An Investigation of Relationships between Horse and Rider Pelvic Asymmetry

Introduction Asymmetry of the horse and rider partnership is a challenging and complex area. There is limited scientific research regarding the occurrence of misalignments in the horse and rider, and if there is any relationship between the two. This study investigated asymmetry of single horse and rider combinations focusing on pelvis asymmetry. Methods 14 single horse/rider combinations (minimum 6 month partnership) on the same daily routine were assessed. Horses and riders were assessed for misalignments of the pelvis, spine, and neck by a fully qualified human and animal (McTimoney) practitioner on the same day. Triplicate measurements of rider dorsal iliac crest (IC) distance (nearest 0.2 cm) and degree of tilt (0d.p) were recorded, sitting and standing, using a PALM palpation meter to calculate IC height discrepancy. Triplicate horse tuber coxae (TC) heights (nearest 0.5 cm) were measured using a plumb line. Difference between means indicated direction and value of asymmetry relative to symmetry of zero. Student's t-test and Pearson's Product Moment correlation examined asymmetry relationships. Results Mean rider IC height discrepancy, standing, was 0.89 ± 0.64 cm and sitting, 1.00 ± 0.66 cm. Mean TC height discrepancy was 1.3 ± 1.6 cm. Asymmetry of the pelvis was a feature of 93% of horse/rider combinations, 85% occurring in the same direction. There was a significant positive correlation between horse TC and rider IC height discrepancies (r2 = 0.4, F = 8.24, P = 0.014). Conclusions This study provides positive evidence of a relationship between the direction of horse pelvic rotation and rider pelvic tilt and also between the degree of tilt and rotation. This has implications for physical therapy treatment of horse and rider. Further research of causal effect relationships of the asymmetries is recommended. Ethical Animal Research Procedures were reviewed by the McTimoney Chiropractic College Ethical Review Committee. Sources of funding: none. Competing interests: none.