Original articleThree-dimensional rotation of the scapula during functional movements: An in vivo study in healthy volunteers
Section snippets
Subjects
The inclusion criteria were that the subjects should be aged between 18 and 60 years and have normal skin integrity around the shoulder. Subjects were excluded if they were pregnant, had osteoporosis, or had current shoulder pathology. Eight healthy subjects were recruited. All chose their nondominant left shoulder to be tested. Data from 1 subject were rejected because of pin loosening (as described in the “Results” section). The mean age of the remaining subjects was 30 ± 5 years, and their
Results
The data for 1 subject were rejected. When removing the pins, the surgeon noted that the pins were loose. Data and video footage of the experiment were reviewed but could not identify a point in time when the pins failed. There appeared to be differences in the resulting movement patterns from those observed in other subjects. Although these differences could be a result of individual variation, we decided to reject the data because we could not be sure that the loosened pins moved directly
Discussion
This study described scapular motion for 4 different arm movements. It is unique in that a direct technique was used (ie, bone pins) during functional arm movements. Furthermore, the reliability of this method was assessed. During abduction, the scapula tipped posteriorly, rotated upward, and rotated externally. During reaching, the scapula rotated upward and rotated internally with a variable but small amount of scapular tipping. HBB was a small and variable movement usually consisting of
References (20)
- et al.
Comparison of scapular kinematics between elevation and lowering of the arm in the scapular plane
Clin Biomech (Bristol, Avon)
(2002) - et al.
Velocity effects on the scapulo-humeral rhythm
Clin Biomech (Bristol, Avon)
(1998) - et al.
Scapular instabilityThe scapulothoracic joint
Phys Med Rehabil Clin N Am
(2000) - et al.
Laxity of the normal glenohumeral joint: a quantitative in vivo assessment
J Shoulder Elbow Surg
(1992) - et al.
Scapular behavior in shoulder impingement syndrome
Arch Phys Med Rehabil
(2002) - et al.
Biomechanical model of the human shoulder joint—IIThe shoulder rhythm
J Biomech
(1991) - et al.
Scapular kinematics: effects of altering the Euler angle sequence of rotations
J Biomech
(2000) - et al.
Direct 3-dimensional measurement of scapular kinematics during dynamic movements in vivo
J Shoulder Elbow Surg
(2001) Dynamic stability of the scapula
Man Ther
(1997)- et al.
The effect of shoulder movements on thoracic spine 3D motion
Clin Biomech (Bristol, Avon)
(2002)
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Supported by the Natural Sciences and Engineering Research Council of Canada.