半骨骺阻滞术治疗儿童先天性胫骨假关节愈合后胫骨近端外翻的疗效评价

Evaluations of hemiepiphysiodesis for proximal tibial valgus after initial union of congenital pseudarthrosis of the tibia in children

目的评价8字钢板半骨骺阻滞术治疗儿童先天性胫骨假关节愈合后胫骨近端外翻的临床疗效。方法回顾性分析湖南省儿童医院骨科2012年9月至2018年5月采用8字钢板半骨骺阻滞术治疗的儿童先天性胫骨假关节愈合后胫骨近端外翻患儿临床资料,患儿胫骨假关节手术后均获得一期愈合。收集手术前、取内固定时及末次随访时双下肢全长X线片及胫腓骨X线片,统计分析股骨胫骨角(mechanical tibiofemoral angle,mTFA)、股骨远端外侧角(anatomic lateral distal femoral angle,aLDFA)、胫骨近端内侧角(anatomical medial proximal tibial angle,aMPTA)及其变化,评估矫正效果及有无反弹。记录内固定留置时间、畸形矫正速率(°/月)。结果共18例(18侧下肢)患儿纳入研究,男女各9例;左侧10例,右侧8例。手术时年龄(4.2±1.4)岁。总随访时间(73.4±18.5)个月,其中内固定取出后随访时间(46.0±16.8)个月。患儿矫正效果均满意,平均矫正速率1.26°/月。1例术后发生切口脂肪液化,1例出现螺钉松动。无一例感染、内固定断裂、内固定失效、骺板损伤等并发症发生。术前mTFA(14.8±3.6)°、aLDFA(85.7±2.7)°、aMPTA(100.8±3.1)°;取内固定时mTFA(3.7±3.2)°、aLDFA(83.5±2.9)°、aMPTA(85.3±3.5)°;末次随访时mTFA(5.5±3.6)°、aLDFA(82.0±1.8)°、aMPTA(88.7±1.6)°。3个时间节点的mTFA、aLDFA、aMPTA差异均有统计学意义(P<0.01)。组间对比显示取内固定时和手术前mTFA的差异有统计学意义(P<0.01),取内固定时和末次随访时mTFA的差异无统计学意义(P>0.05);取内固定时和手术前aLDFA的差异有统计学意义(P<0.01),取内固定时和末次随访时aLDFA的差异无统计学意义(P>0.05);取内固定时和手术前、末次随访时的aMPTA差异有统计学意义(P<0.01)。取内固定时aMPTA恢复正常,但末次随访时aMPTA有增大趋势,其中4例出现反弹。结论采用8字钢板半骨骺阻滞术治疗儿童先天性胫骨假关节愈合后胫骨近端外翻畸形,矫正速率快,损伤小,矫形效果满意,但畸形有反弹的可能。

Objective To evaluate the clinical efficacy of hemiepiphysiodesis by eight-plate for proximal tibial valgus after congenital pseudarthrosis of the tibia(CPT)healing in children.Methods From September 2012 to May 2018,clinical data were retrospectively reviewed for 18 children(18 lower extremities)with proximal tibial valgus deformity after healing of CPT undergoing hemiepiphysiodesis by eight-plate.All cases had primary healing of CPT.By measuring the full-length radiographies of both lower extremities and tibiofibular films pre-operation,implants removal and the last follow-up,femoral tibial angle(mechanical tibiofemoral angle,mTFA),distal femoral lateral angle(anatomic lateral distal femoral angle,aLDFA)and proximal tibial medial angle(anatomical medial proximal tibial angle,aMPTA)were statistically analyzed for evaluating the correction outcomes and rebound phenomenon.Retention time of internal fixation was also recorded and rate of deformity correction(°/month)calculated.Results There were 9 boys and 9 girls.The involved side was left(n=10)and right(n=8).The average operative age was(4.2±1.4)years,the total average follow-up time(73.4±18.5)months and the average follow-up time after internal fixation removal(46.0±16.8)months.All cases had satisfactory outcomes with an average correction rate of 1.26°/month.There were fat liquefaction of incision(n=1)and screw loosening(n=1).No infection,breakage of internal fixation,internal fixation failure or epiphyseal injury occurred.Preoperative mTFA,aLDFA and aMPTA was(14.8±3.6)°,(85.7±2.7)°and(100.8±3.1)°respectively.During internal fixation removal,the above measurements were(3.7±3.2)°,(83.5±2.9)ånd(85.3±3.5)°.While in the last follow-up,mTFA was(5.5±3.6)°,aLDFA(82.0±1.8)ånd aMPTA(88.7±1.6)°.The differences in mTFA,aLDFA and aMPTA were significant at three timepoints(P<0.05).The inter-group comparison indicated that difference in mTFA was statistically significant during internal fixation removal and pre-operation(P<0.01).However no statistically significance existed in mTFA during internal fixation removal and at the last follow-up(P>0.05).Significant difference existed in aLDFA changes during internal fixation removal and pre-operation(P<0.01).However,no significant difference existed in aLDFA changes during internal fixation removal and at the last follow-up(P>0.05).Significant difference existed in aMPTA during internal fixation removal,pre-operation and at the final follow-up(P<0.01).aMPTA normalized after implant removal,but rose at the last follow-up.Four cases(22.2%)showed rebound phenomenon.Conclusion Hemiepiphysiodesis by eight-plate for proximal tibial valgus after initial union of CPT tibia in children offers the advantages of fast correction rate,minimal injury and satisfactory correction outcomes.However,there is a possibility of deformity rebound.