A double-jointed bone bolt for use in an apparatus for maintaining vertebra in a desired relationship. The apparatus has a rod that extends substantially along the spine and one or more bone bolts. At least one of the bone bolts is double jointed. The double-jointed bolt has a mounting portion with a hook or coarse threads to engage a vertebra, and the mounting portion is attached to a pivot post in a manner that allows the pivot post to be rotatable about a common axis in respect to the mounting portion. The pivot post of the bone bolt is then pivotally attached to a connector portion of the bone bolt that has machine threads upon which a surgeon may attach a clamp. The clamp has a second bolt and an arm. The second bolt holds the rod and the arm to the clamp. The second bolt has a first channel to attach to the rod, while the arm has a second channel to attach the double-jointed bone bolt.
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