title: Irreducible plantar dislocation of the interphalangeal joint of the great toe due to an accessory sesamoid bone: a case report.
abstract: BACKGROUND
  Great toe dislocation frequently occurs at the metatarsophalangeal joint. However, an irreducible dislocation of the great toe interphalangeal (IP) joint due to an accessory sesamoid bone is relatively unusual.
  
  
  METHODS
  A 23-year-old woman suffered a dislocated IP joint of the left great toe. The distal phalanx was plantar subluxated, and the articular surface was misaligned. Ultrasound, magnetic resonance imaging, and computed tomography images did not indicate any factors inhibiting reduction. In addition, the sesamoid bone at the IP joint was found to be rotated in the long-axis direction. The sesamoid bone of the IP joint was hooked from the distal direction and occupied the intercondylar area. IP joint of the left great toe was flexed and the distal phalanx was pushed toward the proximal phalanx during reduction locking with fluoroscopic guidance under local anesthesia, and the dislocation was successfully reduced.
  
  
  CONCLUSIONS
  The sesamoid bone at the IP joint is anatomically located dorsal to the flexor hallucis longus tendon and volar plate. The sesamoid bone fitted exactly in the distal intercondylar area. The sesamoid bone in our patient could be rotated by forcible plantar flexion of the IP joint displaced proximally and hooked into the intercondylar area from the proximal aspect. Then, the distal phalanx was pulled proximally through the volar plate. This is the first report on a plantar dislocation of the IP joint.
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.|Department of Orthopedic Surgery, Graduate School of Medical Science, Kanazawa University, Takaramachi 13-1, Kanazawa, Ishikawa, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Ohmori
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan. katsuo-s@mua.biglobe.ne.jp.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Katsuo
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Sunayama
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Mizuno
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Ojima
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Yamakado
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Tomonari
authors.initials: T
authors.lastname: Ando
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: Department of Orthopedic Surgery, Fukui General Hospital, 58-16-1 Egami, Fukui, Fukui, 910-8561, Japan.
authors.forename: Seigaku
authors.initials: S
authors.lastname: Hayashi
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Science, Kanazawa University, Takaramachi 13-1, Kanazawa, Ishikawa, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsuchiya
mesh_terms: D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D008349:Manipulation, Orthopedic; D012716:Sesamoid Bones / Q000002:abnormalities*; D014033:Toe Joint / Q000293:injuries*; D055815:Young Adult
keywords: Interphalangeal (IP) joint; Locking; Plantar dislocation; Sesamoid bone