title: Intra-rater reliability of ultrasound imaging of wrist extensor muscles in patients with tetraplegia.
abstract: OBJECTIVE
  (i) To determine the intra-rater reliability and precision of the ultrasound cross-sectional area (CSA) measurements of the wrist extensors in individuals with spinal cord injury (SCI), and (ii) to determine whether tetraplegia has a negative influence on the reliability and precision for these measurements.
  
  
  METHODS
  A repeated-measures cross-sectional study.
  
  
  METHODS
  Clinical hospital and academic settings.
  
  
  METHODS
  The study was conducted with 20 men with SCI (9 paraplegia and 11 tetraplegia) and 10 able-bodied controls. Ultrasound images were captured of the right side extensor carpi radialis-longus (ECRL) and the extensor digitorum communis (EDC) were captured in 2 sessions separated by 48-72 hours.
  
  
  RESULTS
  The intraclass correlation coefficients for the CSA measurements of the ECRL and EDC muscles were greater than 0.87 for all 3 groups. The standard error of the measure (SEM) ranged from 0.11-0.22 cm(2) for the ECRL and 0.13-0.27 cm(2) for the EDC. The minimal detectable change of ECL ranged from 0.16 to 0.31 cm(2) and of EDC from 0.19 to 0.38 cm(2). The group differences in muscle CSA of both muscles were found; these differences were greater than the calculated minimal detectable changes. The intraclass correlation coefficients were lower and the SEMs and minimal detectable changes were higher for the group with tetraplegia compared with the able-bodied controls and the group with paraplegia.
  
  
  CONCLUSIONS
  This study documented substantial intra-rater reliability of measurements of the ECRL and ECD CSA by using ultrasound images, which support the use of this technique to effectively evaluate the musculoskeletal changes after SCI and during rehabilitation. Skeletal muscle atrophy in persons with tetraplegia might have a negative influence on the reliability and precision of these CSA measurements; however, these differences in reliability and precision are not of clinical significance.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA; Spinal Cord Injury and Disorders Service, Department of Veterans Affairs Medical Center, Hunter Holmes McGuire Medical Center, 1201 Broad Rock Boulevard, Richmond, VA 23249(∗). Electronic address: ashraf.gorgey@va.gov.
authors.forename: Ashraf S
authors.initials: AS
authors.lastname: Gorgey
authors.affiliation: Physical Medicine and Rehabilitation, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA; Division of Physical Therapy, Virginia Commonwealth University, Richmond, VA(†).
authors.forename: Mark K
authors.initials: MK
authors.lastname: Timmons
authors.affiliation: Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA; Division of Physical Therapy, Virginia Commonwealth University, Richmond, VA(‡).
authors.forename: Lori A
authors.initials: LA
authors.lastname: Michener
authors.affiliation: Physical Medicine and Rehabilitation, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA; Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA(§).
authors.forename: Jeffery J
authors.initials: JJ
authors.lastname: Ericksen
authors.affiliation: Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA; Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA(‖).
authors.forename: David R
authors.initials: DR
authors.lastname: Gater
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging*; D011782:Quadriplegia / Q000209:etiology* / Q000503:physiopathology*; D015203:Reproducibility of Results; D013119:Spinal Cord Injuries / Q000150:complications* / Q000503:physiopathology*; D014463:Ultrasonography; D014953:Wrist / Q000000981:diagnostic imaging*