摘要目的:探讨关节镜下盘复位术对青少年颞下颌关节（temporomandibular joint，TMJ）不可复性盘移位患者的髁突高度、关节盘长度以及盘移位距离变化的影响。方法:纳入2015年9月至2018年11月就诊于上海交通大学医学院附属第九人民医院口腔外科关节专科并且MRI诊断为不可复性关节盘移位（disc displacement without reduction，DDwoR）的青少年患者，根据是否行关节镜下盘复位术分为手术组和非手术组，并依年龄段分为5个亚组（11~14、15~16、17~18、19~20、21~24岁组），在随访前后MRI图像上测量髁突高度、关节盘长度、盘移位距离，采用SPSS 21.0软件进行统计学分析。结果:共纳入DDwoR患者172例，手术组纳入126例（183侧），男性17例，女性109例，年龄（17.4±3.0）岁，平均随访时间8.4个月（2.7~22.0个月）；对照组纳入119例（175侧），男性20例，女性99例，年龄（17.1±3.1）岁，平均随访时间9.5个月（3.0~22.1个月）。手术组随访前后髁突高度变化量［（1.3±1.8）mm］显著大于对照组［（-0.6±1.5） mm］（ P<0.001），且各年龄段两组间髁突高度变化量差异均有统计学意义（ P<0.01）。手术组不同年龄段患者的髁突增长量差异有统计学意义（ P<0.01），其中11~14岁组的髁突高度增长量［（2.4±2.2） mm］显著大于 19~20岁组［（0.8±1.9） mm］（ P<0.05）及21~24岁组［（0.4±1.1） mm］（ P<0.01），17~18岁组［（1.6±1.7） mm］显著大于21~24岁组（ P<0.01）；对照组各年龄段组间差异均无统计学意义（ P>0.05）。随访期内，对照组盘移位距离显著增加（ P<0.05），而关节盘长度变化差异无统计学意义（ P>0.05）。 结论:青少年TMJ DDwoR可造成髁突高度降低，关节镜下盘复位术能促进髁突新骨再生，且生长发育期髁突高度增加显著。

abstractsObjective:To compare changes of condylar height, disc length and displaced distance in adolescent temporomandibular joint (TMJ) disc displacement with or without arthroscopic discopexy.Methods:From September 2015 to November 2018, adolescents with magnetic resonance image (MRI) comfirmed disc displacement without reduction (DDwoR) were recruited in operation group (OG) and control group (CG) and were classified into five subgroups according to age (11-14 years, 15-16 years, 17-18 years, 19-20 years and 21-24 years). Changes of condylar height, disc length and displaced distance were measured before and after follow-up MRI. Student′s t-test, Welch′s t-test, Mann-Whitney U test, Wilcoxon signed-rank test, One-way ANOVA and Kruskal-Wallis test were used; P-value less than 0.05 was considered statistically significant. Results:One hundred and seventy two patients were recruited in the present study. One hundred and twenty six cases patients (183 joints, 17 males, 109 females, mean age 17.4±3.0 years) were in OG and 119 patients (175 joints, 20 male, 99 females, mean age 17.1±3.1) in CG. The mean follow-up time were 8.4 (2.7-22.0) and 9.5 (3.0-22.1) months respectively. Average condylar height changes of OG were significantly greater than CG (1.3±1.8 mm vs -0.6±1.5 mm, P<0.001) and differences were also seen in each age group ( P<0.001). In terms of age variations, average increase of condylar height in OG were (2.4±2.2) mm, (1.3±1.7) mm, (1.6±1.7) mm, (0.8±1.9) mm, (0.4±1.1) mm respectively ( P<0.001), differences were observed between 11-14 years vs 19-20 years ( P<0.05), 11-14 years vs 21-24 years ( P<0.01) and 17-18 years vs 21-24 years ( P<0.01) subgroups; and average changes in CG were (-0.7±1.6) mm, (-0.4±1.6) mm, (-0.8±1.5) mm, (-0.3±1.4) mm and (-0.9±1.5) mm respectively ( P>0.05). After follow-up in CG, further displaced disc was observed ( P<0.05) while disc length remained unchanged ( P>0.05). Conclusions:DDwoR in adolescents resulted in decreased TMJ condylar height while arthroscopic discopexy restored growth potential and promoted condylar new bone formation which was most prominent during growth period.