Magnetic resonance imaging of distribution of injectate after two approaches for psoas compartment block

Abstract

Introduction Magnetic resonance imaging (MRI) provides excellent visualisation of distribution of injectate after peripheral nerve blocks. The aim of this study was to investigate the distribution of contrast media after psoas compartment block (PCB) performed via two approaches.Methods: Four volunteers were enrolled in a cross-over study.Volunteers underwent PCB with catheter placement performed via Capdevila's approach followed one week later by PCB performed as per Winnie's approach. MRI of contrast distribution was performed after each PCB. Images were subsequently reviewed by a radiologist unaware of PCB approach used.

Psoas compartment block

“…5 Lumbar plexus block occurs after spread of solution within the fascial plane with cephalad spread to the lumbar roots. 6 In 25% of cases, block of the first sacral root also occurs and in 70% of cases an ilioinguinal/iliohypogastric block is found. 7…”

“…along the internal fascial plane, surrounding the lumbar branches with cephalad spread to lumbar nerve roots. 6 The introduction of solution within the fascial plane results in cleavage of the psoas muscle, facilitating the distribution of solution to the lumbar nerve roots ( Fig. 1).…”