continuous passive motion
Continuous Passive Motion (CPM) therapy uses machines to move a joint passively i.e. without the patient exerting any effort. A motorised device moves the joint repetitively to a set of number of degrees and movement speed, determined by the physiotherapist. CPM machines are most commonly applied to the knee, but there are versions for other joints such as the hip, shoulder and elbow.
Continuous passive motion (CPM) devices are used during
the first phase of rehabilitation following a soft tissue
surgical procedure or trauma. The goals of phase 1
rehabilitation are: control post-operative pain, reduce
inflammation, provide passive motion in a specific plane
of movement, and protect the healing repair or tissue. CPM
is carried out by a CPM device, which constantly moves the
joint through a controlled range of motion; the exact
range is dependent upon the joint, but in most cases the
range of motion is increased over time.
CPM is used following various types of
reconstructive joint surgery such as knee replacement and
ACL reconstruction. Its mechanisms of action for aiding
joint recovery are dependent upon what surgery is
performed. One mechanism is the movement of synovial fluid
to allow for better diffusion of nutrients into damaged
cartilage, and diffusion of other materials out; such as
blood and metabolic waste products. Another mechanism is
the prevention of fibrous scar tissue formation in the
joint, which tends to decrease the range of motion for a
joint.