title: A functional comparison of conventional knee-ankle-foot orthoses and a microprocessor-controlled leg orthosis system based on biomechanical parameters.
abstract: BACKGROUND
  The microprocessor-controlled leg orthosis C-Brace enables patients with paretic or paralysed lower limb muscles to use dampened knee flexion under weight-bearing and speed-adapted control of the swing phase.
  
  
  OBJECTIVE
  The objective of the present study was to investigate the new technical functions of the C-Brace orthosis, based on biomechanical parameters.
  
  
  METHODS
  The study enrolled six patients. The C-Brace orthosis is compared with conventional leg orthoses (four stance control orthoses, two locked knee-ankle-foot orthoses) using biomechanical parameters of level walking, descending ramps and descending stairs.
  
  
  METHODS
  Ground reaction forces, joint moments and kinematic parameters were measured for level walking as well as ascending and descending ramps and stairs.
  
  
  RESULTS
  With the C-Brace, a nearly natural stance phase knee flexion was measured during level walking (mean value 11° ± 5.6°). The maximum swing phase knee flexion angle of the C-Brace approached the normal value of 65° more closely than the stance control orthoses (66° ± 8.5° vs 74° ± 6.4°). No significant differences in the joint moments were found between the C-Brace and stance control orthosis conditions. In contrast to the conventional orthoses, all patients were able to ambulate ramps and stairs using a step-over-step technique with C-Brace (flexion angle 64.6° ± 8.2° and 70.5° ± 12.4°).
  
  
  CONCLUSIONS
  The results show that the functions of the C-Brace for situation-dependent knee flexion under weight bearing have been used by patients with a high level of confidence.
  
  
  CONCLUSIONS
  The functional benefits of the C-Brace in comparison with the conventional orthotic mechanisms could be demonstrated most clearly for descending ramps and stairs. The C-Brace orthosis is able to combine improved orthotic function with sustained orthotic safety.
authors.affiliation: Otto Bock Healthcare, Department of Research/Biomechanics, Göttingen, Germany Thomas.Schmalz@ottobock.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmalz
authors.affiliation: Otto Bock Healthcare, Department of Research/Biomechanics, Göttingen, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Pröbsting
authors.affiliation: Otto Bock Healthcare, Department of Research and Development/Mechanics, Vienna, Austria.
authors.forename: Roland
authors.initials: R
authors.lastname: Auberger
authors.affiliation: Otto Bock Healthcare, Department of Research and Development/Orthotics, Duderstadt, Germany.
authors.forename: Gordon
authors.initials: G
authors.lastname: Siewert
mesh_terms: D000328:Adult; D000368:Aged; D001915:Braces; D004867:Equipment Design; D005260:Female; D061826:Foot Orthoses; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008838:Microcomputers; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology; D016138:Walking / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology
keywords: Biomechanics of prosthetic/orthotic devices; lower limb orthotics; rehabilitation of orthoses users; testing of prosthetic and orthotic components