The choice between a cane and crutches is really a matter of comfort and stability, though your doctor may recommend one over the other depending on the physical limitations you will be battling. If you have just gone through some sort of traumatic injury that should heal within several weeks or months, a doctor is likely to recommend crutches because they are more stable and will allow you to keep weight entirely off the injured leg or foot. The main difference between a cane and crutches is the amount of weight that can be kept off the leg with each device.
While both a cane and crutches can help a person become more mobile if they have a limp or other impediment to natural movement, a cane can only provide a small amount of support. Crutches offer far more support and allow a person to keep the leg completely weight-free, but crutches are limiting because the person using them must use both hands to operate them properly. This means holding objects can be difficult, and maneuvering can also be difficult in tight spaces or other areas that may require the hands to be used for stability. A cane is usually used in one hand, meaning the other hand is available for stability.
Many people with long-term injuries or impediments own both a cane and crutches to accommodate different situations. A cane may be very useful for moving around a small room, or for quick trips to the bathroom or kitchen, but longer walks may require the use of crutches; a person may choose to use crutches outdoors while using a cane indoors, or vice versa. A cane is useful for people with a limp or injuries that still allow them to put weight on that leg, but crutches must be used for more severe injuries or conditions that render one leg inoperable.
It is important to keep in mind that both a cane and crutches can have adverse affects on the body when used for long periods of time. Crutches tend to chafe the armpits and can cause sores or bruises on the hands, while a cane can alter the way a person naturally walks. Since a cane forces a person to put more weight on one side of the body, the muscles of the body may tense or tighten due to the unnatural movement. Crutches often force a person to lean forward, which can cause strain on the head, neck, and shoulders.