Early Intensive Exercise to Improve Walking in Children With Spastic Diplegia

Children born prematurely are at risk of brain injury that can result in cerebral palsy(CP), most often affecting the legs, called spastic diplegia. Current treatment is largely passive, including leg braces, repeated injection of a paralyzing agent (Botox) in muscles that are abnormally active, and surgery as deformities occur. Active, physical therapy for weak muscles is infrequent, occurring twice a month or less. Yet, recent work with mammals show that early brain injury can be alleviated by intensive exercise therapy, but only while the animal is very young. Building on the success with early, intensive therapy for children with perinatal (around birth) stroke, the investigators will apply intensive therapy for the legs in children with diplegia. Children (8 mo - 3 yr old) will be randomly assigned to start treatment immediately or delay treatment for 3 mo. The delay period controls for improvement without treatment. These children will also receive treatment after the delay period. The therapy will be guided by physical therapists, and similar to the project on perinatal stroke. Children who live beyond commuting distance from the centres will form a 3rd group, whose parents will be coached by therapists to train the child at home. This group will show whether parents can be as effective as a therapist. Finally, when all children turn 4 yr old, they will be compared to other 4-yr-old children with the same diagnosis, but no training, to determine if there are long term benefits. The investigators anticipate that like the children with perinatal stroke, early intensive exercise will improve mobility, facilitate earlier and better walking, and that the effects will be enduring.

• Intensive leg training with a physical therapist (Behavioral), also known as Therapist training: Intensive, self initiated activities of the lower extremities including walking over ground or on a treadmill (with or without support), kicking, jumping, standing balance, climbing stairs and slopes and other leg activities. Small weights will be added to the ankle and foot to increase the intensity of the exercise. A physical therapist will supervise sessions.

Primary outcomes

• Change in Gross Motor Functional Measure - 66 Items (GMFM-66) over 3 months [Baseline, 3 months]: This is a 66 item criterion-referenced observational measure to assess change in gross motor function of children with cerebral palsy.

Secondary outcomes

• Change in forces during treadmill walking over 3 months [Baseline, 3 months]: The child will be supported to walk on a treadmill while we record the leg motions and the forces under the feet during walking.

Sex: All, ages: 8 Months to 36 Months

Inclusion Criteria:

* children aged 8 mo - 3 yr old
* Evidence of periventricular white matter injury on diagnostic imaging
* clinical evidence of spastic diplegia

Exclusion Criteria:

* born before gestational age of 25 weeks
* birth weight <1000g (to exclude confounds related to extreme prematurity and low birth weights)
* MRI evidence of diffuse injury to the cerebral or cerebellar cortex
* uncontrolled epilepsy or infantile spasms in the past 6 months (contraindication for TMS)
* cardiovascular or musculoskeletal complications that preclude participation in intensive exercise
* Botulinum toxin (BTX-A) injections in the last 6 months
* Predicted GMFCS 4 or 5

• Jaynie Yang, PhD, Principal investigator, University of Alberta
• Monica Gorassini, PhD, Principal investigator, University of Alberta