title: Risk Factors, Pathobiomechanics and Physical Examination of Rotator Cuff Tears.
abstract: BACKGROUND
  It is important to appreciate the risk factors for the development of rotator cuff tears and specific physical examination maneuvers.
  
  
  METHODS
  A selective literature search was performed.
  
  
  RESULTS
  Numerous well-designed studies have demonstrated that common risk factors include age, occupation, and anatomic considerations such as the critical shoulder angle. Recently, research has also reported a genetic component as well. The rotator cuff axially compresses the humeral head in the glenohumeral joint and provides rotational motion and abduction. Forces are grouped into coronal and axial force couples. Rotator cuff tears are thought to occur when the force couples become imbalanced.
  
  
  CONCLUSIONS
  Physical examination is essential to determining whether a patient has an anterosuperior or posterosuperior tear. Diagnostic accuracy increases when combining a series of examination maneuvers.
authors.affiliation: Steadman Philippon Research Institute 181 West Meadow Drive, Suite 1000 Vail, CO, 81657, USA.
authors.forename: Samuel G
authors.initials: SG
authors.lastname: Moulton
authors.affiliation: Steadman Philippon Research Institute 181 West Meadow Drive, Suite 1000 Vail, CO, 81657, USA.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Greenspoon
authors.affiliation: Steadman Philippon Research Institute 181 West Meadow Drive, Suite 1000 Vail, CO, 81657, USA; The Steadman Clinic, 181 West Meadow Drive Vail, CO, 81657, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Millett
authors.affiliation: Steadman Philippon Research Institute 181 West Meadow Drive, Suite 1000 Vail, CO, 81657, USA; The Steadman Clinic, 181 West Meadow Drive Vail, CO, 81657, USA.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Petri
keywords: Force couples; Natural history; Pathobiomechanics; Physical examination; Risk factors; Rotator cuff tear; Shoulder; Shoulder joint