title: RADIOGRAPHIC STUDY ON THE ACROMION INDEX AND ITS RELATIONSHIP WITH ROTATOR CUFF TEARS.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the relationship between the lateral projection of the acromion and rotator cuff tears (RCTs) in the Brazilian population.
  
  
  METHODS
  The lateral projection of the acromion was measured using anteroposterior radiographs of the shoulders, carried out with the glenoid cavity in absolute profile and the humeral head in the neutral position or with internal rotation. The acromion index (AI) was defined as the ratio between the distance from the plane of the glenoid cavity to the lateral edge of the acromion and the distance from the plane of the glenoid cavity to the lateral edge of the humeral head. This index was measured in 83 patients (mean age of 54 years) with RCTs and compared with a group of 28 individuals (mean age of 48 years) without RCTs. The presence or absence of RCTs was determined by means of magnetic resonance imaging.
  
  
  RESULTS
  The mean AI was 0.7194 for the patients with RCTs and 0.6677 for the individuals without RCTs, in the Brazilian population. This difference was statistically significant, with P < 0.001.
  
  
  CONCLUSIONS
  A relationship can be established between AI and rotator cuff tears in the Brazilian population.
authors.affiliation: PhD. Assistant Professor in the Department of Orthopedics and Traumatology, School of Medical Sciences, Santa Casa de Sao Paulo; Head of the Shoulder and Elbow Group.
authors.forename: Alberto Naoki
authors.initials: AN
authors.lastname: Miyazaki
authors.affiliation: Assistant Professor in the Department of Orthopedics and Traumatology, School of Medical Sciences, Santa Casa de Sao Paulo; Attending Physician in the Shoulder and Elbow Group.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Fregoneze
authors.affiliation: Attending Physician in the Shoulder and Elbow Group.
authors.forename: Pedro Doneux
authors.initials: PD
authors.lastname: Santos
authors.affiliation: Attending Physician in the Shoulder and Elbow Group.
authors.forename: Luciana Andrade
authors.initials: LA
authors.lastname: Da Silva
authors.affiliation: Trainee Physician in the Shoulder and Elbow Group.
authors.forename: Éder
authors.initials: É
authors.lastname: Menegassi Martel
authors.affiliation: Trainee Physician in the Shoulder and Elbow Group.
authors.forename: Leandro Gervazoni
authors.initials: LG
authors.lastname: Debom
authors.affiliation: Trainee Physician in the Shoulder and Elbow Group.
authors.forename: Manoel Loyola
authors.initials: ML
authors.lastname: Andrade
authors.affiliation: PhD. Adjunct Professor and Head of Clinical Medicine of the Department of Orthopedics and Traumatology, School of Medical Sciences, Santa Casa de Sao Paulo; Academic Consultant in the Shoulder and Elbow Group.
authors.forename: Sérgio Luiz
authors.initials: SL
authors.lastname: Checchia
keywords: Acromion; Radiography; Rotator cuff