(plaintiff, horse rider, sued equestrian center after she lost control of horse which tripped on training poles and threw plaintiff resulting in plaintiff’s injuries; plaintiff’s expert opinion was that placement of poles and movable step was negligent, trial court held that plaintiff’s injury result of inherent risk of equine activity and that plaintiff’s claim barred by Equine Act; appellate court reversed on basis that the negligent disregard of participant’s safety rule of exception to exemption from liability under Equine Act might apply and that summary judgment not appropriate; Supreme Court reversed, reinstating judgment of trial court – poles and step not faulty).