Psoas compartment block

Psoas compartment block (PCB) is a peripheral regional anaesthetic technique that blocks the main components of the lumbar plexus, namely the femoral, lateral femoral cutaneous (LFC), and obturator nerves as they run within the psoas major muscle. The psoas compartment block is also known as the posterior lumbar plexus block. A posterior approach to the lumbar plexus was first described by Winnie and colleagues. They described an approach for ‘lumbosacral’ block but provided no data on the extent of neural block. The term ‘psoas compartment block’ was coined by Chayen and colleagues to describe a loss of resistance technique with injection of solution into the ‘compartment’ between the quadratus lumborum and psoas major muscles. There have been a number of other approaches described since, including an approach by Capdevila and colleagues based on modifications to Winnie’s landmarks using computed tomography.