The clinical effects of the Össur Power Knee with phase-based and default control during sitting, standing, and walking.

Seven participants is too few to show how most users would respond, and splitting them into four higher-mobility and three lower-mobility people makes each group small. All testing was in a laboratory, and the tasks were made intentionally hard and short to reveal fatigue differences; that does not match a full day of ordinary walking or transfers. Participants had only one up to 4-hour acclimation session for each Power Knee controller, so some effects may change with longer practice or take-home use. The Power Knee conditions could not be blinded against the passive prosthesis, and the informal interviews were not scripted, so participant feedback may be biased. Some participants did not complete every condition: one stopped the phase-based shuttle test because the knee overheated, one declined the phase-based treadmill test for safety, and one did not give passive-prosthesis interview feedback. The study measured biomechanics and lab performance, not long-term health, pain, falls, independence, or cost. The paper did not pre-specify a single primary outcome; it grouped many outcomes and corrected within domains.

Do not conclude that the Power Knee improves everyday walking, transfers, or health. This was a small laboratory study of seven users, it did not show faster or longer walking, and some higher-mobility users had slower transitions or fewer laps.