title: Driving with an arm immobilized in a splint: a randomized higher-order crossover trial.
abstract: BACKGROUND
  The aim of this study was to determine whether immobilization of an arm has detrimental effects on driving performance.
  
  
  METHODS
  Thirty-six healthy officers-in-training were assigned a sequence of fiberglass splints (left and right-sided above-the-elbow thumb spica and below-the-elbow splints) with use of a randomized higher-order crossover design. Runs were scored on a cone-marked driving course used for officer certification with predetermined passing requirements. Driving time, the number of cones hit per course section, and the cone-adjusted total time (a five-second penalty per hit cone) were recorded. A linear mixed-effect model with random environmental and learning effects for cone-adjusted time analysis was used. Participants rated perceived driving difficulty and safety with each splint, and ratings were compared with the Wilcoxon signed-rank test.
  
  
  RESULTS
  Thirty participants completed the entire set of runs. Analysis of total cone-adjusted time revealed a significant performance decrease with the left arm in an above-the-elbow thumb spica splint (average, 22.2 seconds; p < 0.001) and with the left arm in a below-the-elbow splint (average, 16.2; p = 0.007). Analysis of forward-only course sections revealed poorer performance trends with all splints, with the worst performance with the left arm in an above-the-elbow thumb spica splint. Driving with the left arm in an above-the-elbow thumb spica splint had the highest perceived difficulty (median, 8.0) and lowest perceived safety (median, 3.0).
  
  
  CONCLUSIONS
  Driving performance as measured with a standardized track and scoring system was significantly degraded with splint immobilization of the left arm. Further studies are required to determine the effect of arm immobilization on normal driving conditions.
authors.affiliation: Vanderbilt Orthopaedic Institute, Vanderbilt University Medical Center, Medical Center East, South Tower, Suites 4200, 1215 21st Avenue South, Nashville, TN 37232, USA.
authors.forename: Paul Y
authors.initials: PY
authors.lastname: Chong
authors.forename: Elizabeth A S
authors.initials: EA
authors.lastname: Koehler
authors.forename: Yu
authors.initials: Y
authors.lastname: Shyr
authors.forename: Jeffry T
authors.initials: JT
authors.lastname: Watson
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Weikert
authors.forename: Justin H
authors.initials: JH
authors.lastname: Rowland
authors.forename: Donald H
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000328:Adult; D001132:Arm; D001334:Automobile Driving; D018592:Cross-Over Studies; D006801:Humans; D007103:Immobilization; D016014:Linear Models; D013165:Splints; D018709:Statistics, Nonparametric; D013647:Task Performance and Analysis