Enhancement of a prosthetic knee with a microprocessor-controlled gait phase switch reduces falls and improves balance confidence and gait speed in community ambulators with unilateral transfemoral amputation.

Only 13 participants completed, and the falls analysis used 12 after excluding one extreme outlier, so the study did not reach its planned minimum sample of 15. The participants were young and high functioning, with a mean age of 33.1 years and Medicare Functional Classification Level 3, so results may not apply to older or less able amputators. The order of knee conditions was not randomized, and neither participants nor assessors were blinded. The old knee condition was not standardized, and participants kept their existing prosthetic feet. Some outcome measures were developed for this study and have not yet been validated. The accommodation period was 8 weeks and training was only 2 hours, and there is no consensus on optimal accommodation time. Referral through prosthetic clinics could introduce selection bias. People who use walking aids, have poor socket fit, or have additional major amputations were excluded.

The authors declared no potential conflicts of interest, but the research grant came from Ottobock to FACTI, which employs two named authors; one author is a full-time Ottobock employee; Ottobock provided the intervention knees; and an Ottobock do Brasil prosthetist fitted them.

Do not conclude that the 3E80 knee prevents falls in all people with transfemoral amputation. The 77% fall reduction was reported in 12 participants after one extreme outlier was excluded, the study was not randomized or blinded, and the TUG, FSST, and FES-I fall risk tests were not significant.