Circum-Psoas Blocks Versus Combined Lumbar and Sacral Plexus Blocks in Hip Fracture Surgery

The acetabulum and the head of the femur combine to produce a traditional ball and socket joint in the hip. Both the lumbar (L1-L4) and sacral (L4-S4) plexuses innervate the hip joint, and its sensory innervation is from the femoral (FN), obturator, and sciatic nerves with contribution from superior gluteal nerve and nerve to quadratus femoris. Cutaneous innervation is by lateral femoral cutaneous (LFCN), subcostal iliohypogastric nerve, and the superior cluneal nerves which predominately arise from the dorsal rami of L1.

Hip fracture is a major worldwide public health problem in elderly patients aged 65 years and over with an incidence of more than 1.6 million worldwide each year. Furthermore, the total number is expected to exceed 6 million by 2050. Generally, early surgical repair within 48-72 hours after admission is recommended according to the treatment guideline, however, elderly patients with hip fractures commonly have several comorbidities, which make these patients more liable to a high risk of morbidity and mortality after surgery. Pain, both before and during the first 24 hours of surgery is usually reported as severe by most patients therefore, one of the keys to a patient's recovery following hip fracture surgery, is effective postoperative pain management. Recently, the concept of pain relief with multimodal analgesia and regional anesthesia plays a vital role in postoperative analgesia minimizing opioid consumption and reducing the time to early mobilization. The acetabulum and the head of the femur combine to produce a traditional ball and socket joint in the hip. The lumbar (L1-L4) and sacral (L4-S4) plexuses both innervate the hip joint, and its sensory innervation is from the femoral (FN), obturator, and sciatic nerves with contribution from superior gluteal nerve and nerve to quadratus femoris. Cutaneous innervation is by lateral femoral cutaneous (LFCN), subcostal iliohypogastric nerve, and the superior cluneal nerves which predominately arise from the dorsal rami of L1.

Hip fracture is a major worldwide public health problem in elderly patients aged 65 years and over with an incidence of more than 1.6 million worldwide each year. Furthermore, the total number is expected to exceed 6 million by 2050. Generally, early surgical repair within 48-72 hours after admission is recommended according to the treatment guideline, however, elderly patients with hip fractures commonly have several comorbidities, which make these patients more liable to a high risk of morbidity and mortality after surgery. Pain, both before and during the first 24 hours of surgery is usually reported as severe by most patients therefore, one of the keys to a patient's recovery following hip fracture surgery, is effective postoperative pain management. Recently, the concept of pain relief with multimodal analgesia and regional anesthesia plays a vital role in postoperative analgesia minimizing opioid consumption and reducing the time to early mobilization. Several regional anesthetic techniques have been recommended, including intrathecal morphine, patient-controlled epidural analgesia, and various peripheral nerve blocks techniques; however, to obtain complete sensory loss for hip fracture surgery, it's required to block the branches of both lumbar and sacral plexuses, although there remains no single technique that reliably acquires this. Moreover, each of these techniques has specific limitations that prevent them from being the analgesic technique of choice for hip fracture surgery.

The ultrasound-guided lumbar plexus block results in the blockade of the FN, LFCN, and obturator nerve while the sacral plexus block results in the blockade of the sciatic nerve, superior and inferior gluteal nerves, posterior cutaneous nerve of the thigh, and the inferior hypogastric plexus. Thus, the combination of lumbar plexus and sacral plexus blocks results in complete analgesia of the ipsilateral lower limb in the perioperative period.

Circum-psoas blocks is a new sonar-guided fascial block technique proposed by Huili et al., where the two main branches of the lumbar plexus (FN and LFCN) can be blocked by local anesthetic (LA) injection posterior to transversalis fascia (TF) and around the anterolateral edge of psoas muscle (PM) just cranial to iliac crest. Furthermore, cranial spread along TF may lead to a lower thoracic paravertebral block through the medial arcuate ligament. On the other hand, the obturator nerve and lumbosacral trunk could be blocked if the LA is injected at the level of L5/S1 into the retro-psoas space and around the posterior edge of PM.

Our study will be designed to evaluate and compare the impact of combined lumbar and sacral plexus blocks and circum-psoas blocks for sensory level and achievement of postoperative analgesia for patients undergoing hip fracture surgery under general anesthesia.

• Assess sensory block levels [Time frame: at 2 hours postoperatively]
• Total dose of rescue analgesia [Time frame: in the first 24 hour postoperatively]