Comparison of Ultrasound Guided Genicular Nerve Block and Periarticular Infiltration in Knee Arthroplasty

Total knee arthroplasty (TKA), one of the most commonly performed operations in orthopaedic department, has been a successful intervention for patients with end-stage knee arthritis.

Rehabilitation after total knee arthroplasty (TKA) routinely starts immediately after surgery on the postoperative ward and therefore requires adequate analgesia. An ideal analgesic modality for post-TKA rehabilitation should permit adequate knee flexion with minimal pain without motor impairment, resulting in successful mobilization. Pain control plays an essential role in the overall postoperative period for the patients undergoing TKA.

Effective pain relief allows the patients to obtain early knee mobilization and optimal rehabilitation and thus improves the patient satisfaction.

The aim of perioperative pain control is to minimize delays in recovery, postoperative delirium and pain-related stress responses that can lead to serious morbidity and poor outcomes. Numerous approaches to effectively control postoperative pain in TKA patients have been evaluated, as poorly controlled acute postoperative pain can be associated with persistent pain. Furthermore, increased pain intensity after surgery on the second knee seems to be closely associated with chronic post-TKA pain, with similar mechanisms underlying hyperalgesia or chronic pain.

Traditionally, the degree of knee flexion has been used as an outcome measure after TKA to evaluate functional recovery and the success of the type of analgesia used.

Several methods such as intravenous opioids, extraarticular and intraarticular injection, epidural analgesia and femoral or sciatic nerve blocks are currently used for postoperative pain management.

However, each method is reported with potential side effects, for example, opioid drugs caused vomiting, nausea, constipation, dizziness and urinary retention, epidural analgesia with urinary retention, respiratory depression and spinal headache, femoral or sciatic block with diminished muscle control and possible nerve damage.

Periarticular multimodal drug injection in TKA is a technique that patients received intraoperative drug injection in the periarticular fields such as posterior capsule, medial and lateral collateral ligaments, quadriceps mechanism and peripatellar tissue at the end of the surgery. Multimodal drugs mainly consist of local anaesthetics, non-steroidal anti-inflammatory drugs, opioids, epinephrine with or without corticosteroid.

Genicular nerve block (GNB) and ablation have been used for managing chronic pain from knee osteoarthritis with good success.