三合一骨融合术在儿童先天性胫骨假关节联合手术中的应用

目的 探讨采取联合手术同时行三合一骨融合术治疗儿童腓骨完整型先天性胫骨假关节的短期疗效.方法 回顾性分析2014年3月至2015年8月采取联合手术(切除胫骨假关节及病变组织、经足踝髓内棒固定、伊氏架外固定装置加压固定)的同时,行三合一骨融合术(腓骨近端截骨、胫骨假关节远近二个骨端与局部完整的腓骨三者融合、取自体髂骨包裹式植骨)治疗17例腓骨完整型先天性胫骨假关节患儿的临床资料.17例均为单侧,术时平均年龄为3岁(1.1～7.7岁).其中,男12例,女5例;左侧7例,右侧10例.3岁以下者10例(占59％),2例既往有1次胫骨假关节手术史;均伴腓骨完整.伴有胫骨近端发育不良4例,1型神经纤维瘤病10例;11例患儿存在胫骨短缩,胫骨平均短缩1.6 cm (0.3～3.4 cm).术中行腓骨近端截骨、切除胫骨假关节及病变组织、经足踝髓内棒固定、伊氏架外固定装置加压固定、胫骨假关节二个骨端与腓骨融合、取自体髂骨包裹式植骨,2例同时行胫腓骨截骨延长.初步评价胫骨假关节患儿的早期愈合率,再骨折发生率,踝外翻、胫骨不等长和胫骨外翻等后遗畸形的发生情况.结果 本组平均手术时间4.1 h(3.3～4.2 h).所有患儿均获得完整随访,平均随访时间19.5个月(9～26个月).17例患儿均实现初期愈合,平均愈合时间4.9个月(4.1～7.8个月),初期愈合率为100％.13例(76％)患儿存在胫骨不等长,平均胫骨不等长1.2 cm(0.5～2 cm);6例(35％)患儿发生胫骨近端外翻,平均外翻7.8°(5～16°),均行胫骨近端内侧“8”字形钢板螺钉半侧骺板阻滞术予以矫正;2例患儿发生踝外翻,分别为12°、17°.术后胫骨假关节愈合区域的横断面积平均增大至胫骨远近端骨干处横断面积的1.74倍(1.14～2.60倍).17例患儿均未发生再骨折.5例患儿恢复踝关节活动,平均背伸22°(20～30°),平均跖屈41°(40～50°);另外12例踝关节仍固定于中立位.结论 在联合手术同时行三合一骨融合术治疗伴腓骨完整的先天性胫骨假关节初期愈合率高,胫骨假关节愈合处横断面积增加,短期疗效良好.

Application of 3-in-1 osteosynthesis in combined surgical technique for congenital pseudarthrosis of the tibia in children

Objective To explore the indications,operative technique and outcomes of combined surgical technique and 3 in 1 osteosynthesis for congenital pseudarthrosis of the tibia (CPT).Methods A retrospective study was performed on 17 children of Crawford type Ⅳ CPT with fibular intact undergoing combined surgical technique and 3 in 1 osteosynthesis from March 2014 to August 2015.There were 12 boys and 5 girls with an average operative age of 3 (1.1-7.7) years.Ten patients were aged under 3 years.Fifteen patients had no previous surgery,but two patients were unsuccessfully operated at another hospital.Among them,there were proximal tibia dysplasia (n =4) and neurofibromatosis type Ⅰ (n =1).Combined surgical technique and 3 in 1 osteosynthesis included proximal fibular osteotomy,excision of pseudarthrosis,intramedullary rod insertion,installation of ilizarov's fixator,tibi-fibular cross union and wrapping autogenic iliac bone graft.Two patients had proximal tibial lengthening.The incidence of refracture,ankle valgus,tibial valgus and limb length discrepancy (LLD) were tracked during an average follow-up period of 19.5 (9-26) months.Results Two patients underwent tibia lengthening simultaneously.The average operative duration was 4.1 (3.3-4.2) hours.All patients achieved primary union.The average primary union time was 4.9 (4.1-7.8) months.And 13 (76％) cases showed LLD with an average limb length of 1.2 (0.5-2.0) cm while 6 (35％) cases exhibited tibial valgus with an average tibial valgus deformity of 7.8° (5°-16°).Two cases had ankle valgus.One case had an ankle valgus deformity of 12° while another case 17°.The cross sectional area of bone graft was enlarged to 1.74 (1.14-2.60) times of tibia shaft.No refracture occurred during the follow-ups.Five cases had movement of ankle joint restored with an average dorsiflexion of 22°(20°-30°)and an average plantar flexion of 41°(40°-50°).And function of ankle joint was normal.Conclusions Combined surgical technique and 3 in 1 osteosynthesis are indicated primarily for bony union with a large cross-sectional area.The rate of early healing is high.It can provide satisfactory short-term outcomes for CPT.