title: Attachments of muscles as landmarks for implantation of shoulder hemiarthoplasty in fractures.
abstract: BACKGROUND
  The attachments of muscles and the position of the humeral head are important for a good functional outcome of shoulder hemiarthroplasties after displaced fractures of the proximal humerus. Deviations in the attachments and changes in their spatial position with respect to the humeral head during surgical reconstruction change the biomechanics and reduce the range of motion of the should joint postoperatively.
  
  
  RESULTS
  We used 198 humerus preparations and using 3-dimensional analysis measured the angular relationships between the humeral head axis and medial margin of the greater tuberosity (11.9 degrees +/- 9.1 degrees ), lateral margin of the lesser tuberosity (48.0 degrees +/- 7.8 degrees ), and the crest of the greater tuberosity (27.1 degrees +/- 9.6 degrees ).
  
  
  CONCLUSIONS
  This study provides average values of the positions of the greater and lesser tuberosities with respect to the humeral head axis. We show that the greater and lesser tuberosities are more reliable than the transepicondylar line for reconstruction of humeral head retroversion.
  
  
  METHODS
  Basic Science.
authors.affiliation: 1(St) Orthopaedic Clinic, 1(St) Faculty of Medicine, Charles University in Prague, Czech Republic. rastislav.hromadka@lf1.cuni.cz
authors.forename: Rastislav
authors.initials: R
authors.lastname: Hromádka
authors.forename: Ales Antonín
authors.initials: AA
authors.lastname: Kubena
authors.forename: David
authors.initials: D
authors.lastname: Pokorný
authors.forename: Stanislav
authors.initials: S
authors.lastname: Popelka
authors.forename: David
authors.initials: D
authors.lastname: Jahoda
authors.forename: Antonín
authors.initials: A
authors.lastname: Sosna
mesh_terms: D000704:Analysis of Variance; D019643:Arthroplasty, Replacement / Q000379:methods*; D001696:Biomechanical Phenomena; D006801:Humans; D006811:Humerus / Q000033:anatomy & histology* / Q000601:surgery; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008953:Models, Anatomic; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000601:surgery; D011336:Probability; D011474:Prosthesis Design; D017755:Prosthesis Fitting; D017006:Rotator Cuff / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D012784:Shoulder Fractures / Q000000981:diagnostic imaging / Q000601:surgery; D014057:Tomography, X-Ray Computed