Pedicle and non-pedicle based interspinous and lateral spacers have an upper surface configured for engagement with an inferior surface of a fifth 
lumbar vertebral body, and a lower surface configured for engagement with an outer surface of a 
sacrum. One configuration includes a component having two opposing 
upper arms and two opposing lower arms. The spacer component has two ends and a central section, each end of the spacer component being configured for attachment to a respective one of the two opposing 
upper arms, and the central section of the spacer has a height configured for placement between a 
spinous process of a fifth 
lumbar vertebral body and a superior surface of an uppermost 
spinous process of a 
sacrum. The ends of the spacer component may be attached to the 
upper arms using pedicle screws, or may use snap-and-lock or other connectors. The two lower arms may either engage directly with the outer surface of a 
sacrum on either side of a medial 
ridge, or may interconnect with a separate component also having two lower arms that engage with the outer surface of a sacrum on either side of a medial 
ridge. Such arms are preferably bent outwardly and include inward serrations to engage with the outer surface of a sacrum on either side of a medial 
ridge. Other configurations include a spacer component that engages with a sacral notch.