title: A histopathological evaluation of a concave-shaped low-intensity band on T1-weighted MR images in a subchondral insufficiency fracture of the femoral head.
abstract: A 73-year-old female suffered from right hip pain without any history of antecedent trauma. The initial radiograph showed a slight narrowing of the joint space in the right hip. The patient was treated by non-weight bearing for 5 weeks. Radiographs obtained 3 months after the onset of pain showed the progression of both the joint-space narrowing and subchondral collapse at the superior portion. T1-weighted MR (magnetic resonance) images obtained 3 months after the onset revealed an irregular-shaped low-intensity area just beneath the articular cartilage as well as a low-intensity band, which was concave to the articular surface. A total hip replacement was performed. A histopathological examination revealed fracture callus and granulation tissue in the subchondral area. This subchondral fractured area was surrounded by vascular rich granulation tissue and fibrous tissue, which corresponded to the concave-shaped low-intensity band observed on the T1-weighted image.
authors: Department of Orthopaedic Surgery, Kyushu University, 3-1-1 Maidashi, Fukuoka 812-8582, Japan.
authors: Garida
authors: G
authors: Zhao
authors: Takuaki
authors: T
authors: Yamamoto
authors: Satoshi
authors: S
authors: Ikemura
authors: Yasuharu
authors: Y
authors: Nakashima
authors: Taro
authors: T
authors: Mawatari
authors: Goro
authors: G
authors: Motomura
authors: Yukihide
authors: Y
authors: Iwamoto
mesh_terms: D000368:Aged; D005260:Female; D005265:Femoral Neck Fractures / Q000473:pathology*; D015775:Fractures, Stress / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*