Article

The application of resistive forces has been used during body
weight-supported treadmill training (BWSTT) to improve walking function after
spinal cord injury (SCI).
Whether this form of training actually augments the
effects of BWSTT is not yet known. OBJECTIVE: To determine if robotic-applied
resistance augments the effects of BWSTT using a controlled experimental design
in a rodent model of SCI. METHODS: Spinally contused rats were treadmill trained
using robotic resistance against horizontal (n = 9) or vertical
(n = 8) hind limb
movements. Hind limb stepping was tested before and after 6 weeks of training.
Two control groups, one receiving standard training (ie, without resistance; n =
9) and one untrained (n = 8), were also tested. At the terminal experiment, the
spinal cords were prepared for immunohistochemical analysis of synaptophysin.
RESULTS: Six weeks of training with horizontal resistance increased step length,
whereas training with vertical resistance enhanced step height and movement
velocity. None of these changes occurred in the group that received standard (ie,
no resistance) training or in the untrained group. Only standard training
increased the number of step cycles and shortened cycle period toward normal
values. Synaptophysin expression in the ventral horn was highest in rats trained
with horizontal resistance and in untrained rats and was positively correlated
with step length. CONCLUSIONS: Adding robotic-applied resistance to BWSTT
produced gains in locomotor function over BWSTT alone. The impact of resistive
forces on spinal connections may depend on the nature of the resistive forces and
the synaptic milieu that is present after SCI.

Langue : ANGLAIS