Classification and Bundle-Weaving Fixation for Posterior Cruciate Ligament Tibial Avulsion Fractures: Innovations and Applications of Key Techniques.

Abstract

Objective: Posterior cruciate ligament tibial avulsion fractures (PCLTAF) are characterized by complex injury mechanisms and treatment difficulties, with no standardized diagnostic or therapeutic guidelines currently available. This study aims to establish a classification-based Bundle-Weaving Zonal Fixation system to facilitate the precise treatment of PCLTAF.

Methods: A retrospective analysis was conducted on 100 patients with PCLTAF treated across multiple centers between 2016 and 2022. Based on fracture morphology, fragment characteristics, bone quality, and the extent of posterior ligamentous complex involvement, a novel classification system-Xu-Chen concise classification-was developed using an inductive approach, categorizing PCLTAF into nine subtypes. Guided by this classification, four bundle-weaving fixation techniques were designed, along with the development of a novel fixation system with tendon-weaving holes. One representative case from each subtype (n = 9) underwent open reduction and subtype-guided individualized fixation. Surgical time, intraoperative blood loss, complications, fracture healing, and functional outcomes (Lysholm and Tegner scores) were assessed.

Results: According to the Xu-Chen concise classification, nine patients (six males and three females; mean age, 45 years) underwent open reduction and individualized bundle-weaving fixation. The average surgical duration was 77.2 min (range, 60-95 min), and the average intraoperative blood loss was 23.3 mL (range, 15-40 mL). The mean follow-up period was 17.89 months (range, 12-22 months). The Lysholm knee score improved from 26.78 preoperatively to 97.22 postoperatively, while the Tegner activity score increased from 2.89 to 9.56. No complications such as deep vein thrombosis, joint stiffness, postoperative swelling, hematoma, infection, fixation failure, joint instability, or refracture were observed during follow-up. Only one elderly patient experienced superficial wound necrosis, which healed with conservative wound care.

Conclusion: The Xu-Chen concise classification and its corresponding tendon-bundled intraosseous fixation system offer a structured and standardized treatment pathway for PCLTAF. Preliminary results demonstrate promising outcomes in anatomical reduction, functional recovery, and surgical safety. This strategy shows clinical value in managing complex cases, such as comminuted fractures and osteoporotic bone.