title: Serial assessment of weight-bearing lower extremity alignment radiographs after open-wedge high tibial osteotomy.
abstract: OBJECTIVE
  The purpose of this study was to perform a serial assessment of the radiologic parameters of the mechanical axis (MA) and the weight-bearing line (WBL) using a weight-bearing anteroposterior (AP) long-standing view of the lower extremity to determine whether the postoperative MA and WBL change with time.
  
  
  METHODS
  A total of 90 consecutive lower limbs were examined retrospectively from a weight-bearing AP long-standing view of the lower extremity obtained from 120 patients who underwent open-wedge high tibial osteotomy (OWHTO). A total of 30 patients were excluded because of (1) complications (7 patients) such as bone graft collapse or broken screws, malunion, or nonunion arising after surgery and (2) no acquisition of a regular series of weight-bearing AP long-standing views of the lower extremity (23 patients). The AP long-standing view of the lower extremity was taken, and weight-bearing AP long-standing views of the lower extremity at 1 month, 6 months, 1 year, and 2 years postoperatively were used for assessment of serial change. The Picture Archiving Communication System (Marotech, Inc, St-Augustin-de-Desmaures, Quebec, Canada) was used for radiologic measurements of the WBL ratio and MA. Serial changes were compared between 1 month, 6 months, 1 year, and 2 years postoperatively.
  
  
  RESULTS
  The WBL ratio progressively shifted medially, with significant changes at all time points until 1 year postoperatively (1 month to 6 months, P = .04; 6 months to 1 year, P = .04; 1 year to 2 years, P = .22). Even though the MA angle showed a similar decreasing trend, it showed no statistical difference (P > .05).
  
  
  CONCLUSIONS
  This study showed that after OWHTO, the WBL shifts progressively medially until 1 year postoperatively.
  
  
  METHODS
  Level IV, diagnostic study.
authors.affiliation: Department of Orthopaedic Surgery, Seoul National University College of Medicine, Bundang Hospital, Gyeonggi-do, South Korea.
authors.forename: Yong Seuk
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Department of Orthopaedic Surgery, Gachon University, Gil Hospital, Incheon, South Korea.
authors.forename: Beom Koo
authors.initials: BK
authors.lastname: Lee
authors.affiliation: Department of Orthopaedic Surgery, Ilsan Paik Hospital, Inje University, Ilsan, South Korea.
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Kwon
authors.affiliation: Department of Orthopaedic Surgery, Ilsan Paik Hospital, Inje University, Ilsan, South Korea.
authors.forename: Jong In
authors.initials: JI
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Ilsan Paik Hospital, Inje University, Ilsan, South Korea.
authors.forename: Francis Joseph V
authors.initials: FJ
authors.lastname: Reyes
authors.affiliation: Department of Orthopaedic Surgery, Barunsesang Hospital, Seongnam, South Korea.
authors.forename: Dong Won
authors.initials: DW
authors.lastname: Suh
authors.affiliation: Department of Orthopaedic Surgery, Ilsan Paik Hospital, Inje University, Ilsan, South Korea. Electronic address: kwnhamj@hotmail.com.
authors.forename: Kyung-Wook
authors.initials: KW
authors.lastname: Nha
mesh_terms: D000328:Adult; D000368:Aged; D002170:Canada; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging; D035002:Lower Extremity / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010027:Osteotomy / Q000379:methods*; D011184:Postoperative Period; D011859:Radiography; D012189:Retrospective Studies; D013977:Tibia / Q000000981:diagnostic imaging* / Q000601:surgery*; D016474:Weight-Bearing