title: Effects of swimming on functional recovery after incomplete spinal cord injury in rats.
abstract: One of the most promising rehabilitation strategies for spinal cord injury is weight-supported treadmill training. This strategy seeks to re-train the spinal cord below the level of injury to generate a meaningful pattern of movement. However, the number of step cycles that can be accomplished is limited by the poor weight-bearing capability of the neuromuscular system after injury. We have begun to study swimming as a rehabilitation strategy that allows for high numbers of steps and a high step-cycle frequency in a standard rat model of contusive spinal cord injury. The purpose of the present study was to evaluate the effect of swimming as a rehabilitation strategy in rats with contusion injuries at T9. We used a swimming strategy with or without cutaneous feedback based on original work in the chick by Muir and colleagues. Adult female rats (n=27) received moderately-severe contusion injuries at T9. Walking and swimming performance were evaluated using the Open-Field Locomotor Scale (BBB; Basso et al., 1995) and a novel swimming assessment, the Louisville Swimming Scale (LSS). Rats that underwent swim-training with or without cutaneous feedback showed a significant improvement in hindlimb function during swimming compared to untrained animals. Rats that underwent swim-training without cutaneous feedback showed less improvement than those trained with cutaneous feedback. Rats in the non-swimming group demonstrated little improvement over the course of the study. All three groups showed the expected improvement in over-ground walking and had similar terminal BBB scores. These findings suggest that animals re-acquire the ability to swim only if trained and that cutaneous feedback improves the re-training process. Further, these data suggest that the normal course of recovery of over-ground walking following moderately-severe contusion injuries at T9 is the result of a re-training process.
authors.affiliation: Kentucky Spinal Cord Injury Research Center, Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky 40292, USA.
authors.forename: Rebecca R
authors.initials: RR
authors.lastname: Smith
authors.forename: Alice
authors.initials: A
authors.lastname: Shum-Siu
authors.forename: Ryan
authors.initials: R
authors.lastname: Baltzley
authors.forename: Michelle
authors.initials: M
authors.lastname: Bunger
authors.forename: Angela
authors.initials: A
authors.lastname: Baldini
authors.forename: Darlene A
authors.initials: DA
authors.lastname: Burke
authors.forename: David S K
authors.initials: DS
authors.lastname: Magnuson
mesh_terms: D000818:Animals; D001676:Biofeedback, Psychology / Q000502:physiology; D001696:Biomechanical Phenomena; D005260:Female; D008124:Locomotion / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000473:pathology; D013119:Spinal Cord Injuries / Q000473:pathology / Q000503:physiopathology* / Q000534:rehabilitation; D013550:Swimming / Q000502:physiology*