title: Subacromial pressures vary with simulated sleep positions.
abstract: OBJECTIVE
  Subacromial impingement is one of the underlying factors of rotator cuff pathologies and is linked to increased subacromial pressures. Because humans spend about one-third of their life sleeping, we hypothesized that distinct shoulder positions while sleeping may considerably influence nocturnal subacromial pressures. Consequently, atrophy and rupture can affect tendon healing after rotator cuff repair, thus potentially discrediting the outcome of surgery.
  
  
  METHODS
  We determined the subacromial pressures acting on the rotator cuff in the 4 most common sleep positions and related these pressures to the mean arterial blood pressure and physical examination findings in 20 healthy volunteers.
  
  
  RESULTS
  Subacromial pressures were significantly lower in participants sleeping preferably in a supine position than in participants sleeping in side or prone positions (P < .005).
  
  
  CONCLUSIONS
  As tendon perfusion is crucial for tendon-to-bone healing during postoperative physical therapy after rotator cuff reconstruction and for prevention of additional damage to healthy or already torn cuffs, potential clinical relevance may emerge from the present study.
  
  
  CONCLUSIONS
  Distinct shoulder positions considerably influence subacromial pressures. Our findings may be considered in physiotherapeutic concepts after rotator cuff surgery.
authors.affiliation: Department of Surgery, Division of Trauma Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Clément M L
authors.initials: CM
authors.lastname: Werner
authors.forename: Christian
authors.initials: C
authors.lastname: Ossendorf
authors.forename: Dominik C
authors.initials: DC
authors.lastname: Meyer
authors.forename: Stephan
authors.initials: S
authors.lastname: Blumenthal
authors.forename: Christian
authors.initials: C
authors.lastname: Gerber
mesh_terms: D001284:Atrophy; D001794:Blood Pressure / Q000502:physiology; D006801:Humans; D011312:Pressure; D016059:Range of Motion, Articular; D017006:Rotator Cuff / Q000473:pathology / Q000601:surgery; D000070636:Rotator Cuff Injuries; D019534:Shoulder Impingement Syndrome / Q000503:physiopathology; D012785:Shoulder Joint / Q000502:physiology*; D012890:Sleep / Q000502:physiology*; D016683:Supine Position / Q000502:physiology