title: Effects of an exercise program to increase hip abductor muscle strength and improve lateral stability following stroke: a single subject design.
abstract: OBJECTIVE
  Persons with lower extremity weakness following stroke often demonstrate difficulty with weight transfer and paretic lower extremity loading. These deficits, in turn, can lead to problems with lateral stability, or the ability to control movement of the center of mass in the frontal plane. The primary aim of this study was to examine the efficacy of an individualized home exercise program in improving hip abductor muscle strength and lateral stability in a subject with chronic stroke.
  
  
  METHODS
  An A-B-A treatment-withdrawal single-subject design was used. The subject was a 70-year-old male who had experienced a left hemispheric stroke 36 months prior to initiation of the study. Bilateral hip abductor muscle strength, single limb stance (SLS), timed 360 degrees turn, Step Test, and 10-m walk at self-selected and fast speeds were recorded at regular intervals during the baseline (A-I), treatment (B), and treatment-withdrawal (A-2) phases. The home exercise program in the B phase consisted of lower extremity weight bearing and weight transfer activities and exercise on a lateral training device 3 to 5 times a week for 6 weeks. The Berg Balance Scale (BBS) and Stroke Impact Scale (SIS) were administered at the completion of each phase and at 6-week follow-up. Data were analyzed using visual analysis and the split-middle method of trend estimation.
  
  
  RESULTS
  Mean levels of all measures improved from A-1 to B phases, with significant increases in trend for hip abductor muscle strength and SLS bilaterally. Most improvements were maintained during the treatment-withdrawal (A-2) phase and at follow-up.
  
  
  CONCLUSIONS
  A home exercise program that includes exercise on a lateral training device shows promise for producing increases in hip abductor muscle strength and accompanying improvements in some measures of physical performance and disability in persons with chronic stroke.
authors.affiliation: Center for Human Movement Science, Division of Physical Therapy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7135, USA. vmercer@med.unc.edu
authors.forename: Vicki S
authors.initials: VS
authors.lastname: Mercer
authors.forename: Shuo-Hsiu
authors.initials: SH
authors.lastname: Chang
authors.forename: Cherie D
authors.initials: CD
authors.lastname: Williams
authors.forename: Kelli
authors.initials: K
authors.lastname: Noble
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Vance
mesh_terms: D000368:Aged; D005081:Exercise Therapy / Q000379:methods*; D006801:Humans; D008297:Male; D018908:Muscle Weakness / Q000534:rehabilitation*; D018482:Muscle, Skeletal; D010291:Paresis / Q000534:rehabilitation*; D004856:Postural Balance; D020127:Recovery of Function; D000071939:Stroke Rehabilitation; D016138:Walking