title: Outcome of modified Kidner procedure with subtalar arthroereisis for painful accessory navicular associated with planovalgus deformity.
abstract: BACKGROUND
  Type II accessory naviculars are frequently associated with planovalgus deformity. Operative treatment for patients recalcitrant to nonoperative treatment involves resection, with or without takedown, and reattachment of the tibialis posterior tendon as described by Kidner. This does not address the planovalgus deformity. The authors hypothesized that adding a subtalar arthroereisis to the Kidner procedure would lead to improvement of pain and function and correction of the deformity.
  
  
  METHODS
  Institutional Review Board-approved, prospectively collected data were reviewed for 20 patients (23 feet), who underwent a combined modified Kidner and subtalar arthroereisis for painful type II accessory navicular with planovalgus deformity recalcitrant to nonoperative treatment. The average age at the time of surgery was 18 years. Patients were evaluated preoperatively and at final follow-up clinically, radiographically, and via the visual analog pain scale (VAPS), the American Orthopaedic Foot and Ankle Society (AOFAS) ankle hindfoot score, and a satisfaction rating. Mean follow-up was 53.9 months.
  
  
  RESULTS
  The mean AOFAS scores improved from 53 preoperatively to 95 at final follow-up and the mean VAPS score decreased from 7.4 preoperatively to 1.7 at final follow-up. Radiographically, the average Meary's angle improved from 18.5° apex plantar preoperatively to 3° apex plantar on weight-bearing lateral radiographs, and the average talar head uncoverage percentage on weight-bearing anteroposterior radiographs improved from 24% preoperatively to 3%. Nineteen of 20 patients reported good or excellent results. Three patients required implant removal because of pain; no recurrence of planovalgus deformity occurred after implant removal. No patients developed subtalar arthritis.
  
  
  CONCLUSIONS
  The modified Kidner procedure combined with a subtalar arthroereisis resulted in significant pain and functional improvement. The deformity correction obtained at surgery was maintained even if the arthroereisis plug was removed. The extra-articular plug did not lead to subtalar arthritis.
authors.affiliation: Department of Orthopaedic Surgery, OrthoCarolina, Charlotte, NC, USA.
authors.forename: David N
authors.initials: DN
authors.lastname: Garras
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Hansen
authors.forename: Adam G
authors.initials: AG
authors.lastname: Miller
authors.forename: Steven Mark
authors.initials: SM
authors.lastname: Raikin
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D002648:Child; D005260:Female; D005530:Foot Deformities / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures / Q000379:methods*; D017060:Patient Satisfaction; D019736:Prostheses and Implants; D011859:Radiography; D012189:Retrospective Studies; D013380:Subtalar Joint; D013639:Tarsal Bones / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery*; D055815:Young Adult