The aim of this study is to compare the analgesic efficacy of mid-transverse process to pleura (MTP) block and intrathecal morphine in idiopathic scoliosis patients undergoing posterior spinal fusion surgery.

The postoperative period for idiopathic scoliosis patients undergoing posterior spinal fusion (PSF) is fraught with challenges, including adequate postoperative pain control and prolonged hospitalization.

Intrathecal opioids have been used to manage postoperative pain in pediatric patients for a wide variety of surgeries , including adolescent and adult PSF. Multimodal analgesic (MMA) regimens using several drugs and techniques are considered to be necessary for postoperative pain relief.

The mid-transverse process to pleura (MTP) block was first described as a modified paravertebral block in 2017. The local anesthetics (LAs) are administered between the transverse process and the pleura. This results in a LA spread to the dorsal and ventral rami in the paravertebral space through the fenestrations in the superior costotransverse ligament at the level of injection, and frequently to adjacent levels.

Inclusion Criteria:

• Age ≥ 18 years.
• Both sexes.
• American Society of Anesthesiology (ASA) physical status I-II.
• Idiopathic scoliosis patients undergoing posterior spinal fusion surgery.

Exclusion Criteria:

• Patient with morbid obesity (body mass index >40 kg/m2).
• Patients with pre-existing infection at block site.
• Known allergy to study drugs.
• Coagulation disorder.
• History of psychiatric illness.
• Pre-existing neurological deficits.
• Presence of any pre-operative pain or history of chronic pain.
• History of regular analgesic.

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

After the end of study for one year.

The data will be available upon a reasonable request from the corresponding author