Physical therapy and rehabilitation often utilize a complex vocabulary, leading to confusion about which specific techniques fit within broader treatment categories. Patients seeking hands-on care frequently encounter terms like “Passive Range of Motion” (PROM) and “Manual Therapy.” Understanding the relationship between these interventions is important for patients to comprehend their treatment plan and establish informed expectations about restoring mobility and function.
What is Passive Range of Motion (PROM)?
Passive Range of Motion (PROM) describes the movement of a joint through its available arc, generated entirely by an external force. This force can come from a therapist’s hands, a continuous passive motion (CPM) machine, or gravity, requiring no muscular effort from the patient. The patient’s muscles surrounding the joint remain completely relaxed during the movement.
The primary purpose of applying PROM is to maintain the existing length of muscles and soft tissues, preserving joint flexibility and mobility. Therapists use PROM to prevent contractures—permanent shortenings of muscle or connective tissue that severely limit movement. PROM also stimulates local circulation and improves the nutrition of the joint’s cartilage by encouraging the movement of synovial fluid.
Defining Manual Therapy in Rehabilitation
Manual therapy is an expansive category of treatment that involves a clinician using their hands to apply skilled, specific forces to the patient’s body. It is defined as a clinical approach that uses hands-on techniques to diagnose and treat soft tissues and joint structures. This method aims to modulate pain, improve tissue extensibility, and enhance overall joint mechanics.
Manual therapy is not a single technique but a collection of highly specialized procedures. Examples include joint mobilization, which uses slow, rhythmic movements to increase joint play, and joint manipulation, which involves a rapid, small-amplitude thrust. Other common hands-on techniques are soft tissue manipulation, such as deep tissue friction and massage, which are used to address muscle tension and fascial restrictions. The core of manual therapy lies in the clinician’s skilled application of force and direction to achieve a specific therapeutic goal.
The Classification: Does PROM Fall Under Manual Therapy?
Passive Range of Motion is classified as a form of manual therapy when performed by a licensed clinician. The American Physical Therapy Association (APTA) defines manual therapy as including “skilled passive movements of joints and soft tissue,” which encompasses PROM. The distinction that elevates PROM into this category is the requirement for skilled application by the therapist, rather than the simple rote movement of a limb.
A therapist administering PROM constantly assesses the movement’s speed, direction, and the quality of resistance felt at the end of the range, known as the end-feel. This skilled assessment differentiates the therapeutic intervention from a simple movement. The clinician purposely uses their hands to apply determined forces to improve mobility, aligning with the definition of manual therapy as a hands-on treatment utilizing skilled movements.
Clinical Context: When Therapists Choose PROM
Therapists choose PROM over other range of motion techniques, such as Active Range of Motion (AROM) or Active-Assistive Range of Motion (AAROM), when the patient’s own muscle contraction is not possible or is actively discouraged. PROM is necessary for patients who are paralyzed, unconscious, or otherwise unable to generate the necessary muscle force to move a limb.
The technique is also indicated in acute phases following certain surgical procedures, such as a joint replacement, or during a period of severe inflammation or acute pain. In these situations, muscle contraction might disrupt healing tissue or cause a harmful increase in pain levels. For bed-bound patients facing long-term immobility, like those with severe stroke or advanced neurological conditions, PROM is a regular, preventative measure. It maintains the biological integrity of the joint until the patient is ready to progress to techniques that require active muscular participation.