Isokinetic training and muscle torque measurements are commonly used d
uring rehabilitation after knee ligament injuries. Isokinetic maximal
muscle strength tests are performed to monitor the progress in muscle
rehabilitation. The muscle power is evaluated by measuring the applied
force in the direction of motion (concentric muscle power) or the for
ce against the direction of motion (eccentric muscle power). Both legs
are examined to compare the total muscle work and peak torques of the
involved leg with those of the uninvolved leg. We report the case of
an acute patellar dislocation during eccentric testing of the uninvolv
ed leg on the Biodex isokinetic dynamometer testing device (Biodex Cor
poration, Shirley, NY).