Abstract
Total knee replacement is a common surgical procedure associated with significant postoperative pain, which can delay recovery and increase healthcare costs. Regional anesthesia techniques, including local infiltration analgesia and fascial plane blocks, play a crucial role in multimodal pain management strategies. These approaches aim to enhance pain relief while minimizing opioid use and preserving motor function. This narrative review evaluates the effectiveness and safety of motor-sparing fascial plane blocks for total knee replacement, categorizing techniques based on their anatomical target areas: anterior, posterior, and other approaches. A comprehensive literature search was conducted using databases such as MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. The search included studies on motor-sparing regional anesthesia techniques for total knee replacement using relevant keywords such as "regional anesthesia," "peripheral nerve block," "motor-sparing techniques," and specific block names. The selection criteria included randomized controlled trials, systematic reviews, meta-analyses, and relevant case studies. The techniques were analyzed based on their effectiveness in pain relief, impact on motor function, and overall contribution to enhanced recovery after total knee replacement. The review highlights that the most evidence-supported technique for anterior knee pain management is the block targeting the adductor canal, which provides effective analgesia while preserving motor function. For posterior compartment pain relief, the infiltration between the popliteal artery and the knee capsule is the preferred approach. Emerging techniques, such as the dual subsartorial block and the para-sartorial compartment block, show promise but require further validation. The review also underscores the importance of integrating different techniques to ensure adequate pain control for both the anterior and posterior compartments, facilitating early mobilization in fast-track recovery protocols. Achieving optimal postoperative pain management after total knee replacement requires a combination of targeted regional anesthesia techniques. Current evidence supports the use of adductor canal block for anterior knee analgesia and the infiltration between the popliteal artery and the knee capsule for posterior pain relief. While newer techniques show potential, further research is needed to validate their efficacy and safety. Future studies should focus on refining fascial plane block strategies to optimize analgesic benefits while minimizing motor impairment, thereby improving functional recovery and reducing the reliance on opioid medications.