While a<unk>  eliminates much of the manual strength problems of an unpowered wheelchair, its tiller steering mechanism still requires upright posture, shoulder and hand strength, and some upper-body<unk>  and strength, although the delta tiller goes some way to alleviate these constraints. The arm-rest mounted controller typical of powerchair designs may be more suitable for many users.<unk> s also have fewer options for body support, such as head or leg rests. They are rarely designed for ease of patient transfer from seat to bed. Other drawbacks include longer length, which limits their turning radius and ability to use some lifts or wheelchair-designed access technologies such as kneeling bus lifts. The longer length may also make it difficult to reach door-opener buttons or doorknobs. Some<unk>  have low ground clearance which can make it difficult to navigate certain obstacles, such as travelling in cities without proper curb cuts (aka dropped kerbs). Navigating in restricted spaces, whether in the home or in public spaces and buildings, can also be a problem. While new public buildings are usually designed with accessibility features, at least in North America, the longer length and wider turning radius may make it difficult to use them. This is a greater problem in older buildings which may have had to make compromises in retrofitting accessibility aids. For example, an elevator or lift may be adequate for a wheelchair, but too short for a<unk> . Hallways may be too narrow to make a right-angle turn. Or the "privacy" wall in most washrooms may restrict the entry so that the<unk>  cannot maneuver around it. The weight minimum and limitations may be cause for concern as well with the minimum weight requirement being 170 lbs and the maximum being between 250 and 400 pounds depending on the make. These limitations may prevent some disabled individuals from using<unk> s. In addition,<unk>  limitations may vary depending on model and manufacturer. A limitation of one make/model does not necessarily carry over to all. Individual needs may affect the suitability of a particular model. In general, four-wheel<unk> s have a larger turning radius than three-wheel<unk> s. In particular, a purchaser should compare length, width, turning radius and ground clearance to ensure the<unk>  will fit with most commonly encountered obstacles in the user's environment. Currently in the United States, Medicare will not approve a power wheelchair for persons who do not need to use the chair "inside their own home", even if their medical needs restrict the use of a<unk> . For example, a person with severe arthritis of both shoulders and hands may not be the best candidate for a<unk> , but because they can walk a few steps in their own home, such persons are not seen as approved candidates for a power wheelchair either. Various disability rights groups are campaigning for Medicare to change this policy. For those who do qualify for Medicare, they can reimburse up to 80% of the Medicare allowable value of the<unk> . Such restrictions are also applied in at least some Canadian provinces. For example, to be eligible for partial funding by the Ontario Assistive Devices Program, the user must need the<unk>  for use in their own home. Similar restrictions on NHS powerchair provision exist in the UK, with manual wheelchairs prescribed for users with any ability to walk. This has led to many users who might be better served by a powerchair privately procuring a<unk>  as a cheaper substitute.
Mobility scooter
Hip protector
Baby walker
Walking boot
Shoe insert
Vanderbilt exoskeleton
Gait trainer
Reconstructive ladder