Manual wheelchair structure
A manual wheelchair generally consists of seven parts: pusher, wheelchair frame, wheels, braking device, anti-falling device, seat and footrest.
1.Large wheels
Carry the major weight. The diameter of the wheel is 51, 56, 61, 66cm. Pneumatic tires are often used, except for a few solid tires that are required by the use environment.
2, Small wheels
There are 12, 15, 18, 20cm diameters, and the larger diameter wheels are easy to use Get over small obstacles and special carpets. However, if the diameter is too large, the space occupied by the entire wheelchair becomes larger, making it inconvenient to move. The normal small wheel is before the big wheel, but in the wheelchair for paraplegics, the small wheel is often placed after the big wheel. It should be noted that the direction of the small wheel should be perpendicular to the big wheel, otherwise it is easy to fall.
3, Handwheel rims
are unique to wheelchairs, The diameter is generally 5cm smaller than that of the large rim. When the hemiplegia is driven with one hand, an additional one with a smaller diameter is available for selection. The hand wheel rim is generally pushed directly by the patient. If the function is not good, the following changes can be made for easy driving:
(1) Add rubber on the surface of the hand wheel rim to increase the grinding force.
(2) Add a knob along the circumference of the hand wheel.
There are the following types of push handles:
①Horizontal push handle. For C5 spinal injuries. Therefore, when the biceps are healthy, the hand is placed on the push handle, and the cart can be pushed forward by flexing the elbow. If there is no horizontal push handle, it cannot be pushed.
② Vertical push handle. For rheumatoid arthritis when shoulder and hand joint movement is limited. Therefore, the horizontal push handle cannot be used.
③Bold push handle. It is used for patients with severely limited finger movement and it is difficult to make a fist. It is also suitable for patients with osteoarthritis, heart disease or the elderly.
4. Tires
There are three types of solid, inflatable and tubeless. The solid type travels faster on flat ground and is not easy to explode and is easy to push, but it vibrates greatly on uneven roads, and it is not easy to pull out when it is stuck in the groove with the same width as the tire; The vibration is smaller than the solid one; the tubeless inflatable type will not puncture because the tubeless, and the inside is also inflated, it is comfortable to sit up, but it is more difficult to push than the solid one.
5. Brakes
The big wheels should have brakes on each wheel, of course, a person with hemiplegia can only use one hand When you have to use the one-hand brake, you can also install an extension rod to operate the brakes on both sides.
There are two types of brakes:
(1) Notch brakes. This brake is safe and reliable, but more laborious. After adjustment, it can also be braked on slopes. If it is adjusted to level 1 and cannot be braked on flat ground, it is invalid.
(2) Toggle brake. Using the principle of leverage to brake after passing through several joints, its mechanical advantage is stronger than that of the notch brake, but the failure is faster. In order to increase the braking force of the patient, an extension rod is often added to the brake, but this rod is easily damaged, and safety will be affected if it is not checked frequently.
6. Chair seat
The height, depth and width of the chair depend on the patient’s body type, and the material texture also depends on the disease. Generally, the depth is 41, 43cm, the width is 40, 46cm, and the height is 45, 50cm.
7. Seat Cushion
In order to avoid pressure sores, pay close attention to the cushion, and possibly use an egg basket ( eggcrate) type or Roto pad, this pad consists of a large piece of plastic with a large number of papillary plastic hollow columns with a diameter of about 5cm, each column is soft and easy to move, and the pressure surface becomes a lot of pressure after the patient sits When the patient moves a little, the pressure point changes with the movement of the nipple, so that the pressure point can be changed continuously to avoid frequent pressure on the same part and cause pressure ulcers. If there is no such cushion, a layered foam should be used, the thickness of which should be 10cm, the upper layer is high-density polyarethane foam with a thickness of 0 and 5cm, and the lower layer is medium-density plastic of the same nature. High-density ones are supportive, and medium-density ones are soft and comfortable. In the sitting position, the ischial tubercle bears a lot of pressure, often exceeding 1 to 16 times the pressure at the normal capillary end, and is prone to ischemia to form pressure ulcers. In order to avoid excessive pressure here, a piece is often dug on the corresponding pad to make the ischial tubercle overhead. When digging, the front should be 2 or 5 cm before the ischial tubercle, and the side should be 2 or 5 cm outside the tubercle. The depth is about 7 cm to 5 cm. After digging, the cushion is in a concave shape with the gap behind. If the above cushion is used with an incision, it can effectively prevent the occurrence of pressure ulcers.
8, Foot and leg rests
The leg rests can be straddled or separated , both of which are ideal for swinging to one side and removable. Attention must be paid to the height of the footrest. If the foot support is too high, the hip flexion angle is too large, and more weight is added to the ischial tuberosity, which is easy to cause pressure ulcers there.
9, Backrest
The backrest has height and can be tilted or not. If the patient has good balance and control of the trunk, a wheelchair with a low backrest can be used to enable the patient to have a greater range of motion. Instead, use a high-back wheelchair.
10, armrests or arm rests
Generally 22, 5~25cm higher than the seat surface, some arm rests can be Adjust the height. A lapboard can also be placed on the arm rest for reading and dining.
Declare: The above methods are derived from the program system index or shared by netizens. They are for your reference only and do not represent the research views of this website. sex and authority.
