Depomedrol for Genicular Nerve Block.

TKA remains a challenge for physicians as more than half of these patients experience extreme knee pain immediately after surgery. The management of pain in patients undergoing total knee arthroplasty (TKA) remains a challenge for the anesthesiologist even with regional anesthesia as no single regional technique is adequate to balance effective analgesia with minimal muscle weakness. Severe postoperative pain following TKA has been shown to negatively affect early mobilization, physical rehabilitation, time to discharge, and overall post-op recovery. Multimodal analgesia incorporating regional anesthesia techniques provides optimum analgesia and minimizes the use of opioids and their side effects. Proximal nerve blocks such as the lumbar plexus, femoral nerve, and proximal sciatic nerve blocks provide excellent analgesia but frequently cause motor weakness, which reduces the patient's mobility. A distal blockade of genicular branches has also been described using ultrasound in acute and chronic pain management with fewer side effects. The superior medial genicular nerve and lateral genicular nerve can be identified using ultrasound and blocked at the level of the medial intramuscular, and lateral femoral epicondyles deep to the vastus medialis and lateralis, respectively. The inferior medial genicular nerve can be also targeted medial to the tibial plateau adjacent to the genicular vessels. Methylprednisolone acetate (MPA)(Depomedrol) is a lipophilic glucocorticoid commonly used in chronic pain procedures. It has a good safety record and its analgesic action can last from days to weeks.(8) The literature supporting its role as an adjuvant to local anesthetic in peripheral nerve block are scanty. However, some studies showed that depo-methylprednisolone as an adjuvant to 0.5% lidocaine showed excellent results in neuropathic pain resulting from nerve injury. This study aims to evaluate the efficacy of adding depomedrol as an additive to bupivacaine in genicular nerve block for evaluating postoperative pain, opioid use, and ease of ambulation in patients undergoing TKA.

Inclusion criteria

• Subjects scheduled for primary elective total knee arthroplasty.
• American Society of Anesthesiologists Physical Status I-III.
• BMI 18-35 kg/m2.

Exclusion criteria

• Bleeding disorders.
• Allergy to any of the drugs used in the study.
• Renal insufficiency.
• Liver failure
• Neurological abnormalities (uncooperative or psychologically unstable patients).
• Patient refusal.
• Contraindication to a peripheral nerve block.
• ASA IV or V.
• Skin lesions/infection at block site.