Abstract
The evolution of regional anesthesia in total hip arthroplasty (THA) has significantly impacted perioperative management, particularly in older adults, where age-related physiological vulnerability requires optimized strategies. Adequate pain control is crucial in enhancing recovery, minimizing opioid consumption, and reducing complications. Traditional nerve blocks such as lumbar plexus and femoral nerve blocks have long been the mainstay of analgesia. However, they are associated with significant motor impairments, which delay mobilization and increase the fall risks. Introducing motor-sparing regional anesthesia techniques represents a substantial advancement in optimizing postoperative pain management while preserving muscle function. Motor-sparing techniques, including the pericapsular nerve group (PENG) block, supra-inguinal fascia iliaca block (SI-FIB), erector spinae plane block (ESPB), and quadratus lumborum block (QLB), have been developed to provide adequate analgesia without compromising motor control. The PENG block selectively targets the articular branches of the femoral, obturator, and accessory obturator nerves, ensuring superior pain relief while minimizing quadriceps weakness. Similarly, the SI-FIB provides extensive sensory blockade with minimal motor involvement, allowing for earlier ambulation. The ESPB and QLB extend analgesia beyond the hip region while preserving motor function, reducing opioid consumption, and facilitating early rehabilitation. Compared to traditional motor-impairing blocks, these newer techniques align with Enhanced Recovery After Surgery (ERAS) protocols by promoting early mobility and reducing the hospital length of stay. Studies suggest that motor-sparing blocks lead to improved functional recovery, lower postoperative pain scores, and decreased opioid requirements, which are critical factors in geriatric THA patients. Moreover, these techniques present a safer alternative, reducing the risk of postoperative falls-a significant concern in elderly patients undergoing hip replacement. Despite their advantages, motor-sparing nerve blocks are still evolving, and further research is necessary to standardize the protocols, optimize the dosing strategies, and evaluate the long-term functional benefits. Integrating these techniques into routine perioperative care may significantly enhance patient outcomes and revolutionize pain management in geriatric THA. As regional anesthesia advances, motor-sparing techniques will improve postoperative recovery, ensuring patient safety and functional independence.