title: Tibia segment deformation in response to simulated muscle forces: a cadaveric study with a novel optical segment tracking (OST) approach.
abstract: OBJECTIVE
  A novel optical segment tracking (OST) approach reliant upon motion capturing was previously proposed to assess human tibia segment deformation. The purposes of the present study were to validate the OST approach and assess the contribution of muscular forces to the bone deformation in a well-defined ex vivo human model.
  
  
  METHODS
  A custom-made Lower Extremity Loading Device (LELD) was developed to simulate physiological muscle contractions in six human cadaveric lower extremities. Tibia segment deformation was measured by tracking the relative movement between two marker clusters which were affixed into the proximal and distal tibia, respectively.
  
  
  RESULTS
  Compared to the physiological norms, the simulated muscle forces remained at a low level. When quadriceps muscle was loaded with forces from 198 N to 505 N, posterior bending (0.12°-0.25°) and lateral bending (0.06°-0.21°) of the tibia segment were found. Large tibia bending angles were found when simulating the co-contraction of upper leg muscles and plantar flexors, and of all leg muscles, respectively. The standard deviations of the deformation angles between the repetitions remained at a low level.
  
  
  CONCLUSIONS
  We conclude that the OST approach has the potential to be applied in vivo and quantify muscle-induced bone deformations.
authors.affiliation: Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, China.
authors.forename: P-F F
authors.initials: PF
authors.lastname: Yang
authors.forename: K
authors.initials: K
authors.lastname: Engel
authors.forename: M
authors.initials: M
authors.lastname: Sanno
authors.forename: J
authors.initials: J
authors.lastname: Dargel
authors.forename: K
authors.initials: K
authors.lastname: Wegmann
authors.forename: G-P
authors.initials: GP
authors.lastname: Brüggemann
authors.forename: J
authors.initials: J
authors.lastname: Rittweger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D005528:Foot / Q000502:physiology; D006801:Humans; D007866:Leg / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology; D008297:Male; D009038:Motion; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000502:physiology*; D013977:Tibia / Q000033:anatomy & histology* / Q000502:physiology*