The use of real-time ultrasound feedback in teaching abdominal hollowing exercises to healthy subjects.
METHODS
Randomized controlled trial.


OBJECTIVE
To determine if supplementing typical clinical instruction with real-time ultrasound feedback facilitates performance and retention of the abdominal hollowing exercise (AHE).


BACKGROUND
Increasingly clinicians are using real-time ultrasound imaging as a form of feedback when teaching patients trunk stabilization exercises; however, there has been no justification for this practice.


METHODS
Forty-eight subjects were divided randomly into 3 groups that received different types of feedback: group 1 received minimal verbal feedback, group 2 received verbal and palpatory feedback, and group 3 received real-time ultrasound, verbal, and palpatory feedback. If the subject performed 3 consecutive correct AHEs during the initial session, she/he returned for a retention test. The performance of 3 consecutive, correct AHEs was the criterion measure; the number of trials to criterion was also recorded during the initial and retention test sessions.


RESULTS
The ability to perform the AHE differed among groups (P<.001). During the initial session, 12.5% of subjects in group 1, 50.0% of subjects in group 2, and 87.5% of subjects in group 3 were able to perform 3 consecutive AHEs. Group 3 subjects achieved the criterion in fewer trials than the other 2 groups (P = .0006). No differences among groups were found for the retention testing; however, low power due to fewer subjects precluded a strong interpretation of this finding.


CONCLUSIONS
Real-time ultrasound feedback can decrease the number of trials needed to consistently perform the AHE; however, the data are inconclusive with regard to retention of this skill.
Department of Physical Therapy, University of Vermont, Burlington, VT 05405-0068, USA. sharon.henry@uvm.edu
Sharon M
SM
Henry
Karen C
KC
Westervelt
D000009:Abdominal Muscles / Q000000981:diagnostic imaging*; D000293:Adolescent; D000328:Adult; D001676:Biofeedback, Psychology; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D007721:Knowledge of Results, Psychological; D008297:Male; D008875:Middle Aged; D013647:Task Performance and Analysis; D013663:Teaching; D014463:Ultrasonography