The purpose of this study was to determine if a difference exists in the reproducibility of knee joint flexion angles in an open versus a closed kinetic chain. Thirty generally healthy subjects (12 males, 18 females; mean age 23.8 years) participated. Subjects actively reproduced small, medium, and large knee flexion angles (with target angles of 15°, 45°, and 75°, respectively) in an open and a closed kinetic chain while being videotaped. Goniometric measurements were taken from the videotape of initial and reproduced joint angles. Data were analyzed using ANOVA with repeated measures on kinetic chain test position and joint angle. Subjects more accurately reproduced knee flexion angles in a closed kinetic chain position. The main effect for angle and the interaction of angle and test position were nonsignificant. The results indicate that knee joint position is more accurately reproduced in closed kinetic chain. Closed kinetic chain testing is also a more functional assessment of joint position sense, and thus closed kinetic chain assessment of lower extremity joint position sense is recommended.
Susan B. Andersen and Donna M. Terwilliger were graduate students at the School of Physical Therapy, Slippery Rock University, at the time of this study. Andersen is now with The South Side Hospital, 2000 Mary St., Pittsburgh, PA 15203. Terwilliger is now with Westmoreland Regional Hospital, 532 W. Pittsburgh St., Greensburg, PA 15601. Craig R. Denegar is with the School of Physical Therapy, Slippery Rock University, Slippery Rock, PA 16057.