Return to driving after lower-extremity amputation

OBJECTIVES: To study driving behaviors after major lower-extremity amputations and to determine which factors influence return to driving after amputation. DESIGN: A cross-sectional study. SETTING: Data were collected from patients attending an outpatient amputee and prosthetics clinic between February 2001 and September 2001. PARTICIPANTS: A convenience sample (N=123). Inclusion criteria were: age greater than 18 years, unilateral or bilateral major lower-extremity amputation, minimum 1 year since prosthetic fitting, and active automobile driver within 6 months prior to amputation. Subjects had an average age of 63.4+/-12.1 years and were on average 6.8+/-8.3 years since amputation. Common causes for amputation were peripheral vascular disease (73.2%), trauma (13.8%), and tumor (12.2%). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Driving habits after lower-extremity amputation. RESULTS: Overall, 80.5% of participants were able to return to driving an average of 3.8 months after amputation, although the majority reported a decreased driving frequency. Female sex (odds ratio [OR]=.08; 95% confidence interval [CI], .02-.34), age of 60 years or greater (OR=.16; 95% CI, .03-.74), right-sided amputation (OR=.13; 95% CI, .03-.52), and preamputation driving frequency of less than every day (OR=.18; 95% CI, .05-.69) were all significantly related to a reduced likelihood of return to driving postamputation. Items that did not have a statistically significant association with return to driving included level of amputation, reason for amputation, preamputation automobile transmission, and accessibility to public transit. Subjects with left-sided amputation had significantly fewer concerns about driving, while those with a right amputation frequently required vehicle modifications (40.6%) or switch to a left-foot driving style for braking (81.3%) and accelerating (65.6%). Common barriers to return to driving included preference not to drive, fear and/or lack of confidence, and related medical conditions. CONCLUSIONS: The majority of subjects with major lower-extremity amputation were able to return to driving after major lower-extremity amputation. Major automobile modifications are commonly performed by right-sided amputees. Several predictors of return to driving and barriers preventing return to driving were identified.     

The effects of task complexity on brake response time before and after primary right total knee arthroplasty

Marques CJ, Cabri J, Barreiros J, Carita AI, Friesecke C, Loehr JF. The effects of task complexity on brake response time before and after primary right total knee arthroplasty.

Objective

To study the effects of an increase in task complexity on brake response time (BRT) in patients undergoing total knee arthroplasty (TKA).

Design

A prospective repeated-measures design was used. The measurements took place 1 day before and 10 and 30 days after surgery.

Setting

Clinic.

Participants

The data of patients (N=21) who were admitted for primary total arthroplasty of the right knee were pooled for analysis.

Interventions

On each measurement day patients performed 5 practice and 10 test trials for 2 tasks (1 simple, 1 complex) in a car simulator. Task complexity was increased by adding a second movement to the first task performed.

Main Outcome Measures

BRT, reaction time (RT), and movement time were assessed.

Results

An increase in task complexity increased BRT, RT, and movement time at all measurement times. Right TKA increased BRT by increasing movement time. Thirty days after surgery BRT was no longer increased compared with preoperative values in both tasks.

Conclusions

Task complexity consistently increased BRT and its components. The effects of task complexity remained constant throughout the 3 measurements. After right TKA, we suggest patients should be advised to wait 30 days after surgery before resuming driving.     

Driving and community integration after traumatic brain injury

Rapport LJ, Coleman Bryer R, Hanks RA. Driving and community integration after traumatic brain injury.

Objective

To examine resumption of driving after traumatic brain injury (TBI) and its relation to community integration.

Design

Cross-sectional cohort study; survey and cognitive data.

Settings

Inpatient rehabilitation hospital of the Traumatic Brain Injury Model Systems and community.

Participants

Persons (N=261) ranging from 3 months to 15 years postinjury.

Interventions

Not applicable.

Main Outcome Measures

Barriers to Driving Questionnaire, Driver Survey, Community Integration Measure, and Craig Hospital Assessment and Reporting Technique.

Results

Forty-four percent of survivors had resumed driving; of nondrivers, 48% reported a strong desire to resume driving. Nondriver survivors who sought to resume driving generally rated themselves as currently fit to drive, viewed themselves as having physical and cognitive profiles like those of survivor drivers, and reported their greatest barriers to driving as social and resource related. However, cognitive functioning was similar to nondriver survivors who did not seek to resume driving and significantly worse than survivors who were currently driving. Nondrivers showed poorer community integration than did drivers, even after accounting for injury severity, social support, negative affectivity, and use of alternative transportation. Use of alternative transportation was common among nondrivers, but it was unrelated to community integration outcomes. Cognitive functioning moderated risk of adverse incident: among survivors with low cognitive functioning and high self-estimates of driving ability, which is indicative of unawareness of deficit, adverse incidents showed positive relation to amount of driving and inverse relation to cognitive functioning.

Conclusions

Driving status has unique and independent association with post-TBI community integration. Additional research is needed to evaluate transportation barriers that undermine full engagement in community living after TBI and to determine which barriers to driving reflect valid risk to survivors and the public.     

Six-minute walk test in persons with transtibial amputation

Lin S-J, Bose NH. Six-minute walk test in persons with transtibial amputation.

Objective

This study was to report the within-day test-retest reliability and the measurement properties of the six-minute walk test (6MWT) in persons with lower-limb (transtibial) amputation.

Design

Test-retest study design.

Setting

University research laboratory.

Participants

Subjects (N=13) with transtibial amputation (9 men and 4 women; mean age, 46y).

Interventions

Three trials of the 6MWT were conducted within 1 day with 20 to 30 minutes of rest between consecutive trials. Timed Up & Go (TUG) test and timed one-leg balance tests were conducted on another day.

Main Outcome Measures

(1) Distance, heart rate, symptoms and signs of exercise intolerance during the walk test, (2) times of the TUG test and the one-leg balance test.

Results

The intraclass correlation coefficient (ICC_3,1) value was .94. Bland and Altman graphs showed no systemic variations between trials and a small learning effect. The peak heart rate approximated 72% to 78% of the age-predicted maximal heart rate. Moderate degrees of correlation were observed in: (1) the 6MWT versus the TUG test (r=–.76, P<.05), and (2) the 6MWT versus the timed prosthetic-leg stance (with eyes open: r=.63, P<.05; with eyes closed: r=.61, P<.05).

Conclusions

These findings suggest that the 6MWT could be considered as a reliable measure of functional capacity, involves a moderate degree of exercise intensity, and is related in a moderate degree to postural control abilities in persons with transtibial amputation.     

Houghton Scale of prosthetic use in people with lower-extremity amputations: Reliability, validity, and responsiveness to change

OBJECTIVE: To evaluate the responsiveness to change and the floor and ceiling effects of the Houghton Scale. DESIGN: One-week and 3-month test-retest to evaluate reliability, validity, and responsiveness to change. SETTING: Amputee rehabilitation program. PARTICIPANTS: Persons (N=125) with unilateral or bilateral lower-extremity amputation who were wearing a prostheses: 1 group (n=49) for the reliability component and another group (n=76) for the responsiveness and validity component. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Responsiveness to change, ceiling and floor effects, and reliability and convergent validity. RESULTS: Evaluation of responsiveness to change (n=76) showed that the total score increased from a mean +/- standard deviation of 6.14+/-2.40 at discharge to 7.70+/-2.62 (P<.001) at follow-up 3 months later. Floor and ceiling effects were not detected for the overall score but were noted for the individual subscales. The internal consistency was moderate at discharge (Cronbach alpha=.71) and follow-up (Cronbach alpha=.70). The Houghton Scale correlated significantly, although moderately, with the physical composite score of the Medical Outcomes Study 36-Item Short-Form Health Survey (r=.393, P<.01) and the 2-minute walk test at admission (r=.620, P<.01) and discharge (r=.653, P<.01). The reliability (intraclass correlation coefficient=.96) of the Houghton Scale was high (n=49). CONCLUSIONS: The Houghton Scale is appropriately responsive to change in prosthetic use in individuals with lower-limb amputation after rehabilitation.     

Clinical identification of multiple fall risk early after unilateral transtibial amputation

OBJECTIVE: To examine if previously reported clinical tests of stepping and functional mobility could discriminate between multiple-falling and nonmultiple-falling people with unilateral transtibial amputations. DESIGN: Nonrandomized prospective cohort. SETTING: Rehabilitation hospital and general community. PARTICIPANTS: Forty-seven subjects initially recruited and tested at discharge. Forty subjects were retested at 6 months postdischarge and grouped as either multiple fallers (n=13) or nonmultiple fallers (n=27). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Four Square Step Test (FSST), Timed Up & Go (TUG) test, 180 degrees turn test, and the Locomotor Capabilities Index (LCI) advanced score. RESULTS: Significant differences (P<.01) were found between the 2 groups for all of the main outcome measures. The test scores associated with an increased risk of having multiple falls were as follows: TUG test of 19 seconds or more (sensitivity, 85%; specificity, 74%), turn time of 3.7 seconds or more (sensitivity, 85%; specificity, 78%), turn steps 6 steps or more (sensitivity, 100%; specificity, 74%), FSST of 24 seconds or more (sensitivity, 92%; specificity, 93%), and LCI advanced score of 15 or less (sensitivity, 43%; specificity, 91%). CONCLUSIONS: In this study, multiple-falling people with transtibial amputations displayed impaired mobility on the outcome measures reported. These measures offer valuable clinical tests of different and functionally relevant activities and provide good identification of multiple-falls risk.     

Discharge destination after dysvascular lower-limb amputations

OBJECTIVE: To examine postacute care rehabilitation services use after dysvascular amputation. DESIGN: State-maintained hospital discharge data from the Maryland Health Services Cost Review Commission were analyzed. SETTING: Maryland statewide hospital discharge database. PARTICIPANTS: Persons discharged from nonfederal acute care hospitals from 1986 to 1997 with a procedure code for lower-limb amputation (ICD-9-CM code 84.12-.19), excluding toe amputations. Those persons with amputations due to trauma, bone malignancy, or congenital anomalies were excluded. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Postacute care service utilization. RESULTS: There were 16,759 discharges with an amputation procedure over this period. The average age was 69.3+/-14.3 years, and 51.9% were men. Black persons comprised 42.4% of the sample. Diabetes was present in 42.0%, and peripheral vascular disease was noted for 66.1% of amputees. Amputations were at the foot (19.4%), transtibial (38.1%), and transfemoral (42.4%) levels. The largest proportion (40.6%) of patients was discharged directly home after acute care, 37.4% went to a nursing home, 9.2% went home with home care, and 9.6% were discharged to an inpatient rehabilitation unit. From 1986 to 1997, there were downward trends in the rate of discharges directly home and corresponding upward trends in nursing home and inpatient rehabilitation dispositions. CONCLUSIONS: Inpatient rehabilitation use is infrequent after dysvascular amputation. Prospective studies are necessary to examine outcomes for persons receiving rehabilitation services in different care settings to define the optimal rehabilitation venue for functional restoration.     

Differences in gait characteristics between persons with bilateral transtibial amputations, due to peripheral vascular disease and trauma, and able-bodied ambulators

Su P-F, Gard SA, Lipschutz RD, Kuiken TA. Differences in gait characteristics between persons with bilateral transtibial amputations, due to peripheral vascular disease and trauma, and able-bodied ambulators.

Objectives

To examine differences in gait characteristics between persons with bilateral transtibial amputations because of trauma and peripheral vascular disease (PVD); and to compare that with data from able-bodied controls that were previously collected and maintained in a laboratory database.

Design

Observational study of persons with bilateral transtibial amputations.

Setting

A motion analysis laboratory.

Participants

Nineteen bilateral transtibial amputees.

Intervention

No experimental intervention was performed. To standardize the effect of prosthetic foot type, subjects were fitted with Seattle Lightfoot II feet 2 weeks before quantitative gait analyses.

Main Outcome Measures

Temporospatial, kinematic, and kinetic gait data were recorded and analyzed.

Results

Results showed that the freely selected walking speeds of subjects with PVD and trauma were 0.69m/s and 1.11m/s, respectively, while that of able-bodied control subjects was 1.20m/s. When data were compared on the basis of freely selected walking speed, numerous differences were found in temporospatial, kinematic, and kinetic parameters between the PVD and trauma groups. However, when data from similar speeds were compared, the temporospatial, kinematic, and kinetic gait data demonstrated no statistically significant differences between the 2 amputee groups. Although not statistically significant, the PVD group displayed increased knee (P=.09) and hip (P=.06) flexion during the swing phase, whereas the trauma group displayed increased pelvic obliquity (P=.06). These actions were believed to represent different strategies to increase swing phase foot clearance. Also, the PVD group exhibited slightly greater hip power (P=.05) before toe-off.

Conclusions

Many of the differences observed in the quantitative gait data between the trauma and PVD groups appeared to be directly associated with their freely selected walking speed; the trauma group walked at significantly faster freely selected speeds than the PVD group. When their walking speeds were matched, both amputee groups displayed similar gait characteristics, with the exception that they might use slightly different strategies to increase foot clearance.     

Vision and Driving in Multiple Sclerosis

Schultheis MT, Manning K, Weisser V, Blasco A, Ang J, Wilkinson ME. Vision and driving in multiple sclerosis.

Objective

To examine the relationship between measures of visual dysfunction and driving performance in persons with multiple sclerosis (MS).

Design

Between-group comparison.

Setting

All data were collected in an outpatient research setting.

Participants

Persons (N=66) with MS of the relapsing remitting type (26 self-reporting visual difficulties; 40 self-reporting no visual difficulties) and 26 age- and sex-matched healthy controls.

Interventions

Not applicable.

Main Outcome Measures

Measures of vision included visual acuity, depth perception, and color perception. Driving was measured using documented accident/violation rate and self-reported driving behaviors.

Results

Quantitative analysis only revealed that MS persons with self-reported visual difficulties performed significantly worse than healthy controls on color perception (Kruskal-Wallis; χ₂²=8.89, P=.01). There were no group differences on driving behaviors, and correlational analysis revealed a lack of relationship between the selected visual (visual acuity, depth perception, color perception) and driving performance measures (documented accident/violation rate and self-limiting driving behaviors).

Conclusions

Persons with MS who self-reported difficulties with vision had acceptable visual acuity, despite demonstrating impairment in color perception. The fact that visual acuity remains the most common measure for visual fitness to drive remains problematic. There is a need to further define measures of visual dysfunction relevant to driving among this clinical population.     

康复训练对脑损伤患儿视觉反应时的影响

目的了解康复训练对脑损伤患儿视觉反应时的影响及其在残疾儿童脑功能评价和康复疗效分析中的作用。方法观察组为51例脑损伤患儿，对照组为29例正常儿童，均进行光刺激的复杂视觉反应时测试，并比较观察组康复训练前、后的反应时成绩。结果观察组训练前各项反应时成绩明显较对照组延长（P〈0．01）。训练后观察组的反应时成绩则明显改善（除左侧第二反应时），第一反应时与对照组差异无统计学意义（P〉0．05）；中度障碍的观察组患儿训练后反应时的改善程度最明显。结论脑损伤患儿注意力和反应速度均有异常，但经过训练后可有明显改善。反应时作为一种简单、易测、灵敏、客观的神经心理活动指标，在残疾儿童高级脑功能评价和康复疗效分析中具有重要意义。     

Examining the Relationship Between Cognition and Driving Performance in Multiple Sclerosis

Schultheis MT, Weisser V, Ang J, Elovic E, Nead R, Sestito N, Fleksher C, Millis SR. Examining the relationship between cognition and driving performance in multiple sclerosis.

Objective

To identify cognitive predictors of driving performance after multiple sclerosis (MS).

Design

Prospective design examining predictive value of cognitive measures on driving performance.

Setting

All data were collected in an outpatient research setting and an outpatient driver rehabilitation program.

Participants

Participants were community-dwelling persons (N=66) with clinically defined MS (86% relapsing-remitting, 14% progressive) with a mean age of 43.47 years. All were active drivers who met vision requirements established by their respective states, and none required adaptive driving equipment.

Intervention

Not applicable.

Main Outcome Measures

Participants were administered a comprehensive neuropsychologic assessment and a clinical behind-the-wheel (BTW) driving evaluation. Additional measures of driving performance included history of traffic violations and collisions (since MS onset).

Results

Logistic regression indicated that information processing speed (Symbol Digit Modality Test [SDMT]) was the strongest predictor of BTW performance. A logistic regression revealed that the strongest predictors of collision and violation frequency were visuospatial learning and recall (7/24 Spatial Recall Test [SPART 7/24]).

Conclusions

These findings indicate that information processing and visuospatial skills are predictive of driving performance among persons with MS. These measures (SDMT and SPART 7/24) may serve as screening methods for identifying the potential impact of cognitive impairment on driving. Furthermore, the findings raise questions regarding the appropriateness of the BTW evaluation to evaluate driving difficulties accurately among individuals with MS.     

Neuropsychological Performance,Brain Imaging,and Driving Violations in Multiple Sclerosis

Objective

To examine the relationship between third ventricular width, a measure of thalamic brain atrophy, and motor vehicle violation type and frequency in a cohort of patients with multiple sclerosis (MS).

Design

Retrospective cohort study.

Setting

Tertiary care university hospital.

Participants

Thirty-five individuals with clinically confirmed relapsing-remitting multiple sclerosis and 35 age-, sex-, and education-matched community-dwelling healthy comparisons (N=70). Participants were aged between 25 and 65 years.

Interventions

Not applicable.

Main Outcome Measures

Data on motor vehicle violations were obtained from an online database (Iowa Courts Online). The violations were categorized as follows: (1) speeding, (2) nonmoving safety, (3) administrative, (4) alcohol-related offense, (5) moving safety, and (6) total violations. Neuropsychological performance in all major cognitive domains was obtained. Thalamic atrophy for the patients with MS was determined via third ventricular width measurement.

Results

The MS group had a greater number of overall violations, administrative violations, and nonmoving safety violations. The groups differed on neuropsychological tasks measuring visuospatial skills, speeded language, learning, and executive functioning, after controlling for affective symptoms. Third ventricular width was associated with total violations as well as moving safety violations. Finally, third ventricular width accounted for a significant variance in driving violation frequency above and beyond demographic variables and neuropsychological factors.

Conclusions

There is an increased frequency of motor vehicle violations among patients with multiple sclerosis, and the number of violations can be predicted by thalamic brain atrophy.     

Adaptations to mass perturbations in transtibial amputees: Kinetic or kinematic invariance?

OBJECTIVE: To establish the adaptation strategy transtibial amputees use after mass perturbation of their prosthetic lower leg. DESIGN: We investigated whether the measured adaptations to mass perturbation of the lower leg in transtibial amputees can better be described as (1) a kinetic invariance strategy in which kinetics (joint torques) remain the same while kinematics (joint angles) change or (2) a kinematic invariance strategy in which kinematics remain the same while kinetics change. SETTING: A gait laboratory. PARTICIPANTS: Ten transtibial amputees. INTERVENTIONS: Five different mass conditions. MAIN OUTCOME MEASURES: Measured joint torques and angles during the swing phase in the different mass conditions. RESULTS: Mass perturbation induced more significant changes and larger effect sizes in joint torques than in joint angles. CONCLUSIONS: Transtibial amputees adapt to mass perturbation primarily by maintaining the same kinematic pattern and adjusting their joint torques, that is, they use a kinematic invariance strategy. This implies that manipulating prosthetic inertial properties does not directly influence gait kinematics and that inertial properties should be evaluated in terms of the energetic cost of the swing phase.     

Patient Factors Associated With Return to Driving Poststroke: Findings From a Multicenter Cohort Study

Perrier M-J, Korner-Bitensky N, Mayo NE. Patient factors associated with return to driving poststroke: findings from a multicenter cohort study.

Objective

To estimate the extent to which body structure, function, activity, and context explain driving resumption at 1 year.

Design

Cohort study with relationships modeled in a path analysis.

Setting

Three urban Canadian communities.

Participants

Patients admitted to hospital with acute stroke who had driven before their stroke (n=290) who participated in a longitudinal study of stroke outcomes.

Main Outcome Measures

Driving resumption 1 year after the initial stroke diagnosis.

Results

One hundred seventy-seven patients (61%) returned to driving after 1 year. Direct relationships were found between measures of strength and motor activity (Stroke Impact Scale), cognition (Mini-Mental State Examination), type of stroke (hemorrhagic vs ischemic), and driving resumption at 1 year. The effects of stroke severity, fatigue, and sex on driving resumption were mediated through strength and motor activity shown by a model that had excellent fit (comparative fit index=.985, Tucker-Lewis Index=.952, root mean square error of approximation=.046).

Conclusions

There are multiple direct and indirect influences on driving resumption at 1 year, from the type of stroke, physical strength and motor activity, cognition, sex, and fatigue measured at 3 months. The paths outlined by this model highlight how stroke sequelae influence community mobility, as well as factors related to driving resumption that are amenable to intervention.     

Influence of Left- and Right-Side Total Hip Arthroplasty on the Ability to Perform an Emergency Stop While Driving a Car

Objective

To show the possible effect of left- and right-side total hip arthroplasty (THA) on the ability to perform an emergency stop when driving a car.

Design

Inception cohort.

Setting

A driving simulator using an actual car cabin, specifically developed for the experiment, was used for testing driving ability.

Participants

Patients (N=40; 20 left-side THA/20 right-side THA) were tested preoperatively and in increments of 8 days and 6, 12, and 52 weeks after surgery.

Interventions

Left- and right-side THA.

Main Outcome Measures

Reaction time, movement time, total brake response time (TBRT), and maximum brake force.

Results

Eight days postoperatively, measurements on driving performance indicated a slight worsening for all outcome parameters in patients after left-side THA and considerably more worsening in patients after right-side THA. For both patient groups, significant improvements in outcome measures were noted during the 1-year follow-up. Brake force declined significantly in patients with left-side THA (P=.012) and in patients after right-side THA (P<.001). A total of 35% of the patients with right-side THA and 15% with left-side THA could not meet the 600ms TBRT threshold 6 weeks postoperatively.

Conclusions

Most patients who underwent right-side THA reached their preoperative baseline 6 weeks after surgery. Most of the patients with left-side THA showed no TBRT limitations 8 days postoperatively. Because of the patients' highly individual rehabilitation course and considering the possible consequences of the premature resumption of driving a motor vehicle, individual examination and recommendation are necessary.