A spinal stabilization system may be formed in a patient. In some embodiments, a minimally invasive procedure may be used to form a spinal stabilization system in a patient. Bone fastener assemblies may be coupled to vertebrae. Each bone fastener assembly may include a bone fastener and a collar. Extenders may be coupled to the collar to allow for formation of the spinal stabilization system through a small skin incision. The extenders may allow for alignment of the collars to facilitate insertion of an elongated member in the collars. An elongated member may be positioned in the collars and a closure member may be used to secure the elongated member to the collars. An adjuster may be used in conjunction with the extenders to change a separation distance between the bone fastener assemblies.