title: Blood flow changes of the anterior humeral circumflex artery decrease with the scapula in internal rotation.
abstract: OBJECTIVE
  Poor posture is strongly related to scapular kinematics and shoulder diseases. The purpose of this study was to clarify the blood flow changes of the anterior and posterior humeral circumflex arteries in reference to the scapular position and to clarify anatomical features related to the changes in blood flow.
  
  
  METHODS
  Cadaveric shoulders were dissected to elucidate the anatomical difference between the two arteries. The blood flow of these arteries in healthy volunteers (22-48 years, 113 shoulders) was evaluated by MRI with changing the position of the scapula (internal and external rotation).
  
  
  RESULTS
  The anterior humeral circumflex artery was attached to the subscapularis tendon and located beneath the subdeltoid bursa. The posterior humeral circumflex artery was located between the deltoid muscle and the bursa, which allowed free movement during scapular motion. There were no direct extraosseous anastomoses between the two arteries. Compared with the posterior humeral circumflex artery, the anterior humeral circumflex artery decreased blood flow with the scapula in internal rotation.
  
  
  CONCLUSIONS
  No direct extraosseous anastomoses between the two arteries were observed. Internal rotation of the scapula decreased blood flow of the anterior humeral circumflex artery, which might be related to various pathologies of the shoulder.
  
  
  METHODS
  Diagnostic studies, Level III.
authors.affiliation: Department of Orthopaedic Surgery, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan. hagi@med.tohoku.ac.jp.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Hagiwara
authors.affiliation: Department of Orthopaedic Surgery, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kanazawa
authors.affiliation: Department of Orthopaedic Surgery, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Ando
authors.affiliation: Unit of Clinical Anatomy, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
authors.forename: Akimoto
authors.initials: A
authors.lastname: Nimura
authors.affiliation: Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Radiology, Takeda General Hospital, 3-27 Yamaga-machi, Aizuwakamatsu, 965-8585, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Majima
authors.affiliation: Unit of Clinical Anatomy, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Akita
authors.affiliation: Department of Orthopaedic Surgery, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Itoi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000473:pathology / Q000503:physiopathology*; D002102:Cadaver; D005260:Female; D006801:Humans; D006811:Humerus / Q000098:blood supply*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011187:Posture; D012039:Regional Blood Flow / Q000502:physiology*; D012399:Rotation; D012540:Scapula / Q000098:blood supply*; D012785:Shoulder Joint / Q000098:blood supply / Q000503:physiopathology; D055815:Young Adult