Table 3.
Differences Between Presence of Scapular Dyskinesis or Normal Scapular Arthrokinematics Clinical Assessments a
| Presence of Scapular Dyskinesis | Normal Scapular Arthrokinematics | P Value | |
|---|---|---|---|
| Scapula resting position b | |||
| Dominant upward/downward rotation (X), deg | 19.88 ± 4.11 | 16.92 ± 5.07 | .135 |
| Dominant IR/ER (Y), deg | 140.03 ± 5.02 | 136.19 ± 4.68 | .020 |
| Dominant anterior/posterior tilt (Z), deg | 4.09 ± 7.57 | –2.25 ± 10.75 | .079 |
| Dominant vs nondominant upward/downward rotation (X), deg | 0.78 ± 0.38 | 0.38 ± 3.77 | .630 |
| Dominant vs nondominant IR/ER (Y), deg | 1.95 ± 5.33 | –4.63 ± 7.33 | .011 |
| Dominant vs nondominant anterior/posterior tilt (Z), deg | 5.89 ± 10.07 | 4.07 ± 8.68 | .464 |
| ER shoulder strength, N | |||
| Dominant | 99.9 ± 27.1 | 103.6 ± 18.8 | .792 |
| Nondominant | 100.5 ± 20.1 | 96.3 ± 32.3 | .464 |
| Dominant vs nondominant | –0.6 ± 13.2 | 7.3 ± 26.8 | .533 |
| IR shoulder strength, N | |||
| Dominant | 131.3 ± 41.7 | 139.4 ± 33.6 | .911 |
| Nondominant | 126.6 ± 42.5 | 145.2 ± 41.9 | .219 |
| Dominant vs nondominant | 4.7 ± 20.0 | –5.8 ± 18.5 | .206 |
| Dominant ER:IR ratio, % | 79.8 ± 21.0 | 76.8 ± 13.3 | .999 |
| Nondominant ER:IR ratio, % | 81.3 ± 12.8 | 66.5 ± 21.2 | .018 |
| Dominant (pitching) shoulder kinematics | |||
| Maximum shoulder ER, deg | 176.38 ± 5.10 | 175.67 ± 8.04 | .837 |
| Maximum shoulder abduction, deg | 90.39 ± 7.29 | 94.35 ± 15.37 | .492 |
| Maximum horizontal shoulder abduction, deg | –48.63 ± 17.15 | –36.16 ± 11.67 | .060 |
| Maximum shoulder rotation velocity, deg/s | 4630 ± 398 | 4999 ± 461 | .016 |
| Maximum shoulder distraction force, % BW | 124.40 ± 24.9 | 137.00 ± 19.7 | .156 |
a Data are reported as mean ± SD. Statistically significant (P < .05) differences are in bold. BW, body weight; ER, external rotation; IR, internal rotation.
bX position = upward rotation is positive; Y position = internal rotation is positive; Z position = anterior tilt is negative.