髁突囊内骨折的临床特点和分类研究

目的：探讨髁突囊内骨折的临床特点,并提出一种能全面反映囊内骨折的分型,为临床制定治疗计划提供依据。方法：统计上海交通大学医学院附属第九人民医院口腔颌面外科关节组自1999—2008年住院手术和2007年6月—2008年12月门诊非手术治疗,经全景片和CT确诊为髁突囊内骨折的连续病例242例329侧,进行临床特点分析。部分病例经MRI检查观察关节盘移位情况。根据CT冠状位重建对囊内骨折进行分类,根据骨折线的位置,将髁突囊内骨折分为4型。A型骨折的骨折线位于髁突外1/3,B型骨折的骨折线位于中1/3,C型骨折的骨折线位于内1/3,M型骨折为粉碎性骨折。结果：囊内骨折占髁突骨折的66.8%,摔伤是主要的致伤原因。45%的囊内骨折合并下颌骨骨折。骨折侧下颌支残端外上方移位或脱位出关节窝的比例是8.8%,其中73%伴颏部或下颌体骨折。95%的囊内骨折伴关节盘前内侧移位。囊内骨折类型中,A型最多（155侧）,占47.8%;其次是B型（95侧）,占29.32%;M型（61侧）,占18.8%;C型最少（13侧）,占4%。结论：囊内骨折是下颌骨髁突骨折的最常见类型,易合并下颌骨骨折,导致下颌支残端移位或脱出关节窝。以冠状CT为主要依据的分类方法,能较全面地反映髁突囊内骨折的类型。

Study of the clinical character and classification of intracapsular condyle fracture

PURPOSE： To study the clinical character and classification of intracapsular condylar fracture （ICF） of the mandible.METHODS： From 1999 to 2008,242 patients with 329 ICFs diagnosed by panoramic and CT scan in the TMJ division of Ninth People’s Hospital Shanghai Jiao Tong University School of Medicine were studied for the clinical character.Some patients had MRI to check the position of TMJ disc.According to the location of the fracture line,the ICF was divided into 4 types.In type A,the fracture line was located in the lateral third of the condylar head with the reduction of the ramus height.In type B,the fracture line was located in the middle third of the condylar head.In type C,the fracture line is located in the inner third of the condylar head.Type M is comminuted fracture of the condylar head.There was no ramus height reduction in Type B and C fractures.RESULTS： ICF accounted for 66.8% of all condylar fractures.Fall was the main cause of injury.Fifty-five percentage of ICFs accompanied mandibular fracture.Nine percentage mandibular ramus stumps displaced or dislocated out of the TMJ fossa,among which 73% had mandibular fractures.There were 95% ICFs which had TMJ discs displaced antero-medially with the fracture segment.Type A fracture was the most common type of ICF,which accounted for 47.8% （155 joints）;followed by Type B fracture,which accounted for 29.3% （95 joints）;and Type M fracture,18.8% （61 joints）;Type C fracture was the least type which accounted for 4% （13 joints）.CONCLUSION： ICF is the most common fracture type of mandibular condyle fracture.ICF is often combined with mandibular fractures which may cause the mandibular ramus stump displaced or dislocated out of the TMJ fossa.The new classification based on coronal CT scan can reflect the ICF type better.