Hybrid Blocks for Total Knee Arthroplasty: A Technical Description.

Introduction:This narrative review article aims to examine current evidence of knee innervation in order to develop a technique of targeting pure sensory innervation of the knee joint without compromising motor function.Methods:A literature review of knee innervation was performed to gain an anatomic understanding of terminal sensory branches of the relevant target nerves (femoral, obturator, sciatic, and lateral femoral cutaneous).Results:Pure sensory block of the knee joint is challenging due to important contributions from themuscular innervation close to the joint and the variability of nerves afferents contained within and around the adductor canal.Conclusion:On the basis of this anatomic knowledge we describe an ultrasound-guided 3-injection hybrid technique that represents a balance between preserving adequate motor power while still providing analgesia in a simple method.