Postoperative Pain Control Using Local Wound Infiltration in Adolescent Idiopathic Surgery

Postoperative Pain Control Using Local Wound Infiltration in Adolescent Idiopathic Surgery: A Randomized Control Trial

Non-opioid methods of pain management following posterior spinal fusion (PSF) have become increasingly popular given the rise of opioid abuse and opioid-related deaths. Orthopedic surgery remains one of the highest prescribing subspecialties. Local wound infiltration is an effective method of acute pain management following surgical intervention and is the standard in some surgical subspecialties, however, no randomized control trials (RCT) exist in the pediatric spine literature. This would be the first (RCT) to assess the use of local would infiltration in postoperative pain control following PSF for adolescent idiopathic scoliosis patients (AIS). The primary aim of this study is to investigate the efficacy of local wound infiltration with anesthetic agents in reduction of postoperative pain scores and post-operative opioid use during hospital admission following fusion surgery in AIS patients. The proposed single-center, double-blind prospective randomized study will be conducted by recruiting patients meeting the inclusion criteria of age 10-26 years and diagnosis of AIS undergoing posterior fusion surgery. Study participants will be randomized into either a local injection of 0.25% bupivacaine with epinephrine or a placebo of equal volume injectable saline. Patient-reported outcomes will be collected at 1-, 6-, 12- and 24-months postoperatively.

The local infiltration will occur in 2 stages, separated by 30 minutes. The first dose will be injected just prior to the final tightening of set screws, decortication, and bone grafting, and will occur via multiple small volume injections 1 centimeter apart into the paraspinal musculature. The second injection will occur at an interval of 30 minutes following deep fascial closure and similarly consist of multiple small volume injections at 1 centimeter intervals into the subcutaneous tissue and skin.

An equal volume of injectable saline will be used in the exact 2 stages as the treatment group. The first dose will be injected just prior to the final tightening of set screws, decortication, and bone grafting, and will occur via multiple small volume injections 1 centimeter apart into the paraspinal musculature. The second injection will occur at an interval of 30 minutes following deep fascial closure and similarly consist of multiple small volume injections at 1 centimeter intervals into the subcutaneous tissue and skin.

The average Visual Analog Scale pain score (on a scale of 0-100 mm) during the first 24 hours postoperatively will be computed from at most six values typically obtained every four to six hours following surgery. The higher the score, the higher the experienced pain of the individual.

The average use of morphine equivalents per kilogram during the first 24 hours postoperatively. Morphine equivalents per kilogram will be also be obtained by reviewing post-anesthesia care unit reports.

SRS-30 scores at 1-, 6-, and 12-months post-operatively. The Scoliosis Research Society (SRS-30) questionnaire is a 30-question patient reported instrument developed to evaluate health-related quality of life in patients with scoliosis. Scores from the SRS-30 are compiled into five domain scores: pain, function, self-image, mental health and satisfaction with management of scoliosis. Each domain score is reported on a scale form 1-5. The lower the score, the worse the outcome.

Inclusion Criteria: ≥10 years old and ≤17 years old at assessment Diagnosis of Adolescent Idiopathic Scoliosis (AIS) Planned surgical treatment of progressive spinal deformity with posterior spinal fusion Exclusion Criteria: Diagnosis of neuromuscular, syndromic, or congenital scoliosis History of known allergy to local anesthesia Chronic pre-operative opioid consumptions Any other analgesic treatment for chronic pain before surgery Psychiatric or neurological disorders Cannot fluently read or speak English