title: Crouch gait in persons with positive sagittal spine alignment resolves with surgery.
abstract: OBJECTIVE
  Degenerative spinal conditions often result in positive sagittal alignment which may be corrected using multi-segment spinal reconstructive surgeries. The purpose of this study was to investigate gait kinematics before and after spinal reconstructive surgery in persons with positive sagittal alignment.
  
  
  METHODS
  Subjects presenting with positive sagittal alignment of greater than or equal to 7 cm who were treated with spinal reconstructive surgery were included in this study. Gait analyses were conducted pre- and 6 months post-operatively. Data were collected while subjects stood quietly for 20s and walked at their normal self-selected walking speed.
  
  
  RESULTS
  For 12 subjects, sagittal spine alignment during standing and walking was significantly decreased post-operatively (p<0.0001 for standing and p<0.0005 for walking). Prior to surgery, the subjects appeared to adopt a crouch gait with the knee flexion angle at mid terminal stance decreasing significantly after surgery (p<0.0 for the dominant lower limb and p<0.0 for the non-dominant lower limb). Additionally, dominant step length (p<0.003) and non-dominant step length (p<0.001) increased significantly after surgery.
  
  
  CONCLUSIONS
  Positive sagittal alignment resulted in crouch gait, which was resolved after multi-segment reconstructive spinal surgery that improved sagittal spinal alignment. Step and stride lengths also improved after surgical correction of the sagittal alignment.
authors.affiliation: Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, United States. Electronic address: p-gottipati@northwestern.edu.
authors.forename: Pranitha
authors.initials: P
authors.lastname: Gottipati
authors.forename: Stefania
authors.initials: S
authors.lastname: Fatone
authors.forename: Tyler
authors.initials: T
authors.lastname: Koski
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Sugrue
authors.forename: Aruna
authors.initials: A
authors.lastname: Ganju
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007738:Kyphosis / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010027:Osteotomy / Q000379:methods; D013123:Spinal Fusion / Q000379:methods*; D016896:Treatment Outcome
keywords: Crouch gait; Gait analysis; Positive sagittal alignment; Reconstruction surgery; Spinal deformity