This initial study is a feasibility study for implementing thoracolumbar interfascial plane, or TLIP, blocks in older adults undergoing spinal fusion. TLIP blocks are done by using anesthesia. In this case, it will be done to either side of the back where surgery will be performed. This has been shown to decrease pain the patients have post-operatively in previous research. In this study, the investigators will examine recruitment rates, completion of assessments, dropout rate, gather patient feedback, and identify barriers to performing TLIP. Further, this feasibility study will provide data to determine adequate sample size and refine methods and outcomes for a future randomized clinical trial. The ultimate goal is to perform a large, appropriately powered randomized control trial to determine the effect of TLIP blocks on pain, physical function and disability, opioid consumption, and delirium in older adult undergoing spinal fusion.