四合-骨融合术在儿童先天性胫骨假关节联合手术中的应用

Application of ＂4-in-1 osteosynthesis＂ in the combined surgical technique for the treatment of congenital pseudarthrosisof tibia in children

目的探讨儿童先天性胫骨假关节联合手术同时行四合一骨融合术的近期疗效。方法2012年5月至2014年9月采用联合手术十四合-骨融合术治疗先天性胫骨假关节患儿12例，男10例，女2例；年龄1．2-10．1岁，平均4．4岁，3岁以下者5例。左侧4例，右侧8例。5例既往有1~4次胫骨假关节手术史。均伴腓骨假关节，胫腓骨假关节位于同一水平。2例伴胫骨近端发育不良，7例伴I型神经纤维瘤病。10例患儿胫骨短缩2-11cm，平均4．5cm。联合手术包括经足踝髓内固定、Ilizarov外固定架固定和包裹式自体髂骨植骨；同时行四合-骨融合术，在植骨前将胫、腓骨四个骨端缝合，使胫腓骨假关节融合。随访时评估早期愈合率及再骨折发生率，并观察踝外翻、胫骨近端外翻和胫骨不等长等后遗畸形情况。结果术中7例行胫骨延长。手术时间3．5-4．5h，平均4h；出血量60-150ml，平均113ml。所有病例均获得随访，随访时间14．3-45．7个月，平均28．5个月。均达到早期愈合，愈合时间3．3~4．8个月，平均4．1个月。随访期间7例（58％，7／12）存在胫骨不等长，双侧胫骨差0．8~5．0cm，平均2．9cm，其中4例行胫骨延长术。2例（17％，2／12）发生胫骨近端外翻，分别为13°和15°。术后胫骨假关节愈合区域的横截面积增大至胫骨远、近端骨干横截面积平均值的1．5-2．8倍，平均2．3倍。随访期间均未发生再骨折及踝外翻。8例患儿恢复踝关节活动，背伸20°-30°，平均23。；跖屈40°-50°，平均42°。另4例踝关节仍固定于中立位。结论在联合手术同时行四合一骨融合术治疗伴腓骨假关节的儿童先天性胫骨假关节近期疗效良好。胫骨假关节愈合处横截面积增加，早期愈合率高，但存在胫骨不等长、胫骨近端外翻畸形等并发症。

Objective To investigate the indications, operative technique, and outcomes of combined surgical technique and ＂4-in-1 osteosynthesis＂ for congenital pseudarthrosis of the tibia （CPT）. Methods A retrospective study was performed on 12 patients （10 boys and 2 girls） with CPT and fibular pseudarthrosis who were treated with combined surgical technique and ＂4-in-1 osteosynthesis＂ from May 2012 to September 2014. The average age during surgery was 4.4 years （1.2-10.1 years）. Five patients were under the age of 3 years old. Seven patients had no previous surgery, but 5 patients underwent between one and four unsuc- cessful procedures in other hospital. Of the 12 patients, two had proximal tibia dysplasia, seven cases exhibited neurofibromatosis type I . 10 cases showed limb length discrepancy （LLD） with an average limb length of 4.5 cm （2-11 cm）. Combined surgical tech- nique and ＂4-in-1 osteosynthesis＂ included intramedullary rod insertion, installation of Ilizarov^s fixator, tibio-fibular cross union, and wrapping autogenic iliac bone graft. Seven patients were planned by proximal tibial lengthening. The incidence of refracture, ankle valgus, tibial valgus and LLD in patients were investigated with an average follow-up time of 28.5 months （14.3-45.7 months）. Results Seven patients were treat by tibia lengthen at the same time. The average operating time was 4 h （3.5-4.5 h）; the average blood loss was 113 ml （60 -150 ml）. All patients achieved primary union, and the average primary union time was 4.1 months （3.3-4.8 months）. Seven （58%） cases showed LLD with an average limb length of 2.9 cm （0.8-5.0 cm）, four patients were treat by tibia lengthen. Two （17%） cases exhibited tibial valgus; one case with the tibial valgus deformity of 13°; one case with the tibial valgus deformity of 15°. The cross sectional area of bone graft was enlarged to 2.3 times （1.5-2.8 times） of the tibia shaft. No case showed refracture and ankle valgus during the follow-up periods. Eight cases restored movement of ankle joint with an aver- age dorsiflexion 23° （20°-30°） and an average plantar flexion 42° （40°-50°）, and the function of ankle joint was normal. The ankle joint in other 4 cases were fixed in neutral position. Conclusion Combined surgical technique and ＂4-in-1 osteosynthesis＂ canprovide satisfactory results in short-term follow-up in treating CPT. By the help of this procedure, the early healing rate is high with larger cross-sectional area in fusion joint. However, some complications, such as tibial valgus and unequal leg length, should be considered.