a cane dependent person use a cane on Shabbat to walk to synagogue?
Walking outside with a cane for an old man or the use crutches for one who hurt his foot will depend on how much one must rely on the cane or crutches. If the person cannot walk without them then the cane or crutch is considered like the person foot and it may be used outdoors on shabbos. However if one manages without them, such as to get around his house, then he may not use them outside. Therefore an elderly man that only uses his cane outside the house when he is walking long distances may not use his cane in the street on shabbos, (unless there is a Eruv).
O:CH 301- 15-18 M:B ibid 64.