title: Negative magnetic resonance imaging in femoral neck stress fracture with joint effusion: a case report.
abstract: Femoral neck stress fracture (FNSF) is well documented in the orthopedic literature and is generally associated with strenuous activities such as long-distance running and military training. The diagnostic yield of magnetic resonance imaging (MRI) for FNSF was reported to be 100 %, and early MRI is recommended when this fracture is suspected. We encountered a 16-year-old male long-distance runner with FNSF in whom the left femoral neck showed no signal changes on MRI although an effusion was detected in the left hip joint. One month later, roentgenograms revealed periosteal callus and oblique consolidation of the left femoral neck, confirming the diagnosis of compression FNSF. Because FNSF with a normal bone marrow signal on MRI is very rare, this patient is presented here.
authors.affiliation: Department of Orthopedic Surgery, Akita Rosai Hospital, 30 Karuizawa-Aza- Shimotai, Odate, Akita, 018-5604, Japan. sekky94545@yahoo.co.jp.
authors.forename: Nobutoshi
authors.identifier: http://orcid.org/0000-0002-9472-3490
authors.initials: N
authors.lastname: Seki
authors.affiliation: Department of Orthopedic Surgery, Akita Rosai Hospital, 30 Karuizawa-Aza- Shimotai, Odate, Akita, 018-5604, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Okuyama
authors.affiliation: Department of Orthopedic Surgery, Akita Rosai Hospital, 30 Karuizawa-Aza- Shimotai, Odate, Akita, 018-5604, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Kamo
authors.affiliation: Department of Orthopedic Surgery, Akita Rosai Hospital, 30 Karuizawa-Aza- Shimotai, Odate, Akita, 018-5604, Japan.
authors.forename: Mitsuho
authors.initials: M
authors.lastname: Chiba
authors.affiliation: Department of Orthopedic Surgery, Akita University School of Medicine, Akita, Akita, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Shimada
mesh_terms: D000293:Adolescent; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control*; D005188:False Negative Reactions; D005265:Femoral Neck Fractures / Q000150:complications / Q000000981:diagnostic imaging*; D015775:Fractures, Stress / Q000150:complications / Q000000981:diagnostic imaging*; D006801:Humans; D006833:Hydrarthrosis / Q000000981:diagnostic imaging* / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging* / Q000209:etiology
keywords: Diagnosis; Femoral neck stress fracture; Magnetic resonance imaging