Osteotomy instrument

An osteotomy instrument 10 for compression and/or distraction spinal procedures comprising a first leg 100 and a second leg 130 pivotally attached to the first leg 100. Each leg comprises a proximal portion 110, distal portion 120 with distal end 122 and a pocket 123 disposed within the distal end 122. The distal portion 120 of each leg is configured to rotatably engage a bearing member attached to a spine of a patient. The pocket 123 may be generally hemispherical and may have an inner surface configured to engage the bearing member and form a ball in socket joint. The instrument may comprise a locking mechanism 180 comprising a plurality of teeth 186. A temporary rod is also provided for use with a bone screw assembly. An osteotomy instrument kit is also provided comprising an osteotomy instrument and a first bearing member. A method of compressing at least two vertebrae of a spine together is also provided.