Pericapsular Nerve Group Block

Hip and knee surgeries are common among older patients. In 2010, the prevalence of total hip replacement in the United States was 0.58% at 50 and increased to 5.26% at 80. A recent study in the United States projected that compared to 2010, the annual use of primary knee and hip total joint arthroplasty could increase by 210% (655K to 1375K) and 174% (293K to 512K) in 2020. In 2015, the prevalence of total hip arthroplasty was estimated at more than 2.5 million individuals in the United States. Osteoporosis and osteoarthritis are significant contributors to the need for surgery. However, a wide range of patients require hip surgery, including children with congenital hip dysplasia, young athletic adults undergoing hip arthroscopy, and frail older patients with multiple medical problems experiencing traumatic accidents following mechanical falls. Approximately 7% to 28% of patients develop chronic pain after hip surgery. Regional anesthesia significantly benefits pain management and recovery in patients undergoing total hip arthroplasty. A variety of regional anesthetic techniques are commonly used. The most frequently used methods in this anatomical area and the most supported by published literature are the lumbar plexus, femoral nerve, and fascia iliaca blocks. Alternative techniques include selective obturator nerve infiltration and lateral femoral cutaneous nerve blocks. New approaches, such as quadratus lumborum block and local infiltration analgesia, have also been described. However, these techniques require future studies. A recent anatomical study on hip innervation has identified the landmarks targeted on the hip joint branches from the femoral and accessory obturator nerve. Thus, a new regional anesthesia technique identified as the pericapsular nerve group (PENG) block has emerged. This technique targets the anterior capsule of the hip by blocking these nerves. The PENG block, first described by Girón-Arango et al, is a novel regional analgesia technique used to reduce pain after total hip arthroplasties while sparing motor function. This technique involves the deposition of the local anesthetic in the fascial plane between the psoas muscle and superior pubic ramus. This interfascial plane block aims to block articular branches supplied by femoral, obturator, and accessory obturator nerves. This regional anesthetic technique is a promising alternative to other regional nerve blocks, such as femoral nerve or iliac fascia nerve blocks.