Pericapsular Nerve Group Block Versus Lumber Erector Spinae Plane Block for Pain Management After Total Hip Arthroplasty

Pain is a major problem that has to be dealt with in case of hip fracture, as it presents an obstacle for examination, positioning for receiving neuroaxial anesthesia and postoperative mobility and physiotherapy. With the introduction of ultrasound in regional anesthesia and peripheral nerve blocks, regional analgesia float to the surface as a substitute for opioids with less side effects Lumbar erector spinae plane block has emerged as a reliable analgesic option for primary total hip arthroplasty (THA). In 2018, a new block was described, termed pericapsular nerve group block or PENG block, that selectively targets the articular branches of the femoral and obturator nerves while sparing their motor components The pericapsular nerve group (PENG) block is an ultrasound-guided approach first de-scribed by Giron-Arango et al. for the blockade of the articular branches of the femoral (FN), obturator (ON) and accessory obturator (AON) nerve that provide sensory innervation to the an¬terior hip capsule. It has been developed as an alternative regional anesthesia technique for the management of acute pain after hip fractures, but its applications are expanding.

Currently, the PENG block has been used to control and reduce pain in hip-related procedures.

There are reports of PENG blocks used as surgical anesthetic techniques for hip arthroplasty (in combination with local anesthetic and intravenous analgesics) or hip arthroscopy (in combination with lateral femoral cutaneous nerve [LFCN] block). There is a report of a PENG block used as analgesic technique for sickle cell disease vaso-occlusive crisis and a PENG radiofrequency ablation for osteoarthritis analgesia. There are also reports about the use of a PENG block for non-hip related interventions, such as leg vein ligation and stripping, medial thigh surgery, prevention of adductor muscle spasm during transurethral resection of bladder and below-knee amputation in association with popliteal sciatic nerve block.These latter cases further extended the application of the PENG block beyond the hip-related area.

So far, most of the reports describe preoperative or postoperative single-shot blocks, while there are only few case reports of continuous PENG blocks.

Due to the novelty of this technique, there are still ongoing debates about the best injection point as well as the best anesthetic concentration and the total volume to be injected.