When is it advisable to start passive range of motion (PROM) and why?

When is it advisable to start passive range of motion (PROM) and why?

• A. During weeks 1 to protect tissue from movement.
• B. During weeks 2-4 to direct the collagen to lay down in certain direction which is based on load application.
• C. During weeks 5-10 to accelerate remodeling.
• D. Only after week 10.

Answer: (B)

The main idea is using a controlled, gentle amount of movement early in healing to guide how new tissue forms. After an injury or repair, the body lays down collagen in a relatively disorganized fashion. Providing gentle passive movement during the early proliferative window gives a mechanical cue that directs collagen fibers to align along the direction of the load, which helps create stronger, more functional tissue and reduces the risk of stiff scar adhesions. Starting PROM around the second to fourth week hits that favorable window. In the first week the tissue is very fragile and clot formation is still stabilizing, so movement can risk disruption. By weeks 2–4, collagen synthesis is active and the tissue responds to mechanical stimulation: the gentle stretches from PROM encourage fibers to align in the direction of movement, which improves tensile strength and long-term mobility. Beginning PROM later, in and after weeks 5–10, moves into a remodeling phase where collagen becomes more organized, but the opportunity to influence initial fiber orientation is less impactful, and delaying movement longer increases the risk of joint stiffness. Waiting until after week 10 reduces mobility gains and can lead to more adhesions. So, starting PROM in weeks 2–4 is best because it provides the right balance of protecting the healing tissue while directing collagen alignment through mechanical load.

The main idea is using a controlled, gentle amount of movement early in healing to guide how new tissue forms. After an injury or repair, the body lays down collagen in a relatively disorganized fashion. Providing gentle passive movement during the early proliferative window gives a mechanical cue that directs collagen fibers to align along the direction of the load, which helps create stronger, more functional tissue and reduces the risk of stiff scar adhesions.

Starting PROM around the second to fourth week hits that favorable window. In the first week the tissue is very fragile and clot formation is still stabilizing, so movement can risk disruption. By weeks 2–4, collagen synthesis is active and the tissue responds to mechanical stimulation: the gentle stretches from PROM encourage fibers to align in the direction of movement, which improves tensile strength and long-term mobility. Beginning PROM later, in and after weeks 5–10, moves into a remodeling phase where collagen becomes more organized, but the opportunity to influence initial fiber orientation is less impactful, and delaying movement longer increases the risk of joint stiffness. Waiting until after week 10 reduces mobility gains and can lead to more adhesions.

So, starting PROM in weeks 2–4 is best because it provides the right balance of protecting the healing tissue while directing collagen alignment through mechanical load.