He Dongmei, Cai Yihua, Yang Chi
Associate Professor, Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Key Laboratory of Stomatology, Shanghai, China.
Resident, Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Key Laboratory of Stomatology, Shanghai, China.
J Oral Maxillofac Surg. 2014 Apr;72(4):763.e1-9. doi: 10.1016/j.joms.2013.12.015. Epub 2013 Dec 27.
To analyze the main causes of temporomandibular joint (TMJ) ankylosis from condylar fracture in adults through a retrospective study.
The history and computed tomographic (CT) scans of patients diagnosed with ankylosis caused by mandibular condyle fracture treated in a closed fashion from 2010 to 2012 were reviewed in the department of oral surgery. According to the relation between the stump of the ramus and the TMJ fossa, condylar fractures were divided into 3 grades: grade 0, in which the ramus stump is in the fossa but without contact to it; grade 1, in which the stump of the ramus is in the fossa and attached to it; and grade 2, in which the stump of the ramus is laterally displaced out of the fossa. Other factors, such as type of condylar fracture, displacement of the fractured fragment, position of the disc, and the presence of concomitant mandibular fractures, also were analyzed for ankylosis development.
Of the 51 patients diagnosed with TMJ ankylosis, 13 patients (24 ankylosed joints) had full CT scans from injury to ankylosis, which showed that all condylar fractures were intracapsular fractures (ICFs), with sagittal fractures comprising 70%. Regarding the relation between the stump of the ramus and the TMJ fossa, no joints were classified as grade 0 (0%), 10 joints were classified as grade 1 (41.7%), and 14 joints were classified as grade 2 (58.3%). All discs were displaced with the fracture fragment, and the posterolateral retrodiscal tissue was torn. Among the condyle fractures leading to ankylosis, 77% featured symphysis fractures with widening of the mandibular arch.
The relation between the ramus stump and the TMJ fossa plays an important role in the prognosis of condylar fracture. Grade 0 is less likely to cause ankylosis; grade 1 is more likely to cause ankylosis and is the relative indication for surgery; and grade 2 is the strongest predictor of ankylosis and is the absolute indication for surgery. Other risk factors are sagittal ICFs and combined mandibular fractures with widening of the mandibular arch.
通过一项回顾性研究分析成人髁突骨折致颞下颌关节（TMJ）强直的主要原因。
对口腔外科2010年至2012年以闭合方式治疗的诊断为下颌髁突骨折所致强直患者的病史及计算机断层扫描（CT）进行回顾。根据下颌支残端与TMJ窝的关系，将髁突骨折分为3级：0级，下颌支残端位于窝内但未与其接触；1级，下颌支残端位于窝内并与之相连；2级，下颌支残端向外移位至窝外。还分析了其他因素，如髁突骨折类型、骨折块移位、盘状结构位置以及是否存在下颌骨合并骨折等与强直发生的关系。
在51例诊断为TMJ强直的患者中，13例患者（24个强直关节）有从受伤到强直的完整CT扫描，显示所有髁突骨折均为囊内骨折（ICF），其中矢状骨折占70%。关于下颌支残端与TMJ窝的关系，无关节为0级（0%），10个关节为1级（41.7%），14个关节为2级（58.3%）。所有盘状结构均随骨折块移位，后外侧盘后组织撕裂。在导致强直的髁突骨折中，77%伴有下颌骨联合骨折且下颌弓增宽。
下颌支残端与TMJ窝的关系对髁突骨折的预后起重要作用。0级较少引起强直；1级更易引起强直，是手术的相对指征；2级是强直的最强预测因素，是手术的绝对指征。其他危险因素包括矢状ICF以及下颌骨联合骨折伴下颌弓增宽。
