Analgesic Efficacy of Mid-Transverse Process to Pleura (MTP) Block and Intrathecal Morphine in Idiopathic Scoliosis Patients Undergoing Posterior Spinal Fusion

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.