Patients enrolled in the study group will receive a PENG block with 20 mL of 0,375% levobupivacaine with 4 mg of dexamethasone. The block will be performed with the patient in a supine position using an 18-gauge, 90 mm needle, inserted with an in-plane lateral to medial approach. Operators will use the original technique described by Girón-Arango L et al. The aim of this block is to inject the local anaesthetic between the psoas tendon and the iliopubic eminence. We will instruct operators to routinely use a curvilinear probe (2-6 MHz) or a linear probe (4-16 MHz) in particularly lean or cachectic patients.

Patients allocated in the control group will receive an infrainguinal fascia iliaca block with 30 mL of 0,25 % levobupivacaine with 4 mg of dexamethasone, using an 18-gauge, 90 mm needle, inserted with an in-plane lateral to medial approach. The probe (linear 4-16 MHz) is placed transversely at the inguinal crease to identify the femoral artery, femoral nerve, iliopsoas muscle and the fascia iliaca over the psoas muscle. Moving the probe laterally the sartorius muscle and the anterior inferior iliac spine (AIIS) can be identified. After skin disinfection the needle is inserted placing the tip beneath the fascia iliaca at the lateral third of a line between the AIIS and pubic tubercle. Correct needle placement is confirmed by separation of the fascia iliaca from the iliopsoas muscle upon injection, with local anaesthetic spreading towards the FN medially and the iliac crest laterally.