Power Wheelchair Joystick Use in Spastic Cerebral Palsy

• ClinicalTrials.gov Identifier: NCT00337688
• Recruitment Status: Completed
• First Posted: June 16, 2006
• Last Update Posted: September 14, 2011
• Sponsor: University of Pittsburgh
• Collaborator: Human Engineering Research Laboratories
• Information provided by (Responsible Party): University of Pittsburgh

Study Description

Brief Summary:

There are over 750,000 individuals in the U.S. with Cerebral Palsy (CP). Up to 46% of adults with CP report limited mobility in their communities. However, upper limb spasticity and problems with movement can make the independent use of a wheelchair difficult. Forty percent of individuals who desire mobility via electric wheelchairs are precluded from using them because of problems with upper limb function. No studies to date have produced devices that definitively improve mobility for these individuals. We will recruit 22 subjects with Spastic CP and 22 age and gender matched control subjects without apparent disability from advertisements, mailings, and outpatient clinics. Both a conventional joystick (MSJ) and a novel joystick that is customized for each subject will each be used six different computer screen tasks that simulate driving a wheelchair on a path. We will compare subjects and joysticks based on driving performance. Understanding problems with driving will help us to design joysticks and other assistive devices, not only for CP but for Traumatic Brain Injury, Spinal Cord Injury, Parkinson's Disease, stroke, or a variety of other disabilities.

Condition or disease	Intervention/treatment
Cerebral Palsy; Spasticity	Device: isometric joystick

Detailed Description:

There are over 750,000 individuals in the U.S. with Cerebral Palsy (CP). Up to 46% of adults with CP report limited mobility in their communities. However, upper limb spasticity and motor control impairment can make the independent use of a wheelchair difficult. Forty percent of individuals who desire mobility via electric wheelchairs are precluded from using them because of problems with upper limb function including motor, sensory, or cognitive impairments that can make the use of a conventional joystick difficult. No studies to date have produced devices that definitively improve mobility for these individuals. We will recruit 22 subjects with Spastic CP and 22 age and gender matched control subjects without apparent disability from advertisements, mailings, and outpatient clinics. Both a conventional motion sensing joystick (MSJ) and a novel isometric joystick that is customized for each subject will each be used to maneuver a sprite on a computer screen in six different tasks. Each task involves a path with 90-degree turns. Two tasks have paths that are completely visible to the subject, while four have paths that appear either immediately or at 1, 2, or 3 seconds ahead of the sprite. Because subjects with CP and control subjects are likely to drive at different speeds, subjects will drive under conditions of freely chosen speed and with speed controlled at 1.2 m/s. Joystick input signals that represent the sprite's velocity and position will be recorded. Changes in direction and speed, average deviation from path center, number of boundary violations, start and stop reaction times, response times to turns, and duration of subject movement will be calculated. We will use a Repeated Measures design, treating speed as a covariate under the condition when it is freely chosen. We hypothesize that, regardless of joystick or speed condition, subjects with Spastic CP will have more direction and speed changes, greater average deviation from path center, more boundary violations, prolonged reaction times and response times to turns, and prolonged subject movement time compared to controls. We hypothesize that, regardless of joystick or speed condition, decreasing warning time before turns will be correlated with more direction and speed changes, greater average deviation from path center, more boundary violations, and prolonged subject movement time and that the magnitude of these changes will be greater for those with Spastic CP. We hypothesize that, regardless of speed condition, subjects with Spastic CP, when using a MSJ compared to the isometric joystick, will have more direction and speed changes, greater average path deviation, more boundary violations, and prolonged subject movement. Understanding driving task deficits and warning time for movement decisions will help to identify customization parameters for joysticks and other assistive devices, not only for CP but for Traumatic Brain Injury, Spinal Cord Injury, Parkinson's Disease, stroke, or a variety of other disabilities.

Study Design

• Study Type: Observational
• Actual Enrollment: 50 participants
• Observational Model: Case-Control
• Time Perspective: Prospective
• Official Title: Joystick Use for Virtual Electric Power Wheelchair Driving in Individuals With Spastic Cerebral Palsy
• Study Start Date: July 2006
• Actual Primary Completion Date: June 2008
• Actual Study Completion Date: June 2008

Groups and Cohorts

Intervention Details:

• Device: isometric joystick
  isometric joystick

Outcome Measures

Eligibility Criteria

• Ages Eligible for Study: 12 Years to 80 Years (Child, Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes
• Sampling Method: Non-Probability Sample

Study Population

subjects with CP and controls

Criteria

Inclusion criteria:

1. subjects must be between the ages of 12-80
2. subjects must be able to give written informed consent or consent by proxy to participate
3. subjects with the diagnosis of CP must have a score of 2 or 3 on the Modified Ashworth Scale in at least one of the following in the operating limb: wrist flexors, wrist extensors, elbow flexors, or elbow extensors
4. control subjects must have a Modified Ashworth score of 0 for all of the above muscle groups in both upper limbs
5. subjects must have the minimal motor ability necessary to participate in the trial. This will be measured as follows: after 3 trials, subjects must be able to complete a basic virtual driving with an average minimum speed of no less than 1.2 m/s, an average trial time of no more than 18 seconds, and an average deviation of the center of the virtual wheelchair of no more than 1.5 m from the path center, for each of the two joysticks used. These values are derived from Americans with Disabilities Act (ADA) standard dimensions and human walking speed.

Exclusion Criteria:

1. subjects who are not able to tolerate sitting for 2 hours (the estimated length of the experiment)
2. subjects who have active pelvic or thigh wounds (they may be worsened by prolonged sitting)
3. subjects with a history of seizures in the last 90 days (uncontrolled seizures may be induced by a computer screen task)

Contacts and Locations

Sponsors and Collaborators

University of Pittsburgh

Human Engineering Research Laboratories

Investigators

• Principal Investigator: Brad Dicianno, MD; Human Engineering Research Laboratories

More Information

Additional Information:

Related Info 

• Responsible Party: University of Pittsburgh
• ClinicalTrials.gov Identifier: NCT00337688
• Other Study ID Numbers: 0512006
• First Posted: June 16, 2006
• Last Update Posted: September 14, 2011
• Last Verified: September 2011

Keywords provided by University of Pittsburgh:

Cerebral Palsy; Spasticity; Joystick; Wheelchair; rehabilitation

Additional relevant MeSH terms:

Muscle Spasticity; Paralysis; Cerebral Palsy; Neurologic Manifestations; Nervous System Diseases; Brain Damage, Chronic; Brain Diseases; Central Nervous System Diseases; Muscular Diseases; Musculoskeletal Diseases; Muscle Hypertonia; Neuromuscular Manifestations