title: An oblique muscle hematoma as a rare cause of severe abdominal pain: a case report.
abstract: BACKGROUND
  Abdominal wall hematomas are an uncommon cause of acute abdominal pain and are often misdiagnosed. They are more common in elderly individuals, particularly in those under anticoagulant therapy. Most abdominal wall hematomas occur in the rectus sheath, and hematomas within the oblique muscle are very rare and are poorly described in the literature. Here we report the case of an oblique muscle hematoma in a middle-aged patient who was not under anticoagulant therapy.
  
  
  METHODS
  A 42-year-old Japanese man presented with a painful, enlarging, lateral abdominal wall mass, which appeared after playing baseball. Abdominal computed tomography and ultrasonography showed a large soft tissue mass located in the patient's left internal oblique muscle. A diagnosis of a lateral oblique muscle hematoma was made and the patient was treated conservatively.
  
  
  CONCLUSIONS
  Physicians should consider an oblique muscle hematoma during the initial differential diagnosis of pain in the lateral abdominal wall even in the absence of anticoagulant therapy or trauma.
authors: Department of General Medicine, Iida Municipal Hospital, 438 Yawata-machi, Iida, Nagano-ken, Japan. masanori19810813@yahoo.co.jp
authors: Masanori
authors: M
authors: Shimodaira
authors: Tomohiro
authors: T
authors: Kitano
authors: Minoru
authors: M
authors: Kibata
authors: Kumiko
authors: K
authors: Shirahata
mesh_terms: D015746:Abdominal Pain / Q000000981:diagnostic imaging / Q000209:etiology*; D000328:Adult; D006406:Hematoma / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography