There are several types of<unk> es: Underarm or axillary Axillary<unk> es are used by placing the pad against the ribcage beneath the armpit and holding the grip, which is below and parallel to the pad. They are usually used to provide support for patients who have temporary restriction on ambulation. With underarm<unk> es, sometimes a towel or some kind of soft cover is needed to prevent or reduce armpit injury. A condition known as<unk>  paralysis, or<unk>  palsy can arise from pressure on nerves in the armpit, or axilla. Specifically, "the brachial plexus in the axilla is often damaged from the pressure of a<unk> ...In these cases the radial is the nerve most frequently implicated; the ulnar nerve suffers next in frequency." An uncommon type of axillary<unk> es is the spring-loaded<unk> . The underarm pad is a curved design that is open in the front with the grips for the hands shaped for maximum comfort and to reduce the prevalence of overuse injuries. These<unk> es also contain a spring mechanism at the bottom. The idea behind this design is to allow the user to propel themselves further, resulting in quicker movement from place to place, though research has shown that the difference in speed is very small when comparing standard axillary<unk> es to spring-loaded<unk> es. Forearm A typical forearm<unk>  A forearm<unk>  (also commonly known as an elbow<unk> , Canadian<unk>  or "Lofstrand"<unk>  due to a brand by this name) has a cuff at the top that goes around the forearm. It is used by inserting the arm into the cuff and holding the grip. The hinged cuff, most frequently made of plastic or metal, can be a half-circle or a full circle with a V-type opening in the front allowing the forearm to slip out in case of a fall. Forearm<unk> es are the dominant type used in Europe, whether for short or long term use. Outside of Europe forearm<unk> es are more likely to be used by users with long-term disabilities, with axillary<unk> es more common for short-term use. Platform Top portion of a platform<unk>  showing platform and grip These are less common and used by those with poor hand or grip strength due to arthritis, cerebral palsy, or other conditions. The forearm rests on a horizontal platform and is usually strapped in place with velcro-type straps that allow the platform or trough to release in case of a fall. The hand holds an angled grip which, in addition, should allow adjustment of length from trough to grip and side-to-side sway depending on the user's disability. Leg support These non-traditional<unk> es are useful for users with an injury or disability affecting one lower leg only. They function by strapping the affected leg into a support frame that simultaneously holds the lower leg clear of the ground while transferring the load from the ground to the user's knee or thigh. This style of<unk>  has the advantage of not using the hands or arms while walking. A claimed benefit is that upper thigh atrophy is also reduced because the affected leg remains in use. Unlike other<unk>  designs these designs are unusable for pelvic, hip or thigh injuries and in some cases for knee injuries also. Walking sticks or canes serve an identical purpose to<unk> es, but are held only in the hand and have a limited load bearing capability because of this.
Crutch
Pedestrian
Squawk 
Splinter
Hoople 
Hairball
Cowlick
Charley horse