Polyaxial adjustment of facet joint prostheses

A method of replacing a facet joint between adjacent vertebrae, the method comprising:

• attaching a first spinal prosthetic member to a first spinal structure, the first spinal prosthetic member comprising a first joint element including a first support arm attachable to a first fixation element, wherein the first fixation element comprises a spherical head and wherein the first support arm is attachable to the first fixation element via a fixing element having a concave surface that rests on top of the spherical head of the first fixation element;
• and
• attaching a second spinal prosthetic member to a second spinal structure, the second spinal prosthetic member comprising a second joint element including a bearing surface and a support structure attachable to a second fixation element via a connection element, wherein the second fixation element has a first longitudinal axis and the support structure has a second longitudinal axis extending through a center of the bearing surface, wherein the support structure is offset from the second fixation element such that the second longitudinal axis does not intersect the first longitudinal axis when the support structure is secured to the second fixation element, wherein the second longitudinal axis is substantially parallel to the first longitudinal axis when the support structure is secured to the second fixation element;
• and
• allowing articulation between the first joint element of the first spinal prosthetic member and the second joint element of the second spinal prosthetic member to form an articulating assembly.