39 Fascia Iliaca Block
The fascia iliaca block is an anterior approach to lumbar plexus block that can result in extensive anesthesia and analgesia of the lower extremity. This block can provide analgesia following hip surgeries involving a lateral incision. Fascia iliaca block also can provide pain relief following hip fracture or be performed to help position a patient for spinal anesthesia prior to surgery. The fascia iliaca block may provide better thigh tourniquet tolerance than isolated femoral nerve blocks. Fascia iliaca injections reliably block the femoral nerve and lateral femoral cutaneous nerve (LFCN). Block of some of the adjacent nerves is also possible (including the ilioinguinal, genitofemoral, obturator, and accessory obturator nerves). Classically, fascia iliaca block is guided by tactile sensation (feeling two pops as a dull block needle is advanced through the fascia lata and fascia iliaca of the thigh).
Suggested Technique
The patient is placed in supine position (flat with slight extension of the hip). Pannus retraction or reverse Trendelenburg position may be necessary in overweight patients. Place the transducer longitudinally to image the iliacus muscle lateral to the femoral nerve. Because of the inclination of the iliacus muscle, this region is slightly more superficial than the femoral nerve. The iliacus muscle forms a ridge because of the underlying bone of the superior pubic ramus. The deep circumflex artery lies superficial to the fascia iliaca 1 to 2 cm proximal to the inguinal ligament. This artery is 2 to 3 mm in diameter and lies on the central side of the iliacus ridge. Tilting the transducer laterally enhances imaging of the fascia iliaca due to its inclination.1
In-plane approach from distal to proximal is used. For this block it is critical that the needle tip be positioned between the fascia iliaca and iliacus muscle,2
