以雷射距離檢測儀量化肱骨頭前向位移之測試信度

Background and Purpose: Glenohumeral joint (GHJ) in stability is defined as inability to maintain the humeral head centered in the glenoid fossa. Accurate noninvasive c1inical tests for shoulder instability are important in clinical assessment and treatment planning for GHJ instability. However, manual tests for assessment of GHJ in stability often lack sound reliability. The purpose of this study was to determine intra-rater reliability of the humeral head anterior translation using a laser displacement meter and fixed displacement force. Methods: We recruited 15 healthy subjects and measured their humeral head anterior translation distance using a laser displacement meter that was known to have high accuracy. A hand-held dynamometer was used to quantify the manual force in displacing the humeral head. Subjects were tested their humeral head anterior translation 5 times on two separate days to determine within-day and between-day intra-rater reliability. Intraclass correlation coefficients (ICC) and standard error of measurements (SEM) were calculated to estimate intra-rater reliability and testing accuracy. Results: The average anterior translation of the humeral head for these subjects were 10.6-10.9 mm when applying a displacement force of 4 pounds and 13-13.9 mm when applying a force of 6 pounds during the tests. Good to excellent within-day and between-day reliabilities, with the ICC values between 0.86 and 0.98 in the 4-pound tests and 0.88-0.95 in the 6-pound tests. The SEM values were between 0.62-0.87 mm for the 4-pound tests and 0.8-1.2 mm for the 6-pound tests. Conclusions: The study has established measurement reliability in quantifying humeral head anterior displacement using a laser distance meter and a hand-held dynamometer. Clinical Relevance: An objective, quantitative, and highly reliable test like this could help clinicians to accurately assess subjects with shoulder instability or laxity and monitor their progress after neuromuscular stabilization training.