title: Ground-reactive forces after hallux valgus surgery: comparison of Scarf osteotomy and arthrodesis of the first metatarsophalangeal joint.
abstract: OBJECTIVE
  The purpose of this study was to analyse the biomechanics of walking, through the ground reaction forces (GRF) measured, after first metatarsal osteotomy or metatarsophalangeal joint (MTP) arthrodesis.
  
  
  METHODS
  A total of 19 patients underwent a Scarf osteotomy (50.3 years, standard deviation (sd) 12.3) and 18 underwent an arthrodesis (56.2 years, sd 6.5). Clinical and radiographical data as well as the American Orthopaedic Foot and Ankle Society (AOFAS) scores were determined. GRF were measured using an instrumented treadmill. A two-way model of analysis of variance (ANOVA) was used to determine the effects of surgery on biomechanical parameters of walking, particularly propulsion.
  
  
  RESULTS
  Epidemiological, radiographical and clinical data were comparable in the two groups and better restoration of propulsive function was found after osteotomy as shown by ANOVA (two way: surgery × foot) with a surgery effect on vertical forces (p < 0.01) and a foot effect on anteroposterior impulse (p = 0.01).
  
  
  CONCLUSIONS
  Patients who underwent Scarf osteotomy had a gait pattern similar to that of their non-operated foot, whereas those who underwent arthrodesis of the first (metatarsophalangeal) MTP joint did not totally recover the propulsive forces of the forefoot.
  
  
  CONCLUSIONS
  The main findings of this study were that after surgical correction for hallux valgus, patients who underwent scarf osteotomy had a gait pattern similar to that of their non-operated foot in terms of forefoot propulsive forces (Fz3, Iy2), whereas those who underwent arthrodesis of the first MTP joint had not. Cite this article: Bone Joint J 2016;98-B:641-6.
authors.affiliation: UFR SHE , Le Tampon, La Réunion Island, France.
authors.forename: R
authors.initials: R
authors.lastname: Ballas
authors.affiliation: University of Lyon, Laboratory of Exercise Physiology (LPE EA 4338), Saint Etienne, France.
authors.forename: P
authors.initials: P
authors.lastname: Edouard
authors.affiliation: Centre d'Orthopédie Traumatologie CHU de Saint-Etienne, 42055 Saint-Etienne Cedex2, France.
authors.forename: R
authors.initials: R
authors.lastname: Philippot
authors.affiliation: Centre d'Orthopédie Traumatologie CHU de Saint-Etienne, 42055 Saint-Etienne Cedex2, France.
authors.forename: F
authors.initials: F
authors.lastname: Farizon
authors.affiliation: Hôpital Privé de la Loire (HPL), 39 Boulevard de la Palle 42100 Saint Etienne, France.
authors.forename: F
authors.initials: F
authors.lastname: Delangle
authors.affiliation: Université de La Réunion, Laboratoire IRISSE (EA4075), UFR SHE, Le Tampon, La Réunion Island, France.
authors.forename: N
authors.initials: N
authors.lastname: Peyrot
mesh_terms: D001174:Arthrodesis; D001696:Biomechanical Phenomena / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D005545:Forefoot, Human / Q000503:physiopathology*; D005684:Gait / Q000502:physiology*; D006215:Hallux Valgus / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008682:Metatarsal Bones / Q000601:surgery; D008683:Metatarsophalangeal Joint / Q000601:surgery; D008875:Middle Aged; D010027:Osteotomy; D016138:Walking / Q000502:physiology
keywords: Ground reaction forces; Scarf osteotomy; first metatarsophalangeal arthrodesis; hallux valgus; treadmill ergometer