title: Point-Connecting Measurements of the Hallux Valgus Deformity: A New Measurement and Its Clinical Application.
abstract: OBJECTIVE
  The aim of this study was to investigate new point-connecting measurements for the hallux valgus angle (HVA) and the first intermetatarsal angle (IMA), which can reflect the degree of subluxation of the first metatarsophalangeal joint (MTPJ). Also, this study attempted to compare the validity of midline measurements and the new point-connecting measurements for the determination of HVA and IMA values.
  
  
  METHODS
  Sixty feet of hallux valgus patients who underwent surgery between 2007 and 2011 were classified in terms of the severity of HVA, congruency of the first MTPJ, and type of chevron metatarsal osteotomy. On weight-bearing dorsal-plantar radiographs, HVA and IMA values were measured and compared preoperatively and postoperatively using both the conventional and new methods.
  
  
  RESULTS
  Compared with midline measurements, point-connecting measurements showed higher inter- and intra-observer reliability for preoperative HVA/IMA and similar or higher inter- and intra-observer reliability for postoperative HVA/IMA. Patients who underwent distal chevron metatarsal osteotomy (DCMO) had higher intraclass correlation coefficient for inter- and intra-observer reliability for pre- and post-operative HVA and IMA measured by the point-connecting method compared with the midline method. All differences in the preoperative HVAs and IMAs determined by both the midline method and point-connecting methods were significant between the deviated group and subluxated groups (p=0.001).
  
  
  CONCLUSIONS
  The point-connecting method for measuring HVA and IMA in the subluxated first MTPJ may better reflect the severity of a HV deformity with higher reliability than the midline method, and is more useful in patients with DCMO than in patients with proximal chevron metatarsal osteotomy.
authors.affiliation: Department of Orthopaedic Surgery, Dong-A University Medical Center, College of Medicine, Dong-A University, Busan, Korea.
authors.forename: Jeong-Ho
authors.initials: JH
authors.lastname: Seo
authors.affiliation: Department of Orthopaedic Surgery, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea. ilmon@hanmail.net.
authors.forename: Ji-Yong
authors.initials: JY
authors.lastname: Ahn
authors.affiliation: Department of Orthopaedic & Traumatology, Foot and Ankle, Musculoskeletal Clinic, Fatmawati General Hospital, Jakarta, Indonesia.
authors.forename: Dimas
authors.initials: D
authors.lastname: Boedijono
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005528:Foot; D006215:Hallux Valgus / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008297:Male; D008682:Metatarsal Bones / Q000000981:diagnostic imaging* / Q000601:surgery; D008683:Metatarsophalangeal Joint / Q000000981:diagnostic imaging* / Q000601:surgery; D008875:Middle Aged; D010027:Osteotomy / Q000379:methods*; D011184:Postoperative Period; D015203:Reproducibility of Results; D016474:Weight-Bearing
keywords: Hallux valgus; hallux valgus angle; intermetatarsal angle; measurement; reliability