Intrarater reliability of the KT1000 arthrometer in determining anterior translation of the glenohumeral joint.

Objectives: To establish intrarater reliability of the KT1000 arthrometer in determining glenohumeral anterior translation and to determine if a difference existed between measurements of glenohumeral anterior translation in 2 testing positions.

Design: Intrarater reliability study.

Setting: Academic laboratory.

Participants: Convenience sample of 15 unimpaired volunteers (mean age +/- standard deviation, 25+/-4 y).

Interventions: Not applicable.

Main Outcome Measures: Subjects were positioned supine with the shoulder in 20 degrees of abduction and 0 degrees of external rotation (position 1) and 90 degrees of abduction and 90 degrees of external rotation (position 2). The KT1000 was placed on the shoulder with the tibia sensor pad near the joint line and the patella sensor pad over the coracoid process. Testing involved an anteriorly directed force of 67N. Testing procedures were repeated after 1 week.

Results: The intraclass correlation coefficients (ICCs) for intrarater reliability for position 1 (ICC=.93; 95% confidence interval [CI], .81-.98) and for position 2 (ICC=.93; 95% CI, .80-.97) were excellent. The degree of anterior translation measured in position 1 was significantly greater than in position 2 ( t =4.79, P <.01).

Conclusions: Use of the KT1000 to measure glenohumeral anterior translation in the 2 testing positions appears to be a relatively simple, reliable method. Because testing position 1 allowed significantly greater anterior translation than testing position 2, the 2 positions should not be used interchangeably.