Application Of Distraction Osteogenesis Technique In The Treatment Of Bone Tumor In Children's Limbs(Attachment:Treatment Of Two Cases Children's Limb-length Discrepancies Caused By Ollier's Disease With The Limb Lengthening)

Background: Children's limbs and bones at the stage of growth are common parts of benign and malignant bone tumors.When bone tumors invade one side of the epiphyseal plate,affecting the growth of the limbs,it can cause limb shortening,angular deformity and dysfunction.How to reconstruct limb function at the same time as the tumor resection is the key to clinical treatment.With the development of radiotherapy,chemotherapy,and surgical techniques,limb salvage for malignant bone tumors of the extremities has become preferred treatment.However,how to reconstruct limb function after malignant bone tumor resection has always been a challenge faced by orthopedist.Distraction osteogenesis technique,as one of the important findings in the field of orthopaedics in the 20 th century,has played an important role in the reconstruction of limb function in the treatment of benign and malignant bone tumors of the limbs.Limb lengthening technology compensates for the lack of long-term maintenance of reconstruction of limb function,such as artificial prosthesis replacement,massive bone allograft and other reconstruction methods,and it is a good choice for the treatment of children with bone tumors of the limbs.Ollier's disease is a rare of multiple endogenous chondromatosis involving unilateral involvement,often leading to abnormal limbs in children.In recent years,with the continuous deepening of research on Ollier's disease,the understanding of the disease has become more comprehensive,and new treatment methods have also been tried.In recent years,our department has applied limb lengthening technology to treat 2 cases of children with limb shortening caused by Ollier's disease and achieved satisfactory clinical results.Objective: To analyse the clinical effects and technical characteristics of surgical limb lengthening in the treatment of limb shortening caused by Ollier's disease in children,and to summarize the application experience of bone protraction technique in the treatment of bone tumors of children's limbs.Methods: 2 cases of children's limbs shortening caused by Olier's disease collected from June 2011 to June 2017,through the application of limb lenthening technique for correction,the humerus of the upper limb shortened child was extended by 8.5cm using Wagner external fixator,and the femur of the lower limb shortened child was extended by 9cm using Orthofix external fixator and the 26° varus deformity was corrected.The treatment experience was summarized.Postoperative follow-up was performed to evaluate whether there was recurrence,malignancy and limb function in the patients.The final follow-up was based on the Enneking limb functional scoring system for patients with limb bone tumors.Results: Both cases of children were followed up,among which the upper limb shortened child was followed up for 5 years,the child with shortened lower limb was followed up for 2 years.The results showed that both limb function and appearance were significantly improved,with no serious complications.A year post surgery,according to Enneking limb function scoring system,the upper limb shortened child got 97%,the child with shortened lower limb got 80%,satisfactory clinical results.Conclusions: Limb lengthening technique is an effective method for the treatment of children's limb-length discrepancies caused by Ollier's disease.It has a good therapeutic effect in clinical practice and has a very good application prospect.When using distraction osteogenesis technique to treat limb shortenings or bone defects in children with bone tumors in the limbs,the relevant treatment parameters,while referring to the classic Ilizarov technique,should emphasize the choice of treatment timing and how to comply with children's natural growth.