title: Correction of rigid equinovarus deformity using a multiplanar external fixator.
abstract: BACKGROUND
  The rigid equinovarus foot deformity is a challenging condition treated by the orthopaedic foot and ankle surgeon. Rapid surgical correction of the deformity may lead to skin and neurologic complications. Gradual correction of the deformity with a multiplanar external fixator may decrease these complications. The purpose of this study was to present the results of a group of patients with rigid equinovarus deformities corrected using a multiplanar external fixator.
  
  
  METHODS
  We retrospectively reviewed the results of correction of a rigid equinovarus deformity using multiplanar external fixation in a small group of patients. All patients underwent open Achilles lengthening, posterior capsule release, tibialis posterior tendon lengthening, flexor digitorum longus and flexor hallux longus lengthening, followed by application of a multiplanar external fixator with gradual correction of the deformity over a period of several weeks. Preoperative and postoperative deformity and AOFAS ankle-hindfoot scores were assessed.
  
  
  RESULTS
  A total of eight rigid equinovarus deformities in six patients were treated with a multiplanar external fixator. The average patient age at the time of surgery was 37.2 (range, 17 to 59 ± 15.0) years. Causes of the deformity included trauma in three patients, traumatic brain injury in two patients, and long-standing rheumatoid arthritis in one patient. The average preoperative AOFAS ankle-hindfoot score was 28.3 (range, 12 to 38 ± 7.7). The average postoperative AOFAS ankle-hindfoot score was 68.1 (range 38 to 86 ± 15.5) at an average followup of 71.9 (30 to 120 ± 36.2) weeks. All deformities were gradually corrected to a plantigrade foot using a multiplanar external fixator over an average time of 5 (range, 4 to 6 ± 0.8) weeks. After correction of the deformity, the external fixator was left in place for a time period equal to or twice the length of time it took to achieve correction. The average duration of external fixation was 10.8 (range, 8 to 16 ± 2.8) weeks. Seven of eight deformities maintained correction at final followup. There was one case of recurrence.
  
  
  CONCLUSIONS
  Correction of a rigid equinovarus deformity using a multiplanar external fixator was a viable treatment option. It allowed for correction of the deformity in a controlled manner, helping to reduce the risk of neurovascular complications that may result from single stage surgical correction. The risk of wound complications still exists with the correction of such a complex deformity.
authors: Orthopedic Foot and Ankle Center, Westerville, OH 43082, USA.
authors: Daniel J
authors: DJ
authors: Cuttica
authors: William T
authors: WT
authors: Decarbo
authors: Terrence M
authors: TM
authors: Philbin
mesh_terms: D000293:Adolescent; D000328:Adult; D000843:Ankle Joint / Q000503:physiopathology; D004863:Equinus Deformity / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D004867:Equipment Design; D016267:External Fixators; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D055815:Young Adult