Reliability, precision, and gender differences in knee internal/external rotation proprioception measurements.

OBJECTIVE

To develop and assess the reliability and precision of knee internal/external rotation (IR/ER) threshold to detect passive motion (TTDPM) and determine if gender differences exist.

DESIGN

Test-retest for the reliability/precision and cross-sectional for gender comparisons.

SETTING

University neuromuscular and human performance research laboratory.

PARTICIPANTS

Ten subjects for the reliability and precision aim. Twenty subjects (10 males and 10 females) for gender comparisons.

INTERVENTION

All TTDPM tests were performed using a multi-mode dynamometer. Subjects performed TTDPM at two knee positions (near IR or ER end-range). Intraclass correlation coefficient (ICC (3,k)) and standard error of measurement (SEM) were used to evaluate the reliability and precision. Independent t-tests were used to compare genders.

MAIN OUTCOME MEASUREMENTS

TTDPM toward IR and ER at two knee positions.

RESULTS

Intrasession and intersession reliability and precision were good (ICC=0.68-0.86; SEM=0.22°-0.37°). Females had significantly diminished TTDPM toward IR at IR-test position (males: 0.77°±0.14°, females: 1.18°±0.46°, p=0.021) and TTDPM toward IR at the ER-test position (males: 0.87°±0.13°, females: 1.36°±0.58°, p=0.026). No other significant gender differences were found (p>0.05).

CONCLUSIONS

The current IR/ER TTDPM methods are reliable and accurate for the test-retest or cross-section research design. Gender differences were found toward IR where the ACL acts as the secondary restraint.