On the first day after total knee arthroplasty, a therapist uses a continuous passive motion device set from 0° to 40°. The most appropriate reason for using a CPM device is to:

On the first day after total knee arthroplasty, a therapist uses a continuous passive motion device set from 0° to 40°. The most appropriate reason for using a CPM device is to:

• A. To decrease length of hospital stay
• B. To help regain knee flexion
• C. To decrease incidence of deep vein thrombosis
• D. To prevent knee flexion contracture

Answer: (B)

Early knee motion after total knee arthroplasty is used to prevent stiffness by gradually restoring range of motion. The continuous passive motion device moves the knee through a gentle arc without requiring active muscle effort, starting from full extension (0°) toward flexion (40° on day one). This targeted motion helps stretch the joint’s soft tissues, reduce scar tissue formation, and make it easier to regain bend later in the rehabilitation process. While maintaining ROM and preventing contracture are related goals, the primary purpose of using CPM immediately after surgery is to facilitate the restoration of knee flexion. It’s not primarily aimed at shortening hospital stay or preventing deep vein thrombosis.

Early knee motion after total knee arthroplasty is used to prevent stiffness by gradually restoring range of motion. The continuous passive motion device moves the knee through a gentle arc without requiring active muscle effort, starting from full extension (0°) toward flexion (40° on day one). This targeted motion helps stretch the joint’s soft tissues, reduce scar tissue formation, and make it easier to regain bend later in the rehabilitation process. While maintaining ROM and preventing contracture are related goals, the primary purpose of using CPM immediately after surgery is to facilitate the restoration of knee flexion. It’s not primarily aimed at shortening hospital stay or preventing deep vein thrombosis.