Peri-capsular Nerve Group (PENG) Block and Quadratus Lumborum Block for Hip Arthroplasty

Peri-capsular Nerve Group Block and Quadratus Lumborum Block for Hip Arthroplasty: A Randomized Controlled Trial

The goal of this randomized controlled clinical trial is to compare peri-capsular nerve group (PENG) block and quadratus lumborum (QL) block in participants who receive hip arthroplasty. The main question aims to answer is comparing the pain score among participants who receive PENG or QL block.

Participants will be randomized and assigned into two groups. Participants will receive a PENG block in the PENG group and receive a QL block in the QL group. After participants receive hip arthroplasty, the investigators will compare the two groups to see if there is a difference of pain score, postoperative opioid consumption, sensation and motor function after nerve blocks, progress of functional recovery in lower limbs, intraoperative and postoperative complications.

Hip joint surgery is a common orthopedic procedure that effectively improves patients' quality of life and functional status. However, postoperative pain is a common issue that can affect patients' activity, increase the risk of venous thromboembolism due to venous stasis, and prolong recovery time, hospital stay, and expenses. Therefore, controlling postoperative pain after hip joint surgery is crucial to reduce its side effects. Nerve block is one of the methods for postoperative pain management after hip joint surgery and has been proven effective in reducing pain levels, decreasing opioid use, and its side effects.

Traditionally, the quadratus lumborum nerve block (QL block) is used for pain relief during abdominal surgery, but it can also be used for lower limb surgery due to its extensive application. Compared to other nerve blocks, QL block may provide better postoperative pain relief, have less impact on hip joint activity and quadriceps muscle contraction, and reduce opioid use and hospital stay.

The peri-capsular nerve group block (PENG block) is another nerve block technique performed by injecting anesthetic analgesics around the hip joint capsule using ultrasound and blocking surrounding nerves with a larger dose. In a clinical study, PENG block significantly reduced static and dynamic pain scores in five patients with femoral neck fractures after 30 minutes of the nerve block. PENG block has advantages in injection and identification of anatomical structures compared to QL block, but their analgesic effects have not been directly compared. Therefore, clinical trials of both techniques are needed.

Inclusion Criteria:

• Patients who are 20 years of age or older (including 20 years of age).
• Non-emergency hip arthroplasty surgery.
• Able to understand and cooperate with preoperative and postoperative data collection.
• Grade one to three in the American Society of Anesthesiologists (ASA) physical status classification.

Exclusion Criteria:

• Under 20 years of age.
• A known allergy to the study medication (ropivacaine).
• Liver cirrhosis classified as Child Pugh Score C.
• Dementia or mental illness.
• Unable to assess their own pain level.
• Patients who have been using opioid drugs for a prolonged period.
• Having a history of drug or alcohol abuse within the last 6 months.
• Having serious illness and at a risk of imminent mortality.