Precision treatment of the knee: evolution and prospects from structural repair to functional remodeling

Precision treatment of the knee is moving from structural repair toward deep integration of functional remodeling and individualized decision-making. In the field of sports medicine, anterior cruciate ligament reconstruction enables submillimeter-level positioning of bone tunnels based on multimodal image fusion and robotic navigation, and augmented reality has been preliminarily integrated into preoperative planning and intraoperative navigation, which, together with novel biomaterials and internal brace augmentation, collectively improve graft healing quality. For meniscal and cartilage injuries, knotless all-inside suture devices, 3D-printed personalized scaffolds, and stem cell- and exosome-loaded biomaterials have driven the transition from repair techniques toward regenerative transformation. In joint arthroplasty, computer navigation and surgical robots significantly improve the accuracy of alignment and prosthesis positioning, but the early functional advantages have not yet translated into stable clinical benefits at mid- to long-term follow-up. Patient-specific instrumentation combined with 3D-printed bone models offers supplementary value in complex cases and residency training, while 3D preoperative planning enables the accessibility of precise surgery at a lower cost. Artificial intelligence (AI)-assisted techniques have been applied to the entire perioperative workflow, ranging from preoperative 3D planning and prosthesis size prediction through intraoperative autonomous strategy learning by robots and real-time soft tissue balance perception, to postoperative risk prediction and wearable device-based rehabilitation monitoring, initially establishing a data-driven intelligent decision-making system. Currently, the field still faces challenges such as insufficient long-term follow-up evidence, high technical costs, limited grassroots promotion, and limited generalization ability of AI models. In the future, it is necessary to establish diagnosis and treatment guidelines and databases tailored to the characteristics of the Chinese population based on multicenter studies, promote technical integration and cost optimization, and realize the effective transformation from precise techniques to accessible clinical applications.