Triple Nerve Injection for Open Reduction and Internal Fixation of Fracture Tibia and Fibula - A Feasibility Study

Targeting femoral, obturator, and sciatic nerves with an anterior approach is a daunting task. Surface landmarks have been described but with limited success. This feasibility study describes a single-puncture approach to the three nerves in real time under the guidance of a curvilinear probe and investigates the feasibility in the proximal thigh for patients undergoing bicondylar fixation with fractures of the proximal tibia.

Forty patients with fractures of the proximal tibia planned for a bicolumnar open reduction and fixation with a plate were recruited in this feasibility study. We named this unique approach the "triple nerve injection" (TNI) block. These blocks were injected with 40 mL of 0.2% ropivacaine injected in the vicinity of the branches of the femoral nerve (10 mL), the sciatic nerve (20 mL), and between the adductors targeting the anterior and posterior division of the obturator nerves (5 mL each).

The pain was perceived at a mean of the 12^th h on the medial side as against a mean of the 13^th h on the lateral aspect. The time to rescue analgesia was 12 h. An optimal spread was visualized in 90% of blocks, while the diffusion in 10% of sciatic blocks was inadequate.

A TNI block facilitates a single-puncture and a single-probe placement technique enables a satisfactory visualization of three fascial planes, together with a single needle redirection.