Wheelchair mobility

Chapter 4

Wheelchair mobility

Wheelchair mobility is fundamental to the independence of people who are unable to walk. This chapter describes ways of mobilizing with power and manual wheelchairs. It also provides details of how people in manual wheelchairs negotiate obstacles such as kerbs, ramps, grassy slopes and stairs.

Neurological loss is an important determinant of wheelchair mobility. The level of wheelchair mobility typically attained by people with tetraplegia and paraplegia can be summarized as follows:

People with C1–C4 tetraplegia. People with C1–C4 tetraplegia use a chin-control or mouth-operated power wheelchair. Most also use manual wheelchairs pushed by others when going to places where they are likely to need lifting up and down stairs, or if the wheelchair needs to be stowed in the boot of a car.

People with C5 tetraplegia. People with C5 tetraplegia primarily use a hand-control power wheelchair. They can push a manual wheelchair on flat smooth surfaces but require assistance elsewhere.

People with C6–C8 tetraplegia. Most people with C6–C8 tetraplegia primarily use a manual wheelchair. Few attain advanced levels of wheelchair mobility and most require assistance to negotiate awkward terrains. Some may, at least initially, have difficulty performing apparently simple tasks such as turning the wheelchair. Those with C8 tetraplegia attain a higher level of mobility than those with C6 tetraplegia because of superior hand and upper limb function. Nearly all use a power wheelchair when traversing long distances or uneven and difficult terrains.

People with paraplegia. Most people with paraplegia rely solely on a manual wheelchair. They attain more advanced levels of wheelchair mobility than people with low levels of tetraplegia, and most can negotiate ramps and uneven ground with practice. Some that are young and agile can negotiate stairs, kerbs and grassy slopes, and can perform other difficult manouvres.^1,²

Mobilizing with power wheelchairs

Patients dependent on power wheelchairs can readily negotiate flat ground and most ramps, but not other obstacles. Driving a power wheelchair requires practice especially for patients with C1–C4 tetraplegia who use chin- or mouth-control mechanisms. Patients with C5 tetraplegia who are capable of using hand-control mechanisms generally have less difficulty learning to control power wheelchairs, although poor shoulder strength can make control difficult.

There are many types of mouth-, chin- and hand-control mechanisms which can be triggered in different ways.³ Control mechanisms can be electronically programmed to vary power-related features of the wheelchair including sensitivity, acceleration, cut-out and speed (see Chapter 13).⁴

Patients need to practise driving their wheelchairs on the types of terrains they are likely to encounter. This is important not only because it provides context-specific learning of mouth-, chin- or hand-control mechanisms, but also because it provides an opportunity to learn which environmental situations can and cannot be safely negotiated. For instance, wheelchairs can topple during negotiation of highly cambered surfaces or while descending and ascending steep grassy slopes. Initially patients need to practise in a safe environment such as a basketball court or physiotherapy gymnasium. Patients can then progress to more difficult environments.

Initially close supervision may be necessary when negotiating difficult terrains. The physiotherapist may need to stand alongside the wheelchair ready to stabilize it if necessary. Most power wheelchairs have ‘kill’ switches for training purposes. These are controlled by the physiotherapist and when activated instantly cut power to the wheelchair.

The ability to control an electrical wheelchair also relies on correct positioning in the wheelchair. Patients with high levels of tetraplegia do not have the ability to reposition themselves and consequently are dependent on how others position them. Subtle changes in position, especially a change in the alignment of the arms or heads with respect to the control mechanism, can render a patient incapable of driving the wheelchair. Changes in position may occur if patients slide forwards on their cushions or if they are jolted or knocked while traversing bumpy ground. The trunk can also be pitched forwards when descending steep slopes.⁵ Chest or arm straps and moulded backrests can be used to help maintain an appropriate position. The tilt of the wheelchair and the angle of the backrest can also be manipulated to place patients in a less vertical and more stable position (see Chapter 13).

Mobilizing with manual wheelchairs

When patients first sit in manual wheelchairs they need to be taught basic skills such as how to apply and release the brakes, remove the arm rests and footplates, and turn the wheelchair. They can practise manoeuvring and reversing in tight spaces and negotiating around obstacles. There are also some simple tricks patients can be taught which are particularly important for those with tetraplegia and limited upper limb strength.¹ For example, an arm placed on the wall can be used to help turn a corner (see Figure 4.1).

Figure 4.1 An arm placed on the wall can be used to turn a corner.

The wheelstand as the basis of advanced mobility

The wheelstand (also called a ‘wheelie’) is the basis of advanced wheelchair mobility.³ It involves rotating the wheelchair on its back axle so the front castors lift up off the ground (see Figure 4.2). The ability to perform this manoeuvre enables patients to descend grassy slopes, negotiate kerbs and small obstacles, and turn in tight spaces.

Figure 4.2 The amount of tilt required to perform a wheelstand depends on the location of the wheelchair’s rear axle (i.e. the wheelbase, WB). If the axle is located posteriorly, as in (a), the front castors need to lift well off the ground to attain the balanced position. In contrast, if the axle is located more anteriorly, as in (b), the front castors only need to just lift off the ground.

Training advanced wheelchair skills requires appropriate supervision to ensure patient safety. Physiotherapists must anticipate how patients may fall and position themselves appropriately to intervene if necessary. For example, patients are most likely to fall backwards when learning to descend a kerb backwards, and they are most likely to fall forwards when learning to ascend a kerb forwards. In both scenarios, physiotherapists need to stand at the kerb anticipating how the patient is most likely to fall and ready to provide assistance if necessary. Therapists need to guard against potential falls without interfering with the patient’s attempts at performing the wheelchair skill. A spotter training strap can be used for this purpose.^6,⁷ The strap is attached to the under-frame of the wheelchair (see Figure 4.3). The physiotherapist holds one end of the strap, pulling on it if the wheelchair rotates too far backwards. This returns the wheelchair onto its four wheels, averting a backward fall. The physiotherapist still needs to stand close to the wheelchair so the weight of a backward-tipping wheelchair can be shared between the strap and the physiotherapist’s thigh. The spotter training strap can also be used when patients practise controlling a wheelchair down a slope. In this instance the strap is used as a breaking device in case the patient loses control of the wheelchair.

Figure 4.3 A spotter training strap. This can be used to prevent a backwards fall in patients learning to perform wheelstands.⁷

Only gold members can continue reading. Log In or Register to continue

Related

Stay updated, free articles. Join our Telegram channel

Tags: Management of Spinal Cord Injuries A Guide for Physiotherapists

Mar 13, 2017 | Posted by admin in PHYSICAL MEDICINE & REHABILITATION | Comments Off

Full access? Get Clinical Tree

Get Clinical Tree app for offline access

Get Clinical Tree app for offline access