title: Neuromechanical gait adaptations in women with joint hypermobility--an exploratory study.
abstract: BACKGROUND
  Joint hypermobility is known to be associated with joint and muscle pain, joint instability and osteoarthritis. Previous work suggested that those individuals present an altered neuromuscular behavior during activities such as level walking. Therefore, the aim of this study was to explore the differences in ground reaction forces, temporal parameters and muscle activation patterns during gait between normomobile and hypermobile women, including symptomatic and asymptomatic hypermobile individuals.
  
  
  METHODS
  A total of 195 women were included in this cross-sectional study, including 67 normomobile (mean 24.8 [SD 5.4] years) and 128 hypermobile (mean 25.8 [SD 5.4] years), of which 56 were further classified as symptomatic and 47 as asymptomatic. The remaining 25 subjects could not be further classified. Ground reaction forces and muscle activation from six leg muscles were measured while the subjects walked at a self-selected speed on an instrumented walkway. Temporal parameters were derived from ground reaction forces and a foot accelerometer. The normomobile and hypermobile groups were compared using independent samples t-tests, whereas the normomobile, symptomatic and asymptomatic hypermobile groups were compared using one-way ANOVAs with Tukey post-hoc tests (significance level=0.05).
  
  
  RESULTS
  Swing phase duration was higher among hypermobile (P=0.005) and symptomatic hypermobile (P=0.018) compared to normomobile women. The vastus medialis (P=0.049) and lateralis (P=0.030) and medial gastrocnemius (P=0.011) muscles showed higher mean activation levels during stance in the hypermobile compared to the normomobile group.
  
  
  CONCLUSIONS
  Hypermobile women might alter their gait pattern in order to stabilize their knee joint.
authors.affiliation: Bern University of Applied Sciences, Health Division, Discipline of Physiotherapy, Bern, Switzerland. Electronic address: stefanschmid79@gmail.com.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schmid
authors.forename: Gere
authors.initials: G
authors.lastname: Luder
authors.forename: Christine
authors.initials: C
authors.lastname: Mueller Mebes
authors.forename: Matthias
authors.initials: M
authors.lastname: Stettler
authors.forename: Ursula
authors.initials: U
authors.lastname: Stutz
authors.forename: Hans-Rudolf
authors.initials: HR
authors.lastname: Ziswiler
authors.forename: Lorenz
authors.initials: L
authors.lastname: Radlinger
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D004576:Electromyography; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology*; D007719:Knee Joint / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D055815:Young Adult
keywords: Electromyography; Ground reaction forces; Level walking