title: Gait efficiency using the C-Leg.
abstract: Microprocessor-controlled prosthetic knees are claimed to improve gait efficiency in transfemoral (TF) amputees. This hypothesis was tested in a prospective randomized crossover trial that compared the Mauch SNS knee and the C-Leg microprocessor-controlled knee in eight TF amputees. The subjects were given a 3-month acclimation period in each knee. Then, their net oxygen cost (mL/kg/m) was measured while they walked overground at four speeds in random order: 0.8 m/s, 1.0 m/s, 1.3 m/s, and self-selected walking speed (SSWS). The C-Leg caused small reductions in net oxygen cost that were not statistically significant compared with the Mauch SNS at any of the walking speeds (p > 0.190). Subjects chose higher SSWSs with the C-Leg compared with the Mauch SNS (mean +/- standard deviation = 1.31 +/- 0.12 m/s vs 1.21 +/- 0.10 m/s, respectively, p = 0.046) but did not incur higher oxygen costs (p = 0.270), which suggests greater efficiency only at their SSWS.
authors.affiliation: Motion Analysis Laboratory, Center of Excellence for Limb Loss Prevention and Prosthetic Engineering, Department of Veterans Affairs Puget Sound Health Care System, 1660 South Columbian Way, Seattle, WA 98108, USA. morendurff@hotmail.com
authors.forename: Michael S
authors.initials: MS
authors.lastname: Orendurff
authors.forename: Ava D
authors.initials: AD
authors.lastname: Segal
authors.forename: Glenn K
authors.initials: GK
authors.lastname: Klute
authors.forename: Martin L
authors.initials: ML
authors.lastname: McDowell
authors.forename: Janice A
authors.initials: JA
authors.lastname: Pecoraro
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Czerniecki
mesh_terms: D000328:Adult; D000674:Amputees / Q000534:rehabilitation*; D000704:Analysis of Variance; D001186:Artificial Limbs; D001696:Biomechanical Phenomena; D018592:Cross-Over Studies; D004526:Efficiency / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D005269:Femur / Q000601:surgery; D005684:Gait / Q000502:physiology*; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D011336:Probability; D011446:Prospective Studies; D011474:Prosthesis Design; D012016:Reference Values; D016896:Treatment Outcome; D014728:Veterans