title: Transient epiphyseal lesion of the femoral head after traumatic hip dislocation: A case report.
abstract: BACKGROUND
  We experienced a rare case in which magnetic resonance imaging (MRI) showed a transient epiphyseal lesion of the femoral head four months after traumatic hip dislocation. To our knowledge, there have been no previously published reports on the development of such transient lesions after traumatic hip dislocation involving no abnormalities just after dislocation.
  
  
  METHODS
  We report a 22-year-old man who showed a transient epiphyseal lesion of the femoral head after traumatic hip dislocation. On MRI performed two days after dislocation, no bony injuries were observed around the hip joint. Four months after dislocation, the patient suddenly experienced right hip pain without any new trauma or injury. A low-intensity band convex to the articular surface was apparent above the epiphyseal scar on T1-weighted imaging, and bone marrow edema was observed around the band lesion on short-tau inversion recovery imaging. Following a two-month period of non-surgical conservative therapy, the patient's hip pain resolved and the low-intensity band was no longer observed on follow-up MRI.
  
  
  CONCLUSIONS
  Although the detailed pathogenesis of this transient changes was unclear, we speculate that prolonged rest after traumatic hip dislocation may contribute to bone insufficiency, resulting in an insufficiency fracture of the femoral head.
  
  
  CONCLUSIONS
  This study suggests that transient epiphyseal lesions of the femoral head may occur in patients with a history of traumatic hip dislocation associated with an adapted long-term rest.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kubo
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan. Electronic address: yamataku@ortho.med.kyushu-u.ac.jp.
authors.forename: Takuaki
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Goro
authors.initials: G
authors.lastname: Motomura
authors.affiliation: Department of Orthopaedic Surgery, Yamaguchi Red Cross Hospital, 53-1 Yahatababa, Yamaguchi 753-8519, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kido
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Karasuyama
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sonoda
authors.affiliation: Department of Orthopaedic Surgery, Kyushu Rosai Hospital, 1-3-1, Kuzuharatakamatsu, Kokuraminami-ku, Kitakyushu 800-0296, Japan.
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Iwamoto
keywords: Bone marrow edema; Hip dislocation; Insufficiency fracture