Interaction of scapular dyskinesis with hand dominance on three-dimensional scapular kinematics.

INTRODUCTION: This study aimed to evaluate the effect of scapular dyskinesis and its interaction with hand dominance and humerothoracic angles on three-dimensional scapular kinematics in asymptomatic individuals in all planes of arm motion. METHODS: Forty-five asymptomatic participants, seventeen men and twenty-eight women, were separated into two groups: with (n = 22) and without scapular dyskinesis (n = 23) according to the Yes/No classification. Scapular kinematic data of dominant and non-dominant sides in both groups were measured with an electromagnetic tracking device during arm elevation and lowering phases in scapular, frontal and sagittal planes. A linear mixed model of covariance adjusted for age and BMI was used, which included hand dominance (dominant and non-dominant), group (with and without scapular dyskinesis), angles (30°, 60°, 90°, and 120°), and the interaction effect (group × hand dominance × humerothoracic angle). RESULTS: There was a significant interaction effect on scapular anterior tilt and upward rotation in the sagittal plane, and for internal rotation and anterior tilt in the frontal and scapular planes. The effects of hand dominance on three-dimensional scapular kinematics, as increased anterior tilt, internal rotation and upward rotation, were greater in individuals without scapular dyskinesis. CONCLUSION: The effects of dominant side as increased upward rotation, internal rotation, and anterior tilt at higher humerothoracic angles for all planes of arm motion, were greater in individuals without scapular dyskinesis. Our findings may assist the scapular assessment which in individuals without scapular dyskinesis, bilaterally, possible between side differences in the scapular motions may be related to a dominance effect.

Altered Scapular Time Series in Individuals With Subacromial Pain Syndrome.

Altered scapular movement in subacromial pain syndrome has been demonstrated using discrete data reduction approach. However, this approach does not consider the data collinearity and variability, and scapular translations are poorly investigated in symptomatic individuals. The purpose of this study was to investigate the scapular rotation and translation of asymptomatic individuals and those with subacromial pain syndrome during arm motions using principal component analysis. Scapulothoracic kinematics were evaluated in 47 participants with subacromial pain syndrome and 50 asymptomatic individuals. The symptomatic group had increased range of scapular anterior/posterior tilt during arm elevation (P = .01, effect size = .59) and arm lowering (P < .01, effect size = .61), and increased range of scapular forward/backward translation during arm lowering (P < .01, effect size = .60) compared with the asymptomatic group. In addition, the symptomatic group had a reduced difference in anterior tilt angular velocities between the early-arm and mid-arm lowering phases and between the mid- and late-arm lowering phases compared with the asymptomatic group (P = .03, effect size = .44). This study demonstrated that scapular anterior/posterior tilt motion and angular velocity and scapular forward/backward translation of symptomatic individuals were different from asymptomatic individuals when considering the entire arm movement.

Exercise training attenuates acute hyperalgesia in streptozotocin-induced diabetic female rats.

OBJECTIVES: We investigated the effects of chronic (eight weeks) low-to moderate-intensity swimming training on thermal pain sensitivity in streptozotocin-induced diabetic female rats. METHODS: Female Wistar rats (n = 51) were divided into the following groups: trained streptozotocin-induced diabetic rats [hyperglycemic trained (HT)], sedentary streptozotocin-induced diabetic rats [hyperglycemic sedentary (HS)], normoglycemic trained rats (NT) and normoglycemic sedentary rats (NS). Diabetes was induced by a single injection of streptozotocin (50 mg/kg, i.p.). One day after the last exercise protocol (60 min/day, five days/week for eight weeks) in the trained groups or after water stress exposure (ten min/twice a week) in the sedentary groups, the rats were subjected to a hot plate test. RESULTS: After eight weeks of swimming training, streptozotocin-induced diabetic rats presented a significantly lower body mass (trained: 219.5 ± 29 g, sedentary: 217.8 ± 23 g) compared with the normoglycemic groups (trained: 271 ± 24 g, sedentary: 275.7 ± 32 g). Interestingly, we did not find differences in blood glucose levels (mg/dl) between the trained and sedentary groups of the hyperglycemic or normoglycemic rats (HT: 360.2 ± 66.6, HS: 391.7 ± 66.7, NT: 83.8 ± 14.0, NS: 77.5 ± 10.1). In the hot plate test, the rats from the HT group presented a significantly lower latency than the other rats (HT: 11.7 ± 7.38 s, HS: 7.02 ± 7.38 s, NT: 21.21 ± 7.64 s, NS: 22.82 ± 7.82 s). CONCLUSION: Low-to-moderate swimming training for a long duration reduces thermal hyperalgesia during a hot plate test in streptozotocin-induced diabetic female rats.

Exercise training attenuates acute hyperalgesia in streptozotocin-induced diabetic female rats

OBJECTIVES: We investigated the effects of chronic (eight weeks) low-to moderate-intensity swimming training on thermal pain sensitivity in streptozotocin-induced diabetic female rats. METHODS: Female Wistar rats (n = 51) were divided into the following groups: trained streptozotocin-induced diabetic rats [hyperglycemic trained (HT)], sedentary streptozotocin-induced diabetic rats [hyperglycemic sedentary (HS)], normoglycemic trained rats (NT) and normoglycemic sedentary rats (NS). Diabetes was induced by a single injection of streptozotocin (50 mg/kg, i.p.). One day after the last exercise protocol (60 min/day, five days/week for eight weeks) in the trained groups or after water stress exposure (ten min/twice a week) in the sedentary groups, the rats were subjected to a hot plate test. RESULTS: After eight weeks of swimming training, streptozotocin-induced diabetic rats presented a significantly lower body mass (trained: 219.5±29 g, sedentary: 217.8±23 g) compared with the normoglycemic groups (trained: 271±24 g, sedentary: 275.7±32 g). Interestingly, we did not find differences in blood glucose levels (mg/dl) between the trained and sedentary groups of the hyperglycemic or normoglycemic rats (HT: 360.2±6.6, HS: 391.7±6.7, NT: 83.8±14.0, NS: 77.5±10.1). In the hot plate test, the rats from the HT group presented a significantly lower latency than the other rats (HT: 11.7±7.38 s, HS: 7.02±7.38 s, NT: 21.21±7.64 s, NS: 22.82±7.82 s). CONCLUSION: Low-to-moderate swimming training for a long duration reduces thermal hyperalgesia during a hot plate test in streptozotocin-induced diabetic female rats.