Use of a pushrim-activated, power-assisted wheelchair enhanced mobility for an individual with cervical 5/6 tetraplegia

Neurology Report, Mar 2003 by Somers, Martha F, Wlodarczyk, Shelby

ABSTRACT

For patients with mid-level (C5 or C6) tetraplegia, the choice between using a power or manual wheelchair is difficult because both types of wheelchairs have disadvantages. A new class of wheelchair has recently become available-the pushrim-activated, power-assisted wheelchair (PAPW)-which allows manual wheelchair propulsion with less effort. In this article the case of a patient with right CS> left C6 tetraplegia who practiced using both a manual wheelchair and a PAPW is presented. He achieved independence in manual wheelchair propulsion, but propulsion was slow and limited to short distances on smooth level surfaces. In contrast, he became independent in propelling the PAPW over a variety of surfaces for long distances at functional speeds, and in ascending and descending ramps. The patient's performance suggests that a PAPW is an alternative to a manual or power wheelchair for individuals with midlevel tetraplegia.

INTRODUCTION

A cervical spinal cord injury that results in total paralysis below the lesion [American Spinal Injury Association (ASIA) classification A or B] causes profound functional limitation in the area of mobility. As all voluntary motor function is lost in the trunk and lower extremities, functional walking is not possible. A wheelchair, therefore, is necessary for independent mobility. For this reason, wheelchair selection is an important component of rehabilitation.

Until recently, wheelchair selection has involved a choice between two major classes of wheelchair: manual and power.1 In the past manual wheelchairs were considered to be the better of these 2 options for all individuals capable of propelling them.2 This is because manual wheelchairs have a number of important advantages. They are smaller and lighter than power wheelchairs, making it possible to transport them in cars, maneuver in more confined spaces, and negotiate curbs and stairs,1 either independently or with assistance. Manual wheelchair propulsion also provides upper extremity exercise, potentially benefiting the wheelchair user's cardiovascular fitness and upper extremity muscle strength.3,4 In recent years, however, a significant disadvantage of these wheelchairs has become evident. That is over time, manual wheelchair propulsion is likely to lead to overuse injuries and pain in the upper extremities,5,8 especially in the shoulders.6-9 The risk of developing shoulder pain is particularly high among people with tetraplegia,6,10 presumably due to altered joint mechanics resulting from incomplete innervation in the upper extremities and shoulder girdle. Shoulder pain can, in turn, lead to a decline in functional abilities6,8,10,12 and interfere with community integration.13

Power wheelchairs can provide a means of independent mobility to people who are unable to propel manual wheelchairs. They also are used by some individuals who are capable of propelling manual wheelchairs, but prefer to use power wheelchairs in order to preserve energy' and to avoid subjecting their upper extremities to damaging forces. Power wheelchairs, however, have significant disadvantages. Due to their size and weight, most cannot be transported in cars or lifted over curbs and stairs. Some power wheelchairs also require more space for maneuvering, and thus their use is restricted to environments that have wide doors and passageways as well as large areas of clear floor space. Finally, since power wheelchairs are bulkier and noisier than manual wheelchairs, some people feel they make their users appear to be more disabled.1

When making the choice between a power or a manual wheelchair, the rehabilitation team and patient consider the advantages and disadvantages of each.10-16 This decision is relatively uncomplicated for most people with C7 or lower neurological level of injury. These individuals have the potential to be very functional in manual wheelchairs, typically achieving independent mobility in indoor and outdoor environments.17 Unless there are limiting factors such as cardiovascular disease or arthritis to consider, a manual wheelchair is usually the most appropriate choice.17 In contrast, people with high (C4 or higher) tetraplegia lack adequate upper extremity strength for manual wheelchair propulsion.17 Power wheelchairs are the only option for independent mobility in these cases.

The `power vs manual' decision can be more difficult for people who have C5 or C6 tetraplegia, which are 2 of the most frequently occurring levels of spinal cord injury18 Many individuals with CS or C6 tetraplegia are able to propel manual wheelchairs independently in indoor environments,17 but propel slowly19 and are likely to require assistance when negotiating outdoor terrain.17,19 Individuals who function at this level, with marginal propulsion abilities, might prefer a manual wheelchair because they can use it at home without major architectural renovations, can transport it in a car instead of having to use a van with a lift, and can ascend and descend curbs and stairs with assistance. One problem to consider, however, is that the individual with marginal propulsion abilities is likely to require assistance to propel a manual wheelchair in outdoor environments, which could greatly impede their ability to return to work or school, or participate in other community activities. As important, they are likely to develop overuse injuries and shoulder pain. A power wheelchair could solve these problems, but would bring with it the disadvantages associated with greater weight and size. Thus, there may not be a clear answer to the question of whether a manual or power wheelchair would be the best choice for an individual with marginal propulsion abilities.