Progressive abduction loading therapy targeting flexion synergy to regain reaching function in chronic stroke: Preliminary results from an RCT.

Reaching function is impaired following stroke due to abnormal coupling of shoulder abduction and elbow flexion. This phenomenon is commonly referred to as flexion synergy, loss of independent joint control, or impaired joint individuation. We have been successful in treating individuals with chronic stroke with moderate to severe motor impairments through the employment of targeted rehabilitation robotics and identified progressive abduction loading as a key element to the rehabilitation of reaching. Here we expand upon the investigation of progressive abduction loading therapy by testing two variants of the exercise in a larger sample and including a 3-month follow-up. Furthermore, we attempt to glean additional insights into the mechanisms underlying improvements by not only assessing reaching distance as a function of abduction loading but, for the first time, assessing peak reaching velocity, a combined measure of dynamic elbow and shoulder strength. Thirty-one participants with severe stroke were randomized to two intervention variants. Preliminary analysis has been performed and results are presented for blinded combined-group data. Following the intervention, there was a significant improvement in both reaching distance and peak reaching velocity. Mechanisms for improvement are briefly discussed.

Autonomic nervous system function following prenatal opiate exposure.

In utero exposure to opiates may affect autonomic functioning of the fetus and newborn. We investigated heart rate variability (HRV) as a measure of autonomic stability in prenatal opiate-exposed neonates (n = 14) and in control term infants (n = 10). Electrocardiographic data during both non-nutritive and nutritive sucking were evaluated for RR intervals, heart rate (HR), standard deviation of the consecutive RR intervals (SDRR), standard deviation of the differences of consecutive RR intervals (SDDRR), and the power spectral densities in low and high frequency bands. In controls, mean HR increased significantly, 143-161 per min (p = 0.002), with a trend toward a decrease in RR intervals from non-nutritive to nutritive sucking; these measures did not change significantly among exposed infants. Compared to controls, exposed infants demonstrated significantly greater HRV or greater mean SDRR and SDDRR during non-nutritive period (p < 0.01), greater mean SDDRR during nutritive sucking (p = 0.02), and higher powers in the low and high frequency bands during nutritive feedings. Our findings suggest that prenatal opiate exposure may be associated with changes in autonomic nervous system (ANS) functioning involving both sympathetic and parasympathetic branches. Future studies are needed to examine the effects of prenatal opiate exposure on ANS function.