POSTOPERATIVE PAIN IN CANINE ORTHOPEDIC SURGERY: MECHANISMS, ASSESSMENT, AND FUTURE PERSPECTIVES
Keywords:
Canine orthopedic surgery, Postoperative pain, Pain assessment, Multimodal analgesiaAbstract
Postoperative pain remains one of the most significant challenges in canine orthopedic surgery because of its complex pathophysiology and its profound effects on animal welfare, functional recovery, and long-term clinical outcomes. Orthopedic procedures involve extensive trauma to bone, periosteum, muscles, ligaments, tendons, and surrounding soft tissues, initiating a cascade of inflammatory and nociceptive events that may lead to peripheral and central sensitization if inadequately managed. Advances in pain neuroscience have transformed the understanding of postoperative pain from a simple consequence of tissue injury to a multidimensional process involving interactions among peripheral nociceptors, spinal nociceptive pathways, supraspinal modulation, neuroplasticity, and cognitive-emotional mechanisms.
These insights have provided the scientific foundation for contemporary multimodal analgesic strategies aimed not only at relieving pain but also at preventing pain chronification. Accurate pain assessment is fundamental to effective analgesic management but remains particularly challenging in veterinary medicine because animals cannot verbally communicate pain. Consequently, clinicians must integrate multiple complementary assessment methods.
This review summarizes current knowledge regarding the physiological mechanisms underlying postoperative pain following canine orthopedic surgery and critically discusses available pain assessment approaches, including behavioral evaluation, physiological indicators, validated composite pain scoring systems, and objective functional assessment techniques. Recent developments in force plate analysis, pressure-sensitive walkway systems, wearable accelerometers, infrared thermography, heart rate variability, pupillary pain assessment, and integrated nociception monitoring systems are also reviewed, highlighting their clinical applications, advantages, and current limitations.
Finally, the review discusses future perspectives, including molecular biomarkers, wearable technologies, and artificial intelligence-assisted pain recognition, which are expected to improve the objectivity and precision of postoperative pain assessment. Collectively, current evidence supports a multimodal approach integrating behavioral, physiological, functional, and emerging objective indicators to optimize postoperative analgesia, improve rehabilitation, and enhance the quality of life of dogs undergoing orthopedic surgery.
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