title: Correlation of postoperative midfoot position with outcome following reconstruction of the stage II adult acquired flatfoot deformity.
abstract: BACKGROUND
  No studies investigating the effect of the midfoot (talonavicular joint) position on clinical outcomes following flatfoot reconstruction have been performed. The purpose of our study was to determine whether a postoperative abducted or adducted forefoot alignment, as determined from anteroposterior (AP) radiographs, was associated with a difference in outcomes using the Foot and Ankle Outcome Score (FAOS).
  
  
  METHODS
  Midfoot abduction was defined on postoperative AP radiographs, evaluated at a mean of 1.9 years in 55 patients from the authors' institution who underwent flatfoot reconstruction for a stage II adult acquired flatfoot deformity (AAFD), as a lateral incongruency angle greater than 5 degrees, a talonavicular uncoverage angle greater than 8 degrees, and a talo-first metatarsal angle greater than 8 degrees based on previously reported measurements. Patients with 2 or more measurements in the abduction category were classified as the abduction group (n = 30); those with 1 or fewer measurements in the abduction category were placed in the adduction group (n = 25). The preoperative and postoperative FAOS values with a mean follow-up of 3.1 years were compared using Wilcoxon rank-sum tests.
  
  
  RESULTS
  Patients corrected to a position of adduction showed significantly lower improvement in the FAOS daily activities (P = .012) and quality of life subscales (P = .046). The mean improvement in subscale scores for the adducted group was lower for pain (P = .052) and sports activities (P = .085) but did not reach statistical significance. No significant difference in the FAOS symptoms subscale (P = .372) between groups was found.
  
  
  CONCLUSIONS
  Correction of the talonavicular joint to a position of adduction following a stage II AAFD was associated with decreased patient outcomes in daily activities and quality of life compared with an abducted position. These results suggest that overcorrection to a position of midfoot adduction leads to a lesser amount of individual patient improvement in reconstruction of a stage II AAFD.
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Conti
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Jeremy Y
authors.initials: JY
authors.lastname: Chan
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Huong T
authors.initials: HT
authors.lastname: Do
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Scott J
authors.initials: SJ
authors.lastname: Ellis
authors.affiliation: Hospital for Special Surgery, New York, New York, USA delandj@hss.edu.
authors.forename: Jonathan T
authors.initials: JT
authors.lastname: Deland
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005413:Flatfoot / Q000523:psychology / Q000601:surgery*; D005531:Foot Deformities, Acquired / Q000523:psychology / Q000601:surgery*; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D011184:Postoperative Period; D011788:Quality of Life / Q000523:psychology; D019651:Plastic Surgery Procedures / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: adult acquired flatfoot deformity; clinical outcomes; midfoot abduction; reconstruction; talonavicular joint