title: The influence of arm and shoulder position on the bear-hug, belly-press, and lift-off tests: an electromyographic study.
abstract: BACKGROUND
  Clinical testing for the integrity of the subscapularis muscle includes the belly-press, lift-off, and bear-hug examinations. While these tests have been widely applied in clinical practice, there is considerable variation in arm positioning within each clinical examination.
  
  
  OBJECTIVE
  To determine the ideal arm and shoulder positions for isolating the subscapularis muscle while performing the bear-hug, belly-press, and lift-off tests.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  The activity of 7 muscles was monitored in 20 healthy participants: upper and lower divisions of the subscapularis, supraspinatus, infraspinatus, latissimus dorsi, teres major, triceps, pectoralis major. Electromyogram data were collected and compared across each clinical test at varying arm positions: bear-hug (ideal position, 10° superior, 10° inferior to the shoulder line), belly-press (ideal position, maximum shoulder external rotation, and maximal shoulder internal rotation), and lift-off (ideal position, hand position 5 in. [12.7 cm] superior and 5 in. [12.7 cm] inferior to the midlumbar spine).
  
  
  RESULTS
  Regardless of arm and shoulder position, the upper and lower subscapularis muscle activities were significantly greater than all other muscles while performing each test. No significant differences were observed between the upper and lower subscapularis divisions at any position within and across the 3 tests. There were no significant differences in subscapularis electromyogram activities across the 3 tests.
  
  
  CONCLUSIONS
  The level of subscapularis muscle activation was similar among the bear-hug, belly-press, and lift-off tests. The 3 tests activated the subscapularis significantly more than all other muscles tested but were not different from one another when compared across tests and positions. Although the bear-hug and lift-off tests have been described to activate differential portions of the subscapularis, the findings of this study do not support the preferential testing of a specific subscapular division across the 3 tests. As such, all 3 tests are effective in testing the integrity of the entire subscapularis muscle, although there does not appear to be an ideal position for selectively testing its divisions.
  
  
  CONCLUSIONS
  Clinicians may feel comfortable in using any of the 3 tests, depending on the patient, to isolate the function of the subscapularis as a single muscle. Furthermore, clinicians should not solely focus on a patient's arm position when administering an examination but also compare the affected arm to the contralateral shoulder when appropriate.
authors.affiliation: Biomechanics Research Department, Steadman-Philippon Research Institute, The Steadman Clinic, 181 West Meadow Drive, Vail, CO 81657, USA.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Pennock
authors.forename: W Wesley
authors.initials: WW
authors.lastname: Pennington
authors.forename: Michael R
authors.initials: MR
authors.lastname: Torry
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Decker
authors.forename: Suketu B
authors.initials: SB
authors.lastname: Vaishnav
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Provencher
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Millett
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Hackett
mesh_terms: D000293:Adolescent; D000328:Adult; D001132:Arm / Q000502:physiology*; D015331:Cohort Studies; D004576:Electromyography / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D010808:Physical Examination; D012399:Rotation; D017006:Rotator Cuff / Q000503:physiopathology; D012782:Shoulder / Q000502:physiology*; D013708:Tendon Injuries / Q000175:diagnosis; D055815:Young Adult