title: Results of operative correction of grade IIB tibialis posterior tendon dysfunction.
abstract: BACKGROUND
  The prevalence of tibialis posterior tendon dysfunction (PTTD) is estimated to be as high as 3% to 4% in Western populations, and it is one of the most commonly misdiagnosed conditions of the foot and ankle.
  
  
  METHODS
  Clinical and radiological outcomes were assessed in grade IIB PTTD treated with a medializing calcaneal osteotomy, lateral column lengthening, flexor digitorum longus transfer, and tendo-Achilles lengthening. The clinical and radiological findings recorded were the SF-36 score on physical function and mental health, midfoot and hindfoot American Orthopaedic Foot and Ankle Society (AOFAS) clinical scores, the midfoot and visual analog pain scores, as well as the radiological measurements of the hindfoot calcaneal pitch, talo-first metatarsal angle, and medial cuneiform height. The time points of assessment were preoperatively, 6 months postoperatively, and 24 months postoperatively by an examiner different from the operating surgeon.
  
  
  RESULTS
  The SF-36 score on physical function (mean difference of 8.7 and 8.2, respectively), AOFAS midfoot score (mean difference of 29.6 and 15.3, respectively), AOFAS ankle-hindfoot score (mean difference of 23.2 and 14.3, respectively), midfoot visual analog pain score (mean difference of 4.0 and 1.2), and the ankle and hindfoot visual analog score (mean difference of 3.6 and 1.6) all had significant reduction from the preoperative to the 24-month postoperative time point (P < .001). Radiologically, there was also correction of the deformity associated with PTTD. The hindfoot calcaneal pitch was corrected from 8.4 degrees to 18.7 degrees. The talo-first metatarsal angle was corrected from 14.0 degrees to 1.3 degrees, and the medial cuneiform height was corrected from 10.3 mm to 20.4 mm at 24 months postoperatively.
  
  
  CONCLUSIONS
  Grade IIB PTTD treated with a medializing calcaneal osteotomy, lateral column lengthening, flexor digitorum longus transfer, and tendo-Achilles lengthening demonstrated statistical significant improvement in hindfoot and midfoot AOFAS scores, SF-36 physical function scores, as well as visual analog scores. The complications were minimal. We advocate the combination of these procedures as being successful for the treatment of grade IIB PTTD. Longer term follow-up is needed to determine if these improvements plateau, improve, or deteriorate.
  
  
  METHODS
  Level IV, retrospective case series.
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Singapore amila157@hotmail.com.
authors.forename: M G Amila N
authors.initials: MG
authors.lastname: Silva
authors.affiliation: Yong Loo Lin School of Medicine, Singapore.
authors.forename: Si Heng Sharon
authors.initials: SH
authors.lastname: Tan
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Singapore.
authors.forename: Hwei Chi
authors.initials: HC
authors.lastname: Chong
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Singapore.
authors.forename: Hsien Ching David
authors.initials: HC
authors.lastname: Su
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Singapore.
authors.forename: Inderjeet Rikhraj
authors.initials: IR
authors.lastname: Singh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010027:Osteotomy / Q000379:methods; D037081:Posterior Tibial Tendon Dysfunction / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D011859:Radiography; D012189:Retrospective Studies; D013709:Tendon Transfer / Q000379:methods; D058971:Tenotomy / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult
keywords: biomechanics; clinical outcome study; hindfoot disorders; tibialis posterior tendon dysfunction