Locomotor deficits before and two months after knee arthroplasty

Objectives. To quantify the locomotor deficits before and 2 months after a total knee arthroplasty (TKA) in patients with osteoarthritis of the knee, and to compare pre- and postoperative performance. Methods. Locomotor capacity of patients was evaluated using laboratory gait and stair-ascent evaluations (kinematic and kinetic variables, electromyographic activity of 4 muscles of both lower limbs, and spatiotemporal parameters), the timed Up & Go (TUG), and the 6-minute walk (6MW) test. Results. Large locomotor deficits (increased hip flexion, decreased excursions of the knee and ankle, smaller extensor and flexor moments of force at the 3 joints, and muscle activation levels lower in all muscles tested) are still present in patients, particularly in the single-limb support subphase before and 2 months after TKA. These deficits explain the slower walk and stair-ascent speeds and a reduced performance at the TUG and 6MW tests. Conclusions. These results emphasize the need for more careful followup and intensive rehabilitation programs in the first months following TKA.