Detailed Structure of Manual Wheelchair
Because the price is relatively cheap, manual wheelchairs are still the main force in the market. Compared with electric wheelchairs, manual wheelchairs are not only more affordable, but also suitable for people with handicapped legs and feet who can take care of themselves and have stronger mobility. What are the structural components of a manual wheelchair? A manual wheelchair is generally composed of seven parts: a push handle, a wheelchair frame, wheels, a brake device, an anti-backward device, a seat and a foot pedal. Next, let's take a look at the detailed introduction.
Manual wheelchair structure
Manual wheelchairs are generally composed of seven parts: push handles, wheelchair frames, wheels, brake devices, anti-backward devices, seats and pedals.
1. Big wheels
Carries the main weight. The diameters of the wheels are 51, 56, 61, and 66 cm. Solid tires and pneumatic tires are often used
2. There are several types of small wheels with diameters of 12, 15, 18, and 20 cm. Small wheels with large diameters are easy to cross 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. Normally the small wheel is before the big wheel, but in wheelchairs for lower limb amputee, 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. Hand ring
Unique to wheelchairs, the diameter is generally 5cm smaller than the large rim. When the hemiplegia is driven with one hand, another one with a smaller diameter can be selected. The hand wheel is generally pushed directly by the patient. If the function is not good, it can be changed in the following ways for easy driving: moving,
a. Add rubber to the surface of the hand wheel to increase friction.
b. Add a push handle (knob) around the hand wheel rim.
There are several types of push handles:
0 level push handle. For C5 spinal injuries. Therefore, the biceps of the brain are healthy, and the hands are placed on the push handle, and the cart can be pushed forward by bending force. If there is no horizontal push handle, it cannot be pushed.
2 Vertical push handles. For rheumatoid arthritis shoulder and hand joints with limited mobility. Therefore, the horizontal push handle cannot be used
0 Bold push handle. It is used for patients with severely limited finger movement and is not easy to make a fist. It is also suitable for osteoarthritis, heart disease or elderly patients.
4. There are three kinds of tires: solid tire, pneumatic inner tube and tubeless pneumatic tire. The solid type walks 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 one with an inflated inner tube is more difficult to push and easy to puncture, but The vibration is smaller than the solid one: the tubeless inflatable type will not be punctured because of the tubeless tube, and the inside of the eye is also inflated, so it is comfortable to sit, but it is harder to push than the solid one
5. Braking
The large wheels should have brakes on each wheel. Of course, when a hemiplegic can only use one hand, he has to use one hand to brake, but an extension rod can also be installed to control the brakes on both sides.
There are two types of brakes:
1) Notched brakes. This brake is safe and reliable, but more laborious. After adjustment, it can also brake on slopes. If it is adjusted to level 1 and cannot brake on flat ground, it is invalid. (2) Seasonal brakes. Utilizing the principle of leverage, passing through the joints of several people and then braking, its mechanical advantage is stronger than that of the notch brake, but it fails faster. In order to increase the patient's brake, an extension rod is often added to the brake, but this rod is easy to damage, and it will affect safety if it is not checked frequently.
6. Seat
Its height, depth, and width depend on the body shape of the patient, and its 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 pads. It is possible to use eggcrate or Roto pads as much as possible. This pad is composed of a large piece of plastic with a large number of nipple-shaped plastic hollow columns with a diameter of about 5 cm. Each column is Soft and easy to move, the pressure surface becomes a large number of pressure points after the patient sits on it, and when the patient moves a little, the pressure points change with the movement of the nipple, so that the pressure points can be constantly changed to avoid frequent pressure on the same part cause pressure sores. If there is no above-mentioned cushion, you need to use layered foam plastics, the thickness of which should be 10cm, the upper layer is 0.5m thick high-density polychloroformic acid enzyme (polvarethane) foam plastics, the lower layer is plastic of the same nature with medium density, high Density is supportive, medium density is soft and comfortable. When sitting, the ischial tubercle bears a lot of pressure, which often exceeds the pressure of the normal capillary end by 1 to 16 times, and it is easy to form a pressure sore due to ischemia. In order to avoid excessive pressure here, often dig a piece of the mat at the corresponding place to let the ischial tuberosity be elevated. The front of the control time should be 2.5 cm in front of the ischial tubercle, and the side should be 2.5 cm outside the tubercle. The depth is about 7.5cm. After digging, the cushion is in the shape of a font, and the gap is at the back. If the above-mentioned cushion is used and the incision is used, the occurrence of pressure sores can be prevented quite effectively.
8. Foot support and leg support
The leg support can be straddling the two sides, or the two sides are separated, both of which can be swung to one side and can be disassembled as the most ideal. Attention must be paid to the height of the footrest. If the foot support is too high, the angle of the marrow flexion will be too large, and the weight will be added to the ischial tuberosity, which will easily cause pressure sores there.
9. Backrest
The backrest can be divided into high and low, tiltable and non-tiltable. If the patient has good balance and control of the trunk, a wheelchair with a low backrest can be selected so that the patient can have greater mobility; otherwise, a wheelchair with a high backrest should be selected.
10. Armrest
Generally, it is 22, 5~25cm higher than the seat surface, and some arm rests can be adjusted in height. An apboard can also be placed on the upper shelf of the armrest for reading and dining.
