The purpose of this study is to determine if the method for injecting local anesthesia affects patients' pain and opioid usage after surgery. The investigators will compare subcutaneous anesthesia, injections of anesthesia under the skin, to a method called erector spinae plane block (ESPB). An ESPB injection involves placing local anesthesia along the muscles and bones in the back, using a special type of x-ray called fluoroscopy for guidance. The Investigators will use patient reported outcomes (PROs) and track subjects' opioid usage to find out if there is a difference between ESPB and subcutaneous anesthesia. The investigators hypothesize that patients who get ESPB injections will use less opioids and report less pain after lumbar fusion surgery compared to patients who receive subcutaneous anesthesia injections.

Inclusion Criteria:

• The individual has signed and dated a study specific informed consent form approved by the Institutional Review Board at UMMHC.
• The individual is at least 18 years of age.
• The individual is skeletally mature (over the age of 18).
• The patient is scheduled for a one or two level lumbar spinal fusion.

Exclusion Criteria:

• Patients unable to consent for themselves.
• Pregnant women.
• Non-English speaking subjects.
• Prisoners.
• Spinal fusion procedures for a diagnosis of fracture, tumor, and/or infection.
• Patients who have used greater than 150 morphine milligram equivalents of opioids in the month prior to their operation.
• Patients with a body mass index (BMI) of 40 or greater.

All of the individual participant data collected during the trial will be shared after deidentification.

The data will be available immediately following publication and will remain available for six (6) years.

The data will be provided to researchers who provide a methodologically sound proposal.

Participants will be masked to the treatment arm. The research team (outcomes assessors) involved in evaluation of subjects will be blinded to the treatment arm.