Evaluation of the Analgesic Benefit of Adding the Blocks of the Intermediate and Medial Femoral Cutaneous Nerves in Addition to the Femoral Triangle Block for Postoperative Analgesia After a Knee Replacement Surgery

Total knee replacement surgery can be associated with a significant postoperative pain burden and an inability to mobilize adequately, which can lead to the failure of the ambulatory course. Indeed, early mobilization is beneficial in this context in order to prevent complications related to immobility. The optimization of postoperative analgesia is therefore a key issue for the success of this intervention in an outpatient setting or during a short-term hospitalization since an adequate pain relief facilitate the earlier mobilization of the operated joint. Modern postoperative analgesia protocols recommend a multimodal approach, including the use of acetaminophen, anti-inflammatories, opioids and others as well as the use of nerve blocks. Some nerve blocks used for total knee replacement surgery, such as the femoral nerve block, do not preserve the motor skills of the operated limb, which may alter the clinical trajectory due to delayed mobilization due to weakening of the quadriceps, one of the extensor muscles of the knee. Currently, one of the blocks used to spare the motor functions is the block of the femoral triangle. Unfortunately, this block of the femoral triangle does not fully cover the skin component of the surgical incision used for a total knee arthroplasty. A solution to obtain a better quality of pain relief at the level of the cutaneous incision would be to add a block of the para-sartorial compartment, which makes it possible to cover the nerve territories not covered by the femoral triangle block. The hypothesis of this study is that the addition of the para-sartorial compartments (PACS) block, which aims to block the intermediate cutaneous femoral nerve, will improve the postoperative analgesia after total knee replacement surgery, compared to the classical isolated approach of the femoral triangle block (FTB).