How to do range-of-motion for the knee and ankle
Passive range of motion means you move the resident's joints for them while they stay relaxed. The idea that makes it click: you are the resident's muscles, so you support the limb above and below the joint, move slowly, and stop the instant you feel resistance or hear discomfort — you never push a joint past where it wants to go.
Step-by-step
- 1
Knock, wash your hands, introduce yourself, identify the resident by name, explain the exercise, and provide for privacy.
- 2
Position the resident flat on their back (supine) with the leg to be exercised accessible.
- 3
Tell the resident to report any pain or discomfort before you begin, and ask again during the movements.Critical
- 4
Exercise only the correct joints on the correct side — the assigned knee and ankle.Critical
- 5
Support the leg above and below the knee: one hand under the knee, the other under the ankle or heel.Critical
- 6
Knee flexion: slowly bend the knee, sliding the heel toward the buttock.
- 7
Knee extension: slowly straighten the leg back flat to the bed.
- 8
Repeat the knee flexion/extension the required number of times (commonly 3-5), unless the resident reports pain.
- 9
Support the ankle with one hand and cup the heel or foot with the other.Critical
- 10
Ankle dorsiflexion: gently push the foot so the toes point up toward the head.
- 11
Ankle plantarflexion: gently point the foot and toes down away from the body; repeat both ankle motions the required number of times.
- 12
Move slowly and smoothly and stop at the point of pain or resistance — never force a joint past its free range.Critical
- 13
Return the leg to a comfortable position, ensure comfort and safety, place the call light within reach, wash your hands, and report any pain, resistance, or skin changes.
Critical steps (do not miss these)
- Support the limb both above and below the joint being exercised throughout every motion.
- Move slowly and gently and stop immediately at pain or resistance — never force the joint.
- Instruct the resident to report discomfort before AND during the exercise (NNAAP scores this verbalization).
- Perform the tested motions: knee flexion/extension and ankle dorsiflexion/plantarflexion, on the correct side.
Common mistakes
- Supporting only one side of the joint so the joint bends unsupported.
- Moving too fast or forcing past resistance instead of stopping.
- Forgetting to tell the resident to report pain or discomfort before and during.
- Skipping a repetition or doing the wrong side/joint.
Why it matters
In a relaxed limb the resident can't protect their own joints, so cradling above and below the joint keeps the movement in the joint rather than stressing the bones around it. Slow, gentle motion stopped at resistance prevents tearing tight or contracted tissue, and the report-discomfort cue turns the resident into your early-warning system — the reason those verbal and support steps are automatic-fail points on the exam.