DEVELOPMENT OF A RELIABLE METHOD TO CLINICALLY MEASURE HIP ABDUCTION FORCE IN YOUNG AND OLD ADULTS. Paula Click-Fenter*; James W. Bellew; Susan Smith; Jennifer Hauck; Ashley Knecht Physical Therapy, Louisiana State University Health Sciences Center, Shreveport, LA PURPOSE: The purpose of this study was to obtain a reliable hip abduction force production method in adults ages 20-89 using a Jamar Hydraulic Hand Dynamometer [TM](JHHD)(Sammons Preston) and to determine the average force produced by individuals in a wide range of ages. BACKGROUNDS/SIGNIFICANCE: Hip abduction strength plays a key role in gait, pelvic stability and balance. Reliable information about how much force an adult can produce could be used as a guide for measuring rehabilitation goals and outcomes. SUBJECTS: A convenience sample of 160 normal, healthy adults ranging from 20-89 years of age participated. Excluded were individuals who presented with any hip or gait pathology or those who were participating in an active weight exercise program. Prior to being tested, informed consent was obtained. METHODS AND MATERIALS: The subjects were tested in a gravity neutral, supine position on one of 2 portable tables with metal supports. The dynamometeres were mounted on an upright attached to the table and the thigh of each subject was positionned 2 inches proximal to the lateral joint line of the knee on the right thigh. A stabilizing belt was placed across the pelvis to control hip internal or external rotation. Subjects were allowed to use upper extremities for stabilization during testing. Two practice trials were allowed for each subject prior to performing the test. An isometric test was used in which the subject exerted a maximal isometric forace against the dynamometer for 2-4 seconds for 2 trials. A ninety-second rest period was allowed between each trial. Prior to testing, inter-rater and intra-rater reliability were calculated. ANALYSES: Averages for age decade was calculated. Intra-rater reliability and inter-rater reliability were determined for each examiner using the Intraclass Correlation Coefficient (ICC). A paired samples T-test was used to determine if a significant difference existed between the 2 trials. RESULTS: Participants consisted for 45 men and 115 women. Values for hip abduction strength were obtained (measured in Newtons (N) of force)and averaged between the two trials according to age decade. A range of averages was found from 310 N in for men and 187 for women in 20-29 decade; 345 N for men and 190 N for women 30-39 decade; 292 N for men and 170 for women in 40-49 decade; 236 N for men and 157 N for women in the 50-59 decade; 184 N for men and 148 N for women in the 60-69 decade; 213 N for men and 114 N for women in the 70-79 decade; and 75 N for men and 80 N for women in 80-89 decade. Intra-rater and inter-rater reliability were found to be high with an ICC ranging from 0.94-0.97 and 0.95-0.98 respectively. Paired samples T-test found high correlation at 0.938 (p<0.01) between trial 1 and 2. CONCLUSIONS: The values obtained in this study provide a reference of average force production in 7 decades of normal adults that can be used for comparison when hip abduction force is important for the rehabilitation process. FUNDING SOURCE: Equipment was funded through an Intra-mural grant from the School of Allied Health Professions, Louisiana State University health Sciences Center. No gain was realized as a result of the funding to any of the authors. KEYWORDS: hip, abduction, force Copyright 2009 by the American Physical Therapy Association. Requests for reprints should be directed to the corresponding author of the article. Educators, students, and other academic customers may receive permission to reprint copyrighted material from Physical Therapy (ISSN 1538-6724) by contacting the Copyright Clearance Center Inc, 222 Rosewood Dr, Danvers, MA 01923. Other types of customers who want permission to reprint should contact the APTA Editorial Office, Attn: Physical Therapy.