An orthopedic stabilization system of implants that includes a bone attachment means that provides poly-axial fixation of the system to the vertebrae, and a connector means that connects the bone attachment means to the spinal rod in a fashion that allows variable height adjustment of the spinal rod (dorsal in the case of posterior spinal pedicle fixation). The orthopedic stabilization system includes a locking means with a tightenable ball-joint arrangement that locks a post means to the bone attachment means in a desired relative spatial orientation. Several embodiments are disclosed, some using traditional mechanical locking means such as screw fasteners, taper-locking interfaces and collets. Embodiments are described that use the austenitic transformation of shape memory alloy (SMA) material to effect a locking of both the ball-joint arrangement and the connector means.
