title: Changes in coronal alignment of the ankle joint after high tibial osteotomy.
abstract: OBJECTIVE
  The purpose of this study was to investigate changes in coronal alignment of the ankle joint after HTO. Our hypothesis was that ankle joint orientation may become more parallel or less parallel to the ground after HTO, and this change may affect ankle symptoms.
  
  
  METHODS
  Eighty-six knees were retrospectively analysed after HTO for varus osteoarthritis. Preoperative and follow-up whole-leg radiographs were taken. The hip-knee-ankle (HKA) angle and medial proximal tibial angle (MPTA) were measured to evaluate coronal alignment of the knee. Tibial plafond inclination (TPI), talar inclination (TI), talar tilt (TT), and lateral distal tibial angle (LDTA) were measured to evaluate coronal alignment of the ankle. Patients were divided into two groups: those who exhibited a decrease in the absolute value of TPI and TI after HTO (group A) and those who exhibited an increase in the absolute value of TPI or TI after HTO (group B). Clinical outcomes of the knee and ankle were evaluated pre- and postoperatively.
  
  
  RESULTS
  Mean TPI and TI changed from 6.9° ± 3.6° and 8.0° ± 3.8° to 2.8° ± 3.1° and 3.9° ± 3.0° in group A (P < 0.001 for both) and from -1.3° ± 3.7° and 0.6° ± 4.5° to -6.0° ± 4.2° and -4.6° ± 5.9° in group B (P = 0.018 for both). VAS for ankle pain did not change significantly after HTO (n.s.) in group A, whereas those of group B increased significantly after HTO (P = 0.014).
  
  
  CONCLUSIONS
  Ankle joint orientation becomes more parallel or less parallel to the ground after HTO. Smaller preoperative HKA and LDTA result in a more valgus ankle joint orientation after HTO. Ankle symptoms were affected by coronal alignment changes of the ankle after HTO.
  
  
  METHODS
  III.
authors.affiliation: Department of Orthopaedic Surgery, Korea University College of Medicine, Ansan Hospital, 123, Jeokgeum-ro, Danwon-Gu, Ansan-si, Gyeonggi-do, 425-707, South Korea.
authors.forename: Gi Won
authors.initials: GW
authors.lastname: Choi
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, 61 Jinhwangdoro-gil, Gangdong-gu, Seoul, 134-791, South Korea.
authors.forename: Jae Hyuk
authors.initials: JH
authors.lastname: Yang
authors.affiliation: Department of Orthopaedic Surgery, Korea University College of Medicine, Ansan Hospital, 123, Jeokgeum-ro, Danwon-Gu, Ansan-si, Gyeonggi-do, 425-707, South Korea.
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, 61 Jinhwangdoro-gil, Gangdong-gu, Seoul, 134-791, South Korea.
authors.forename: Ho Hyun
authors.initials: HH
authors.lastname: Yun
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, 61 Jinhwangdoro-gil, Gangdong-gu, Seoul, 134-791, South Korea.
authors.forename: Yong In
authors.initials: YI
authors.lastname: Lee
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, 61 Jinhwangdoro-gil, Gangdong-gu, Seoul, 134-791, South Korea.
authors.forename: Jin Eon
authors.initials: JE
authors.lastname: Chae
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, 61 Jinhwangdoro-gil, Gangdong-gu, Seoul, 134-791, South Korea. momyjr@naver.com.
authors.forename: Jung Ro
authors.initials: JR
authors.lastname: Yoon
mesh_terms: D000368:Aged; D000843:Ankle Joint / Q000502:physiology*; D017760:Bone Malalignment / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D035002:Lower Extremity / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D000072458:Orientation, Spatial; D010003:Osteoarthritis; D010027:Osteotomy; D011184:Postoperative Period; D011859:Radiography; D012189:Retrospective Studies; D013977:Tibia / Q000601:surgery*
keywords: Alignment; Ankle; High tibial osteotomy; Knee