The realm of manual therapy includes diverse techniques such as chiropractic, osteopathy, physical therapy, massage therapy, and touch therapies, which have been developed for use in human beings and the techniques transferred to horses. All forms of manual therapy have reported levels of effectiveness for treating musculoskeletal issues in human beings, but mostly only anecdotally evidence exists in horses. The purpose of this review is to explore the scientific literature for potential common mechanisms of action and evidence of efficacy and safety for different forms of manual therapies, with a specific focus on joint mobilization and manipulation techniques. A description of a detailed musculoskeletal and spinal examination using manual therapy techniques is also presented. In humans, there is an extensive published data base for most forms of manual therapies; however, the methodological quality of most studies is poor, which often prevents definitive conclusions and recommendations. In horses, there are too few controlled studies to support most anecdotal claims of effectiveness. However, there is limited evidence suggesting effectiveness of spinal manipulation in reducing pain and muscle hypertonicity and increasing joint range-of-motion. Further research is needed to assess the efficacy of specific manual therapy techniques or combined treatments for management of documented back problems and specific lameness conditions in horses. Additional studies are also needed to define specific treatment parameters required for optimal management of select disease processes, such as the amount of force applied, and the frequency and duration of treatment.
Effects of manipulative therapy on the longissimus dorsi in the equine back
Pain, atrophy and dysfunction of the longissimus dorsi in the equine back can lead to poor performance and altered biomechanics. Back problems are often treated by manipulative therapy to this muscle. The purpose of this study was to identify if manipulative therapy resulted in changes to muscle tone or electromyographic EMG) activity immediately after treatment. We measured the muscle tone during standing using a mechanical tissue indenter and the EMG activity (both at the T16 level in the longissimus dorsi) during walking around a figure-of-eight course in 26 horses. The horses were randomly assigned into three groups that received: (a) spinal (McTimoney) manipulations, (b) reflex inhibition therapy or (c) a control group that was not manipulated. The muscle tone and activity were measured immediately after treatment. Both the McTimoney and the reflex inhibition groups showed significant decreases in muscle tone (c. 12%) and walking EMG activity (c. 19%). The control group showed no significant change in tone or EMG activity. These results document how the longissimus dorsi muscle responds immediately after manipulative therapy. Further studies would be needed to identify how long such changes persist or if such changes caused a reduction in pain or an increase in performance.
Equine Manual Therapies in Sport Horse Practice
Manual therapies involve the application of the hands to the body, with a diagnostic or therapeutic intent. In horses, a diverse array of manual techniques, such as touch therapies, massage, joint mobilization, and manipulation (ie, chiropractic), have been applied with a primary therapeutic intent (eg, reduce pain or stiffness).1–3However,all of these therapies also have important diagnostic value in assessing musculoskeletal pain and dysfunction that is not possible with other more traditional physical ex-amination approaches or imaging modalities. In sport horse practice, the primary issues that limit performance are chronic repetitive use injuries associated with long active athletic careers of pushing physical and psychological limits of horse and rider. Chronic, poorly localized pain and stiffness combined with slower reflexes or altered muscle timing contribute to poor performance issues and increase the risk of acute injury and inflammation. Manual therapies can provide detailed soft tissue, osseous, and articular evaluation techniques and unique methods to assess neuromuscular coordination and strength in sport horses that are not possible with routine lameness evaluation or neurologic tests.