Effect of Different Truncal Blocks Under Ultrasound-Guidance on Pain Management After Open Reduction of Pediatric Developmental Dysplasia of the Hip: a Randomized Trial

With the patient in a supine position, the needle is advanced from the anterior using an in-plane technique. A linear ultrasound probe is orientated transversely over the lateral abdomen between the iliac crest and the costal margin. Local anesthetic is injected to separate the transversalis fascia from the transversus muscle. The correct needle position was confirmed by injection of 2 ml of normal saline solution that was spreading anterio-posteriorly between the anterior border of QLM and its fascia, in addition to a minimal anterior spread in TAP plane. After negative aspiration, 0.8 ml/Kg of ropivacaine 0.3%was injected.

The needle is directed in the posterior to anterior orientation with the practitioner standing behind the patient. The triangular quadratus lumborum (QL) muscle is adherent to the apex of the transverse process of L3 vertebra. Using the Shamrock method, the needle penetrates the QL muscle with an in-plane approach from the posterior side of the ultrasound probe. The target point is the inter fascial plane between the QL and the psoas major muscle just deep to the transversalis fascia, in order to lessen the risk of unintentional penetration of the peritoneal cavity contrary to the technique. The correct needle position was confirmed by injection of 2 ml of normal saline solution that was spreading anterio-posteriorly between the QL and the psoas major muscle. After negative aspiration, 0.8 ml/Kg of ropivacaine 0.3%was injected.