Exercise as it relates to Disease/Effect of Hippotherapy on functionality in children with Cerebral Palsy

This Wikibooks critque was undertaken on the research article "Changes in Dynamic Trunk/Head Stability and Functional Reach after Hippotherapy" by Tim Shurtleff, John Standeven and Jack Engsberg. (2009)

Background to Research
Cerebral Palsy is a disease involving impaired voluntary movement or posture. This can result from Central Nervous System damage occurring perinatal or postnatal. This condition is non progressive and is discovered before the child reaches the age of 5. Ataxia, Spasticity, or involuntary movement are the symptoms presented with this disease. For children with this motor disease, functionality and movement are impaired causing everyday tasks and participation with peers to become difficult. This study explored the effect of horse riding, termed Hippotherapy has on children with Spastic Diplegia Cerebral Palsy in relation to their head and trunk stability as well as functional reach.

Where is the Research From?
This study was undertaken by Shurtleff, Standeven and Engsberg at the, Washington University School of Medicine in St. Louis as part of the Program in Occupational Therapy. It was published in Archives of Physical Medicine and Rehabilitation during 2009. Shurtleff is an instructor in Occupational Therapy and Neurosurgery. He has undertaken multiple studies on Hippotherapy and its effect on Cerebral Palsy patients. He has also undertaken research on the therapeutic effects of horse riding on other disabilities.

What Kind of Research was this?
The study design for this article was a case-control study as the design involved children who had Cerebral Palsy and a control group that did not have the disease. This article is also classified as an observational analytical design because it allows the testing of a hypothesis. The choice of type of study was efficient as it provided the researchers with a comparison of results for development of children without the disability. This ensured results were significant in decreasing the effect this disability has on the children’s lives. There were also Quasi-Experimental elements as the groups were not randomised as this was not required. The child either suffered from the disability or did not. One of the aims of this study was to develop a quantitative measure of changes to head and trunk stability after Hippotherapy intervention on children with Cerebral Palsy. Prior to this study, quantitative results had not been produced.1 This ensures a better interpretation of results produced when comparing before and after the intervention was undertaken.

What did the Research Involve?
11 children that are affected by the disability; Cerebral Palsy, aged from 5-17 years of age took part in this study. The control group, consisting of eight children were used as a comparison for children without disabilities for normative development values. This group matched the ages of the children with the disability. Occupational therapy sessions were carried out to identify specific disabilities and develop an individualised intervention for each participant. Although these assessments were done over three different locations, the same intervention tools were specified for this type of therapy which ensured normalisation. All children in this study underwent the same process to assess the effect of this therapy. The steps involved were; pre intervention test, individualised therapy routine and two post intervention tests. The pre and post intervention tests carried out the same procedure under video analysis to collect quantitative data used to determine if the therapy was successful. Pre intervention and the first post intervention were completed two weeks either side of the therapy. The second post intervention test was completed 12-14 weeks after therapy where subjects had not ridden during this period. Pre and post intervention tests were undertaken in a lab-based environment, replicating the movement of the horse using a barrel. This procedure was undertaken as motion analysis systems are not portable so would not give accurate results in a riding area. The actual Hippotherapy sessions undertaken involved; This occurs while; Subject Inclusion criteria included; Subject Exclusion criteria included;
 * 45-minute horse riding sessions, once per week for 12 continuous weeks
 * Performed in the walk and trot gait
 * The horse is directed by the handler to stop, start, change speed or gait, weave through cones, turn in circles or navigate over different terrain.
 * The child is engaged in changes in position on the saddle (eg sideways or backwards facing, kneeling and quadruped)
 * Cognitive games such as memory tasks or finding objects around the riding area
 * Catching/throwing games and placing objects on stationary surfaces
 * Functional reaching and stretching tasks through each plane of motion
 * Be able to sit on a static surface unaided, be able to communicate and follow instructions,
 * Be able to sit on the horse and testing barrel by abduction of the hip,
 * Be available for the duration of the study, specified at 26 weeks.
 * Any significant history of riding horses or participated in this type of therapy prior to this study,
 * Neuromuscular impairments such as cognitive, attentional, sensory or psychosocial
 * Uncorrected visual impairments,
 * Prior surgery or any planned therapeutic surgeries or medical interventions during the length of the study.

What Were the Basic Results?
Beneficial results were shown for children with Cerebral Palsy after the Hippotherapy undertaken in this study. Head angle and movement variability indicating muscular control improved when comparing the results of the pre and post intervention tests. This improvement was also maintained after therapy ceased, between post intervention one and post intervention two. Reduction of anterior/posterior translation and reduced horizontal translation was also seen through video analysis. This was measured by two reflective markers on the head and one on the spine at C7. Head and trunk stability and control were assessed by the amount of movement of the upper portion of the body caused by movement of the pelvis. Functional reach showed to be positively affected by therapy through time taken and Reach Path Ratio (Straightness over distance) decreasing. Although the subjects with Cerebral Palsy were significantly different to the control group, the results showed movement towards normal function after therapy. These beneficial results are also displayed by the children after the Hippotherapy has ceased. After a three month lapse in therapy increased muscular control was still evident through results of post intervention test two.

Conclusions
From the evidence of this research, this type of therapy can be beneficial for children with Cerebral Palsy. Hippotherapy has long been recognised and researched as a therapy for children suffering from this disability. This paper goes a step further by quantifying results over a time period to enable more accurate conclusions to be drawn. This type of therapy has also been shown to have a high compliance rate as it is enjoyable for the participant. This means the child has a high motivation to complete therapy as opposed to a strength and conditioning program in a gym.

Practical Advice
Further research is required on the dose-response relationship of Hippotherapy as this study only explored a once per week intervention. Results showed a movement towards normal function, but it is unclear if this is the absolute extent of improvement obtainable. Recent research that explores twice a week therapy for 24 weeks displays evidence that further improvement in muscular control is achievable. Through exclusion criteria the more severely disabled population was not represented in this study which creates limitations in the results. Overall this study provides beneficial evidence that improvement of functionality of Cerebral Palsy patients is achievable.

Further Resources
For further information on Hippotherapy and Cerebral Palsy, follow the links below;
 * Changes in Trunk and Head Stability in Children with Cerebral Palsy After Hippotherapy - A Pilot Study
 * Comparison Between the Robo-Horse and Real Horse Movements for Hippotherapy Comparison
 * Long-Term Effects of Hippotherapy on One Child with Cerebral Palsy - A Research Case Study
 * The Effects of Hippotherapy on Postural Balance and Functional Ability in Children with Cerebral Palsy