WORK A Journal of Prevention,
Assessment & Rehabilitation
ELSEVIER
Work 8 (1997) 261-266
Physical disabilities and their implications driving Carmella M. Strano* MossRehab Hospital, Driving School/or People with Disabilities, lCC Klein Branch, Suite 210, 10100lamisonAvenue, Philadelphia, PA 19116, USA
Received 16 January 1996; accepted 30 January 1996
Abstract A brief overview of a variety of physical disabilities categorized as brain injured and non-brain injured are presented as they relate to independent driving. Adaptive driving aids, and driving systems as well as financial considerations and the role of the driver rehabilitation specialist in providing comprehensive driver assessments are discussed. A case study is included to demonstrate range of available driving equipment for persons with severe disabilities. © 1997 Elsevier Science Ireland Ltd. Keywords: Brain injury; Adaptive driving aids
1. Introduction
There is no doubt that the ability to travel independently has a major impact on vocational potential. Job opportunities are greatly enhanced for the individual who is able to independently transport themselves to and from a work place. Public transportation is available in most of our urban areas. However, as more and more of our industries move from urban to suburban locations, and federal funding to help support public transportation services is reduced, the ability to drive independently becomes more important if
* Corresponding author. Tel.: + 1 215 6736559; fax: + 1 215 6769593.
one is to avail oneself of available job opportunities. This is no less true for the person with a physical disability. Accessible transportation, either through the public transportation system or through share-a-ride door to door services, remains limited. To become a productive member of society and to interact socially with friends and family, it is essential that this population has a means of independent transportation. For many persons with a disability, this has become a realistic goal due to the currently available automotive technology. Driving systems capable of accommodating even the most severe physical disabilities are now commercially available. However, the ability to drive involves more than finding the
1051-9815/97/$17.00 © 1997 Elsevier Science Ireland Ltd. All rights reserved. PlI S 1051-9815(96) 00245-3
262
CM. Strano / Work 8 (1997) 261-266
right equipment to compensate for a physical deficit. Driving is a complex skill involving the integration of cognitive, visual and motor skills. Assessment of an individuals ability to safely operate a motor vehicle should be performed by persons who have a knowledge of the elements of various disabilities, a working knowledge of available driving devices and systems and a through understanding of the components of the driving task. More and more physicians, other members of the medical community, and concerned family members are turning to the Driver Rehabilitation Specialist (DRS) for driver evaluation services to assist them in determining when and if a person is capable of safely operating a motor vehicle. The DRS is the specialist who is most aware of the sequel commonly associated with a variety of disabilities to determine what assessments are appropriate and what benefit, if any, will be gained from adaptive driving equipment or driver training. The following is a brief overview of the impact and implications a disability may have on ability to drive independently. 2. Driver assessments For the purpose of performing a driver's assessment, disabilities may be divided into several large categories: brain injured vs. non-brain injured, previous driver vs. new driver and progressive vs. static conditions. 2.1. Brain injured driving evaluations
The brain injured (BI) category of drivers may include those with previous driving experience and those without such experience. This category is usually those persons who have a disability that may include some degree of cerebral or central nervous system involvement. This includes such disabilities as Cerebral Vascular Accidents (CVA), Cerebral Palsy (CP), Spina Bifida, Multiple Sclerosis (MS) and Traumatic Brain Injury (TBI). In each case, etiology of the cerebral involvement may be different but they share many common problems that may affect their ability to drive. Vision has been identified as one of the most important ways information is taken in while driv-
ing (Wylie, 1978). Visual acuity is defined as a measure of the eye's ability to distinguish object details and shapes (Carson, 1984). AlISO states have a VA requirement for driving. It is acuity for distance (far point) rather than near point that is tested. While this is an important function to assess for all drivers, it is more likely to be impaired in those clients who fall within the BI diagnostic categories. However, this is one of the few visual functions that is highly correctable, with detection and referral for corrective lenses, in all persons. Frequently in acquired disabilities such as CVA and TBI, this is a function that will improve without intervention over time. Peripheral vision enables a driver to gather information from the left and right sides of the environment while looking straight ahead. It plays an important role in ability to maintain lane position, control the speed of one's vehicle, and increase awareness of other vehicles. A peripheral field deficit may be an acquired deficit or may be the result of birth trauma. Although deficits in visual fields (VF) may occur in combination with many disabilities, they are more likely to occur in persons with a diagnosis of CVA or traumatic brain injury. In these cases the length of time since the onset of the disability becomes an important consideration. Frequently VF deficits will recover for as long as 1 year post-CVA and longer for the TBI. The American Medical Associations's Committee on Medical aspects of Auto Safety has recommended that states require 140 of peripheral vision measured along the horizontal plane for driving. However, this standard has not been adopted by every state. Since VF requirements do vary from state to state it is important to evaluate the extent of any visual field deficit to determine whether an individual is in compliance with the law in the state in which they are licensed. Knowing the extent of any field loss will assist the DRS in determining whether it will be possible to compensate for the loss. For individuals with demyelinating diseases, such as multiple sclerosis, visual field deficits are also a possible finding and are more likely to occur as scotoma scattered within the visual field. Vehicles entering one of these blind areas can virtually be lost to the driver. Moreover, these 0
CM. Strano / Work 8 (J997) 261-266
individuals are frequently unaware of their deficit and do not practice the visual vigilance necessary to drive safely. This population is also more likely to have deficits in color perception and contrast sensitivity (Regan, 1977) which may make it more difficult for them to drive at. night or in bright sunlight. Eye motility which includes range of motion of the eyes as well as saccadic movements has been found to be an extremely important function relative to the driving task. This is particularly true for the ability to perform a visual saccade. This is the ability to move one's eyes from one place to another in a smooth, precise movement. While deficits in the range of motion of the eyes can be compensated for with head movement, the same is not true of an inaccurate or erratic saccade. These individuals are frequently described by the DRS as being 'all over the road'. Eye movement disorders are estimated to be present in 50% of persons with Cerebral Palsy (Diamond, 1959). An individual who has an accurate awareness of both sides of their body and their limbs in space, is more likely to be aware of the outer limits of their vehicle in relation to other vehicles and lane position. This may account for the reason that persons with a brain injury with sensory deficits affecting one side of their body appear to be more likely to have difficulty with position in space tasks. A lane finding deficit resulting from a sensory loss is difficult to distinguish from the same behind-the-wheel (BTW) performance of individuals with cognitive and perceptual deficits. Webster defines Cognition as: 'awareness; state of being able to perceive objects or remember ideas; the act or process of knowing, including both awareness and judgment.' Cognitive testing has become the catch-all-category for evaluation of one's ability to perceive, remember, attend to multiple stimuli and problem solve to name just a few. Visual perception is the ability to process visual information. Testing of the BI client may include a variety of assessments which take one or all of these functions into account. While it appears to be evident that intact skills in these areas should be necessary to drive in a safe manner, the relationship between deficits in these areas and driving ability has not been firmly es-
263
tablished (Katz, 1990; van Zomeren, 1987). Many DRSs will include some degree of evaluation of cognitive/perceptual skills but the results of most driver assessments relies heavily on actual behind-the-wheel performance. However, testing of these functions does provide the evaluator with some basis for explaining results of the BTW performance to the client, physicians and family members. There is some evidence to suggest that cognitive deficits and/or perceptual deficits depending on their degree, will yield a driver who drifts to one side or the other of a traffic lane, uses poor judgment in determining right-of-way situations and in general is unaware of changing traffic conditions. Persons who fall within the HI diagnostic category are usually semi-ambulatory. That is, they are able to ambulate with the aid of crutches, canes and walkers. Interestingly this is the diagnostic category which usually requires the simplest if any adaptive driving equipment. Adaptive driving aids may be necessary if the individual has lost the use of an upper and/or lower extremity or both lower extremities. These aids consist of mechanical add-on devices that attach to the existing gas and brake pedals or to the rim of the steering wheel. They range from steering aids through left foot gas pedals and hand controls. The amount of training required will depend on the amount of previous driving experience, the presence of any visual, cognitive or perception deficits and their age. Younger individuals tend to learn to use adaptive driving aids with greater ease than older drivers. 2.2. Non-brain injured driver evaluation
The non-brain categories referred for driver rehabilitation may include spinal cord injuries, the dystrophies, both congenital and traumatic limb amputations, orthopedic malformations, arthritis and hearing impaired, to name a few. For this group of disabilities, the task of the driver rehabilitation specialist becomes primarily one of finding the right combination of driving equipment to substitute for missing limbs or function. There has been some controversy (Davidoff,
264
CM. Strano / Work 8 (1997) 261-266
1988) as to whether or not individuals who have sustained a traumatic spinal cord injury also have a brain injury. The dynamics of any accident, particularly those related to a motor vehicle accident, may cause, in addition to the actual physical injuries, some contusion to the brain to a lesser or greater degree. The brain, because it is encased in a hard unyielding shell, but is not physically attached to that shell, is bounced around within this cavity during the extreme forces involved in a motor vehicle accident. However, since driver rehabilitation is a service usually provided when the client's overall condition has stabilized and rehabilitation efforts have been exhausted, the primary disability to be considered by the DRS is the spinal cord injury. For the purposes of a driver's evauation, they are usually considered as part of the non- brain injured population. With the exception of disabilities which have no physical limitations, such as hearing impairment, this category of clients are more likely to be non-ambulatory or have very limited ambulatory capability. The DRS may need to consider whether the client is able to transfer to and from an automobile seat and if they will be able to independently load their wheelchair into their vehicle. This will depend not only on the physical capabilities of the client but on the accessible storage area available to them in their vehicle and to the type of WC they are utilizing. Many clients are prescribed WCs which although they are lighter in weight, do not fold narrow enough to fit behind the front seat of an automobile. Chairs with rigid frames are becoming more popular because they are generally more comfortable and provide better support. The ability of the client to dismantle and load the individual parts of their chair into their vehicle should always be considered. There are available a wide variety of electrically powered wheelchair loading devices for the manual folding wheelchair that will assist with storage in or on top of an automobile. However, their effectiveness can be negated by a chair that does not fold to a sufficient degree. If you add to this the number of clients who are now receiving triwheelers and other electric mobility devices, it becomes apparent that for many a modified van is the vehicle of choice.
Vans modified with a fully automatic door opening and a lift, or in the case of a lowered-floor mini van, a ramp, are becoming more and more popular. These van conversions allow easy access to the vehicle and the driving compartment. These conversions are, however, extremely expensive. Driving equipment, and van conversions are usually not covered by third party payers with the exception of those clients covered by workman's compensation or vocational rehabilitation services. In many cases financial support is only provided if independent transportation will lead to employment. For the individual who is unable to transfer from their WC independently, driving a van from their WC may be the only option available to them. This is the driving population who will reap the greatest benefit from the availability of the wide range of highly technical driving systems currently available. These may range from modification of steering systems that greatly reduce the amount of effort required to maneuver the vehicle, to systems that can be operated with just the use of one partially functioning extremity to accelerate, brake and maneuver the vehicle. The wide range of sophisticated driving systems currently available can best be appreciated with the following case example. Kurt is a 21-year-old young man with a diagnosis of Phocomelia. This is a genetic disorder characterized by the absence of formation of one or more long bones in a person's arms or legs. In Kurt's case, it resulted in an absence of both arms and hands and a shortening of his right leg with his right foot attached directly to his femur. This resulted in a relatively non-functional right lower extremity. He is able to ambulate because of good use of this left lower extremity and a specially constructed prosthetic device which accommodated his partial right lower extremity. As is the case with many persons born without the use of upper extremities, he is quite adept at using his left foot for many functions we normally relegate to our upper extremities. Because of the amount of functional ability he had acquired in his left lower extremity, it was determined during an evaluation by the DRS, that he was able to operate a system commonly referred to as a joystick. This is an electronic system that incorporates gas,
CM. Strano / Work 8 (1997) 261 - 266
brake and steering functions into one upright lever or 'joystick.' While it was designed for use with one upper extremity, it was flexible enough so that with the assistance of the system's manufacturer it was able to be installed on the floor of a van for use with his left foot (Fig. 1). Additionally, all of the controls necessary to operate the accessory controls, such as windshield wipers,
265
lights, and climate controls, were incorporated into a dash-mounted computer control panel. Actual operation of the control panel was through an electric headrest equipped with a head-operated switch. In addition to the operation of the accessory controls computer, the headrest contains the switches to operate horn, and turn signals. Needless to say, a system with this level of
Fig. 1. Foot controlled driving system.
266
CM. Strano / Work 8 (1997) 261 -266
sophistication requires a considerable number of hours of training before the client is proficient in its' use. In considering any van modification the actual changes to the structure of the vehicle itself are of great concern to the DRS. With the exception of the work done by the Society of Automotive Engineers Adaptive Devices Committee, there are few if any regulations governing the extensive modifications that may be necessary to accommodate a WC driver in a vehicle. Most DRSs look to this agency for guidelines in recommending van structural modifications (SAE 11725, 1995), and for hand control (SAE 11903, 1990) and WC lift operation and installation (SAE J2093, 1995). Since most of the individuals who will require extensive vehicle modification in order to drive are doing so from their WC, the method of securing the WC to the vehicle structure is of utmost importance (SAE J2249, 1996). For the individual driving from a WC, height in the driving compartment, location of driving controls and access to same become critical. Last but not the least, an important aspect of a driving assessment is the final evaluation or checkout of recommended driving equipment. This may be performed after any vehicle conversion but is more likely to be required after an extensive van modification. This check-out provides the DRS with the opportunity to ensure that the equipment, as ordered, has been provided and that the client is able to operate it in it's current configuration. 3. Conclusion
Driving is a privilege that most of us take for granted. Independent transportation can greatly enhance the opportunities available for employment for the person with a disability. However, driving is a privilege and, unfortunately, it may not be possible for every individual with a physical impairment to accomplish this complex and often costly task. The driving task should be
viewed as an integrated system which encompasses the individual's physical and mental capabilities as well as the availability of the driving equipment. It is highly recommended that persons who have a physical disability receive a thorough driver's evaluation prior to the installation of any driving equipment in their vehicle. It is the responsibility of the DRS to ensure that the driver with a disability is as competent to drive as their non-disabled counterpoint and that any equipment recommended meets currently accepted manufacturing and installation standards. References
Cassis, B. (1984) Dictionary of Eye Tenninology. Gainesville, FL: Tread Publishing. Davidoff, G., Thomas, P., Johnson, M., Dijkers, M., Berent, S., and Doljanac, R. (1988) Closed head injury in acute traumatic spinal cord injury: incidence and risk factors. Arch. Phys. Med. Rehabil. 69, 869-871. Diamond, S. (1959) Ocular evaluation of the cerebral palsied child. Am. J. Ophthalmol. 59, 721-730. Regan, D., Silver, R., and Murray, T.F. (1977) Visual acuity and contrast sensitivity in multiple scherosis - hidden visual loss: an auxiliary diagnostic test. Brain 100,563-579. Society of Automotive Engineers, 11725 (1995) Structural Modifications for Personally Licensed Vehicles to Meet the Transportation Needs of Persons with Disabilities. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. Society of Automotive Engineers, 11903, 1990. Automotive Adaptive Driver Controls, Manual. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. Society of Automotive Engineers, 12093, 1995. Design Considerations for Wheelchair Lifts for Entry to or Exit from a Personally Licensed Vehicle. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. SAE 12249 (1996) Wheelchair Tiedowns and Occupant Restraints for Use in Motor Vehicles. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. Wylie, E.J. (1978) Vision and Driving. Canad. J. Optometry 40,70-74. van Zomeren, A.H., Brouwer, W.H. and Minderhoud, J.M. (1987) Acquired Brain Damage and Driving: A Review. Arch. Phys. Med. Rehabil. 68, 697-705.
Assessment & Rehabilitation
ELSEVIER
Work 8 (1997) 261-266
Physical disabilities and their implications driving Carmella M. Strano* MossRehab Hospital, Driving School/or People with Disabilities, lCC Klein Branch, Suite 210, 10100lamisonAvenue, Philadelphia, PA 19116, USA
Received 16 January 1996; accepted 30 January 1996
Abstract A brief overview of a variety of physical disabilities categorized as brain injured and non-brain injured are presented as they relate to independent driving. Adaptive driving aids, and driving systems as well as financial considerations and the role of the driver rehabilitation specialist in providing comprehensive driver assessments are discussed. A case study is included to demonstrate range of available driving equipment for persons with severe disabilities. © 1997 Elsevier Science Ireland Ltd. Keywords: Brain injury; Adaptive driving aids
1. Introduction
There is no doubt that the ability to travel independently has a major impact on vocational potential. Job opportunities are greatly enhanced for the individual who is able to independently transport themselves to and from a work place. Public transportation is available in most of our urban areas. However, as more and more of our industries move from urban to suburban locations, and federal funding to help support public transportation services is reduced, the ability to drive independently becomes more important if
* Corresponding author. Tel.: + 1 215 6736559; fax: + 1 215 6769593.
one is to avail oneself of available job opportunities. This is no less true for the person with a physical disability. Accessible transportation, either through the public transportation system or through share-a-ride door to door services, remains limited. To become a productive member of society and to interact socially with friends and family, it is essential that this population has a means of independent transportation. For many persons with a disability, this has become a realistic goal due to the currently available automotive technology. Driving systems capable of accommodating even the most severe physical disabilities are now commercially available. However, the ability to drive involves more than finding the
1051-9815/97/$17.00 © 1997 Elsevier Science Ireland Ltd. All rights reserved. PlI S 1051-9815(96) 00245-3
262
CM. Strano / Work 8 (1997) 261-266
right equipment to compensate for a physical deficit. Driving is a complex skill involving the integration of cognitive, visual and motor skills. Assessment of an individuals ability to safely operate a motor vehicle should be performed by persons who have a knowledge of the elements of various disabilities, a working knowledge of available driving devices and systems and a through understanding of the components of the driving task. More and more physicians, other members of the medical community, and concerned family members are turning to the Driver Rehabilitation Specialist (DRS) for driver evaluation services to assist them in determining when and if a person is capable of safely operating a motor vehicle. The DRS is the specialist who is most aware of the sequel commonly associated with a variety of disabilities to determine what assessments are appropriate and what benefit, if any, will be gained from adaptive driving equipment or driver training. The following is a brief overview of the impact and implications a disability may have on ability to drive independently. 2. Driver assessments For the purpose of performing a driver's assessment, disabilities may be divided into several large categories: brain injured vs. non-brain injured, previous driver vs. new driver and progressive vs. static conditions. 2.1. Brain injured driving evaluations
The brain injured (BI) category of drivers may include those with previous driving experience and those without such experience. This category is usually those persons who have a disability that may include some degree of cerebral or central nervous system involvement. This includes such disabilities as Cerebral Vascular Accidents (CVA), Cerebral Palsy (CP), Spina Bifida, Multiple Sclerosis (MS) and Traumatic Brain Injury (TBI). In each case, etiology of the cerebral involvement may be different but they share many common problems that may affect their ability to drive. Vision has been identified as one of the most important ways information is taken in while driv-
ing (Wylie, 1978). Visual acuity is defined as a measure of the eye's ability to distinguish object details and shapes (Carson, 1984). AlISO states have a VA requirement for driving. It is acuity for distance (far point) rather than near point that is tested. While this is an important function to assess for all drivers, it is more likely to be impaired in those clients who fall within the BI diagnostic categories. However, this is one of the few visual functions that is highly correctable, with detection and referral for corrective lenses, in all persons. Frequently in acquired disabilities such as CVA and TBI, this is a function that will improve without intervention over time. Peripheral vision enables a driver to gather information from the left and right sides of the environment while looking straight ahead. It plays an important role in ability to maintain lane position, control the speed of one's vehicle, and increase awareness of other vehicles. A peripheral field deficit may be an acquired deficit or may be the result of birth trauma. Although deficits in visual fields (VF) may occur in combination with many disabilities, they are more likely to occur in persons with a diagnosis of CVA or traumatic brain injury. In these cases the length of time since the onset of the disability becomes an important consideration. Frequently VF deficits will recover for as long as 1 year post-CVA and longer for the TBI. The American Medical Associations's Committee on Medical aspects of Auto Safety has recommended that states require 140 of peripheral vision measured along the horizontal plane for driving. However, this standard has not been adopted by every state. Since VF requirements do vary from state to state it is important to evaluate the extent of any visual field deficit to determine whether an individual is in compliance with the law in the state in which they are licensed. Knowing the extent of any field loss will assist the DRS in determining whether it will be possible to compensate for the loss. For individuals with demyelinating diseases, such as multiple sclerosis, visual field deficits are also a possible finding and are more likely to occur as scotoma scattered within the visual field. Vehicles entering one of these blind areas can virtually be lost to the driver. Moreover, these 0
CM. Strano / Work 8 (J997) 261-266
individuals are frequently unaware of their deficit and do not practice the visual vigilance necessary to drive safely. This population is also more likely to have deficits in color perception and contrast sensitivity (Regan, 1977) which may make it more difficult for them to drive at. night or in bright sunlight. Eye motility which includes range of motion of the eyes as well as saccadic movements has been found to be an extremely important function relative to the driving task. This is particularly true for the ability to perform a visual saccade. This is the ability to move one's eyes from one place to another in a smooth, precise movement. While deficits in the range of motion of the eyes can be compensated for with head movement, the same is not true of an inaccurate or erratic saccade. These individuals are frequently described by the DRS as being 'all over the road'. Eye movement disorders are estimated to be present in 50% of persons with Cerebral Palsy (Diamond, 1959). An individual who has an accurate awareness of both sides of their body and their limbs in space, is more likely to be aware of the outer limits of their vehicle in relation to other vehicles and lane position. This may account for the reason that persons with a brain injury with sensory deficits affecting one side of their body appear to be more likely to have difficulty with position in space tasks. A lane finding deficit resulting from a sensory loss is difficult to distinguish from the same behind-the-wheel (BTW) performance of individuals with cognitive and perceptual deficits. Webster defines Cognition as: 'awareness; state of being able to perceive objects or remember ideas; the act or process of knowing, including both awareness and judgment.' Cognitive testing has become the catch-all-category for evaluation of one's ability to perceive, remember, attend to multiple stimuli and problem solve to name just a few. Visual perception is the ability to process visual information. Testing of the BI client may include a variety of assessments which take one or all of these functions into account. While it appears to be evident that intact skills in these areas should be necessary to drive in a safe manner, the relationship between deficits in these areas and driving ability has not been firmly es-
263
tablished (Katz, 1990; van Zomeren, 1987). Many DRSs will include some degree of evaluation of cognitive/perceptual skills but the results of most driver assessments relies heavily on actual behind-the-wheel performance. However, testing of these functions does provide the evaluator with some basis for explaining results of the BTW performance to the client, physicians and family members. There is some evidence to suggest that cognitive deficits and/or perceptual deficits depending on their degree, will yield a driver who drifts to one side or the other of a traffic lane, uses poor judgment in determining right-of-way situations and in general is unaware of changing traffic conditions. Persons who fall within the HI diagnostic category are usually semi-ambulatory. That is, they are able to ambulate with the aid of crutches, canes and walkers. Interestingly this is the diagnostic category which usually requires the simplest if any adaptive driving equipment. Adaptive driving aids may be necessary if the individual has lost the use of an upper and/or lower extremity or both lower extremities. These aids consist of mechanical add-on devices that attach to the existing gas and brake pedals or to the rim of the steering wheel. They range from steering aids through left foot gas pedals and hand controls. The amount of training required will depend on the amount of previous driving experience, the presence of any visual, cognitive or perception deficits and their age. Younger individuals tend to learn to use adaptive driving aids with greater ease than older drivers. 2.2. Non-brain injured driver evaluation
The non-brain categories referred for driver rehabilitation may include spinal cord injuries, the dystrophies, both congenital and traumatic limb amputations, orthopedic malformations, arthritis and hearing impaired, to name a few. For this group of disabilities, the task of the driver rehabilitation specialist becomes primarily one of finding the right combination of driving equipment to substitute for missing limbs or function. There has been some controversy (Davidoff,
264
CM. Strano / Work 8 (1997) 261-266
1988) as to whether or not individuals who have sustained a traumatic spinal cord injury also have a brain injury. The dynamics of any accident, particularly those related to a motor vehicle accident, may cause, in addition to the actual physical injuries, some contusion to the brain to a lesser or greater degree. The brain, because it is encased in a hard unyielding shell, but is not physically attached to that shell, is bounced around within this cavity during the extreme forces involved in a motor vehicle accident. However, since driver rehabilitation is a service usually provided when the client's overall condition has stabilized and rehabilitation efforts have been exhausted, the primary disability to be considered by the DRS is the spinal cord injury. For the purposes of a driver's evauation, they are usually considered as part of the non- brain injured population. With the exception of disabilities which have no physical limitations, such as hearing impairment, this category of clients are more likely to be non-ambulatory or have very limited ambulatory capability. The DRS may need to consider whether the client is able to transfer to and from an automobile seat and if they will be able to independently load their wheelchair into their vehicle. This will depend not only on the physical capabilities of the client but on the accessible storage area available to them in their vehicle and to the type of WC they are utilizing. Many clients are prescribed WCs which although they are lighter in weight, do not fold narrow enough to fit behind the front seat of an automobile. Chairs with rigid frames are becoming more popular because they are generally more comfortable and provide better support. The ability of the client to dismantle and load the individual parts of their chair into their vehicle should always be considered. There are available a wide variety of electrically powered wheelchair loading devices for the manual folding wheelchair that will assist with storage in or on top of an automobile. However, their effectiveness can be negated by a chair that does not fold to a sufficient degree. If you add to this the number of clients who are now receiving triwheelers and other electric mobility devices, it becomes apparent that for many a modified van is the vehicle of choice.
Vans modified with a fully automatic door opening and a lift, or in the case of a lowered-floor mini van, a ramp, are becoming more and more popular. These van conversions allow easy access to the vehicle and the driving compartment. These conversions are, however, extremely expensive. Driving equipment, and van conversions are usually not covered by third party payers with the exception of those clients covered by workman's compensation or vocational rehabilitation services. In many cases financial support is only provided if independent transportation will lead to employment. For the individual who is unable to transfer from their WC independently, driving a van from their WC may be the only option available to them. This is the driving population who will reap the greatest benefit from the availability of the wide range of highly technical driving systems currently available. These may range from modification of steering systems that greatly reduce the amount of effort required to maneuver the vehicle, to systems that can be operated with just the use of one partially functioning extremity to accelerate, brake and maneuver the vehicle. The wide range of sophisticated driving systems currently available can best be appreciated with the following case example. Kurt is a 21-year-old young man with a diagnosis of Phocomelia. This is a genetic disorder characterized by the absence of formation of one or more long bones in a person's arms or legs. In Kurt's case, it resulted in an absence of both arms and hands and a shortening of his right leg with his right foot attached directly to his femur. This resulted in a relatively non-functional right lower extremity. He is able to ambulate because of good use of this left lower extremity and a specially constructed prosthetic device which accommodated his partial right lower extremity. As is the case with many persons born without the use of upper extremities, he is quite adept at using his left foot for many functions we normally relegate to our upper extremities. Because of the amount of functional ability he had acquired in his left lower extremity, it was determined during an evaluation by the DRS, that he was able to operate a system commonly referred to as a joystick. This is an electronic system that incorporates gas,
CM. Strano / Work 8 (1997) 261 - 266
brake and steering functions into one upright lever or 'joystick.' While it was designed for use with one upper extremity, it was flexible enough so that with the assistance of the system's manufacturer it was able to be installed on the floor of a van for use with his left foot (Fig. 1). Additionally, all of the controls necessary to operate the accessory controls, such as windshield wipers,
265
lights, and climate controls, were incorporated into a dash-mounted computer control panel. Actual operation of the control panel was through an electric headrest equipped with a head-operated switch. In addition to the operation of the accessory controls computer, the headrest contains the switches to operate horn, and turn signals. Needless to say, a system with this level of
Fig. 1. Foot controlled driving system.
266
CM. Strano / Work 8 (1997) 261 -266
sophistication requires a considerable number of hours of training before the client is proficient in its' use. In considering any van modification the actual changes to the structure of the vehicle itself are of great concern to the DRS. With the exception of the work done by the Society of Automotive Engineers Adaptive Devices Committee, there are few if any regulations governing the extensive modifications that may be necessary to accommodate a WC driver in a vehicle. Most DRSs look to this agency for guidelines in recommending van structural modifications (SAE 11725, 1995), and for hand control (SAE 11903, 1990) and WC lift operation and installation (SAE J2093, 1995). Since most of the individuals who will require extensive vehicle modification in order to drive are doing so from their WC, the method of securing the WC to the vehicle structure is of utmost importance (SAE J2249, 1996). For the individual driving from a WC, height in the driving compartment, location of driving controls and access to same become critical. Last but not the least, an important aspect of a driving assessment is the final evaluation or checkout of recommended driving equipment. This may be performed after any vehicle conversion but is more likely to be required after an extensive van modification. This check-out provides the DRS with the opportunity to ensure that the equipment, as ordered, has been provided and that the client is able to operate it in it's current configuration. 3. Conclusion
Driving is a privilege that most of us take for granted. Independent transportation can greatly enhance the opportunities available for employment for the person with a disability. However, driving is a privilege and, unfortunately, it may not be possible for every individual with a physical impairment to accomplish this complex and often costly task. The driving task should be
viewed as an integrated system which encompasses the individual's physical and mental capabilities as well as the availability of the driving equipment. It is highly recommended that persons who have a physical disability receive a thorough driver's evaluation prior to the installation of any driving equipment in their vehicle. It is the responsibility of the DRS to ensure that the driver with a disability is as competent to drive as their non-disabled counterpoint and that any equipment recommended meets currently accepted manufacturing and installation standards. References
Cassis, B. (1984) Dictionary of Eye Tenninology. Gainesville, FL: Tread Publishing. Davidoff, G., Thomas, P., Johnson, M., Dijkers, M., Berent, S., and Doljanac, R. (1988) Closed head injury in acute traumatic spinal cord injury: incidence and risk factors. Arch. Phys. Med. Rehabil. 69, 869-871. Diamond, S. (1959) Ocular evaluation of the cerebral palsied child. Am. J. Ophthalmol. 59, 721-730. Regan, D., Silver, R., and Murray, T.F. (1977) Visual acuity and contrast sensitivity in multiple scherosis - hidden visual loss: an auxiliary diagnostic test. Brain 100,563-579. Society of Automotive Engineers, 11725 (1995) Structural Modifications for Personally Licensed Vehicles to Meet the Transportation Needs of Persons with Disabilities. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. Society of Automotive Engineers, 11903, 1990. Automotive Adaptive Driver Controls, Manual. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. Society of Automotive Engineers, 12093, 1995. Design Considerations for Wheelchair Lifts for Entry to or Exit from a Personally Licensed Vehicle. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. SAE 12249 (1996) Wheelchair Tiedowns and Occupant Restraints for Use in Motor Vehicles. SAE. 400 Commonwealth Drive, Warrendale, PA 15096-0001. Wylie, E.J. (1978) Vision and Driving. Canad. J. Optometry 40,70-74. van Zomeren, A.H., Brouwer, W.H. and Minderhoud, J.M. (1987) Acquired Brain Damage and Driving: A Review. Arch. Phys. Med. Rehabil. 68, 697-705.
