Objective: To introduce a novel comprehensive classification for femoral intertrochanteric fractures, and to accommodate the clinical requirement for the world-wide outbreak of geriatric hip fractures and surgical operations.
Methods: On the basis of reviewing the history of classification of femoral intertrochanteric fractures and analyzing the advantages and disadvantages of AO/Orthopaedic Trauma Association (AO/OTA) classification in different periods, combined with the current situation of extensive preoperative CT scan and three-dimensional reconstruction and widespread use of intramedullary nail fixation in China, the "Elderly Hip Fracture" Research Group of the Reparative and Reconstructive Surgery Committee of the Chinese Rehabilitation Medical Association proposed a novel comprehensive classification for femoral intertrochanteric fractures, focusing on the structure of fracture stability reconstruction during internal fixation.
Results: The novel comprehensive classification of femoral intertrochanteric fractures incorporates multiple indicators of fracture classification, including the orientation of the fracture line, the degree of fracture fragmentation, the lesser trochanteric bone fragment and its distal extension length (>2 cm), the posterior coronal bone fragment and its anterior extension width (involving the lateral cortex of the head and neck implant entry point), transverse fracture of the lateral and anterior wall and its relationship with the implant entry point in the head and neck, and whether the cortex of the anteromedial inferior corner can be directly reduced to contact, etc. The femoral intertrochanteric fractures are divided into 4 types (type A1 is simple two-part fractures, type A2 is characterized by lesser trochanter fragment and posterior coronal fractures, type A3 is reverse obliquity and transverse fractures, type A4 is medial comminution which lacks anteromedial cortex transmission of compression force), each of which is subdivided into 4 subtypes and further subdivide into finer subgroups. In a review of 550 trochanteric hip fracture cases by three-dimensional CT, type A1 accounted for 20.0%, type A2 for 62.5%, type A3 for 15.5%, and type A4 for 2.0%, respectively. For subtypes, A2.2 is with a "banana-like" posterior coronal fragment, A2.4 is with distal cortex extension >2 cm of the lesser trochanter and anterior cortical expansion of the posterior coronal fragment to the entry portal of head-neck implants, A3.4 is a primary pantrochanteric fracture, and A4.4 is a concomitant ipsilateral segmental fracture of the neck and trochanter region.
Conclusion: The novel comprehensive classification of femoral intertrochanteric fractures can describe the morphological characteristics of fractures in more detail, include more rare and complex types, provide more personalized subtype selection, and adapt to the clinical needs of both fractures and surgeries.
目的: 介绍一种股骨转子间骨折新的综合分类法，以适应老龄化社会髋部骨折病例数量爆发和手术量剧增的临床需求。.
方法: 在回顾股骨转子间骨折分类历史，并深刻分析国际内固定研究协会/美国骨创伤协会（AO/OTA）不同时期分类版本优缺点的基础上，结合我国目前广泛开展术前CT扫描及三维重建和普遍使用头髓钉内固定治疗的现状，中国康复医学会修复重建外科专业委员会“老年髋部骨折”研究小组针对股骨转子间骨折提出了新的综合分类法，重点关注内固定手术中获得骨折稳定性重建的结构。.
结果: 该股骨转子间骨折新的综合分类法纳入了骨折分类的多重指标，包括骨折线走向、骨折碎裂程度、小转子骨块及其向下延伸长度（>2 cm）、后侧冠状面骨块及其向前扩展宽度（累及头颈内植物入钉点的外侧皮质）、外侧壁前壁横贯骨折及其与头颈内植物入钉点的关系、前内下角皮质能否直接砥住等。共将股骨转子间骨折分为4型（A1型为简单的二部分骨折，A2型为含有小转子骨块和后壁冠状面骨折，A3型为反斜、横断骨折，A4型为内侧壁粉碎、压力负荷传导结构缺失），每型又分为4个亚型，并可继续分为更细的亚组。根据550例股骨转子间骨折三维CT总结，A1型占20.0%、A2型占62.5%、A3型占15.5%、A4型占2.0%。在亚型上，A2.2是后壁“香蕉样”骨块；A2.4是后壁骨折向小转子下延伸超过2 cm、向前在外侧皮质扩展至头颈内植物的入钉通道；A3.4是原发性全转子区骨折；A4.4是同时累及同侧股骨颈与转子间的节段性股骨颈骨折。.
结论: 股骨转子间骨折新的综合分类法能更细致地描绘骨折形态学特征，包含更多罕见和复杂类型，提供更多个性化亚型选择，适应骨折和手术数量双双增长的临床需求。.
Keywords: Fracture classification; anteromedial cortex; coronal fracture; femoral intertrochanteric fracture; three-dimensional reconstruction.