Ll. Tis et T. Maxwell, THE EFFECT OF POSITIONING ON SHOULDER ISOKINETIC MEASURES IN FEMALES, Medicine and science in sports and exercise, 28(9), 1996, pp. 1188-1192
Weakness of the shoulder rotator musculature is a frequently encounter
ed clinical concern in shoulder injuries. However, glenohumeral intern
al and external rotation in the frontal plane (FP) in an abducted posi
tion often causes impingement of the supraspinatus tendon, whereas sim
ilar activity in the scapular plane (SP) does not cause impingement. T
herefore, the purpose of this study was to determine if assessment in
two planes affected bilateral internal and external peak torque (PT),
total work (TW), and average power (AP). Twenty recreationally active
females (age = 24.9 yr; ht = 163.3 cm; wt = 60.7 kg) were randomly ass
essed in FP and SP for dominant and nondominant side shoulder internal
rotation (IR) and external rotation (ER) isokinetic strength (Cybex 6
000, Lumex Inc., Ronkonkoma, NY). Subjects were assessed at 1.047 and
2.094 rad . s(-1) in the supine position with the shoulder abducted to
90 degrees. Four-way MANOVA revealed significant differences for PT,
TW, and AP in all measured conditions (P < 0.05). These findings indic
ate that muscular strength is affected by positioning in different pla
nes. Due to differences in PT, TW, and AP, it is advisable to maintain
consistent positioning during assessment to assure consistency in the
reporting of muscular performance variables.