The Analysis Of Risk Factors Of Cubitus Varus Deformity After Supracondylar Fracture Of Humerus In Children And The Choice Of Different Methods Of Reoperation

BackgroundSupracondylar fracture of the humerus(SCHF)is one of the most common elbow injuries in children,accounting for approximately 12-17%of all fractures in children.According to the damage mechanism,it can be divided into straight type and buckling type;The improved Gartland classification is the most common classification for describing straight type SCHF.At present,there is still controversy over the treatment of humeral supracondylar fractures,including indications for surgical treatment,timing of surgery,and selection of surgical methods.Closed reduction percutaneous Kirschner wire internal fixation(CRPP)is the primary choice for the treatment of significantly displaced SCHF.If the closed reduction fails or there is preoperative vascular and nerve injury or open fracture,open reduction percutaneous Kirschner wire internal fixation(ORPP)is required.The most commonly used internal fixation implantation method is cross Kirschner wire fixation.A large amount of literature has reported satisfactory treatment results,however,postoperative complications such as nail eye infection,vascular and nerve injury,cubitus varus deformity,internal fixation failure,and limited elbow joint movement are still common.Among them,cubitus varus deformity(CVD)is one of the most common late complications of deformity healing after SCHF surgery.However,there have been no large-scale research reports on the risk factors for CVD after SCHF CRPP/ORPP surgery.Although there is no significant limitation in elbow joint function in CVD patients,significant elbow deformities are the main reason why patients and their parents seek surgical treatment.A large amount of literature has reported various types of osteotomies,but each has its advantages and disadvantages.Modified stepped osteotomy(MRSO)is a new type of osteotomy that has received increasing attention in recent years.However,there is still no consensus on the optimal surgical plan.This study explores the following three aspects:1)Clarify the risk factors for CVD after SCHF CRPP/ORPP surgery,in order to provide reference for avoiding CVD after SCHF surgery;2)This study is the first to design and propose a new surgical method,namely the lateral elbow approach closed wedge osteotomy combined with distal centralization osteotomy(CDO),which can provide satisfactory three-dimensional correction and obtain satisfactory clinical and imaging results,while also minimizing the occurrence of lateral condylar protrusion after surgery;3)Analyze and compare the advantages and disadvantages of two MRSO and CDO osteotomy techniques,in order to provide reference for clinical practice.Part 1 Analysis of Risk Factors of Cubitus Varus Deformity after Operation for Humeral Supracondylar Fractures in ChildrenObjectives SCHF is one of the most common elbow fractures in children.Cubitus varus deformity(CVD)is one of the most common late-stage complications of deformity healing after SCHF surgery.However,there have been no study on the risk factors for CVD after SCHF CRPP/ORPP surgery.Method From January 2016 to December 2021,clinical and imaging data of all SCHF patients treated with CRPP/ORPP at Anhui Medical University Affiliated Provincial Children’s Hospital were collected and analyzed.Continuous variables were analyzed using t-test or ANOVA analysis.Categorical variables were used by Pearson χ2 tests or Fisher’s exact test;Use Logistic analysis were used to analyze the risk factors for CVD occurrence.P<0.05 indicates a statistically significant difference.Results A total of 3670 patients with SCHF met the inclusion and exclusion criteria and were followed up.According to Flynn’s criteria,the excellent and good rate is 94.77%;The average age of the patient at the time of surgery was 5.83(± 2.85)years old,with a median follow-up time of 12 months(6 to 65 months).Among them,there were 3593 cases of CRPP(97.90%)and 77 cases of ORPP(2.10%);The male incidence rate is mostly(1.56 times),and the left side is mostly(1.22 times);56.65%(2079 cases)of SCHF underwent emergency surgical treatment(≤12 hours).98.15%(3602 cases)were of straight type SCHF,of which 65.19%(2348 cases)were of Gartland Ⅲ type;The incidence of postoperative cubitus varus was 3.0%(110 cases).Statistical Research Finds Sidelines(χ2=4.281,P=0.039),flexion fracture(χ2=12.688,P<0.0001);Inverted angle on coronal plane(χ2=6.241,P=0.044),BA exceeds normal value by≥ 10°(χ2=14.932,P=0.001)is closely related to the occurrence of cubitus varus;Logistic regression analysis showed that flexion fractures,coronal varus angulation,and BA exceeding the normal range by ≥ 10° were independent risk factors for postoperative cubitus varus in children with supracondylar fractures of the humerus(OR=7.827、3.712、3.186,all P<0.05).Conclusion The vast majority of patients after SCHF surgery can achieve satisfactory results.There is a close correlation between flexion type SCHF and angulation of coronal plane inversion,which is equivalent to the occurrence of cubitus inversion.Part Ⅱ Correction of Pediatric Cubitus Varus by Centralization of the Distal Humeral Fragment:A Surgical Technique to Avoid Lateral Condylar ProminenceObjectives Cubitus varus is a well-recognized late complication of supracondylar humerus fractures in children.Various osteotomies have been described to correct this deformity,but each has disadvantages.The purpose of this study was to investigate the outcomes of a novel surgical technique,lateral closing wedge osteotomy combined with centralization of the distal humeral fragment(CDO),in cubitus varus.Meanwhile,the occurrence of post-operative lateral condylar prominence was observed.Methods From January 2015 to December 2019,thirty-six pediatric cubitus varus deformity patients who were treated with lateral closing wedge osteotomy combined with centralization of the distal fragment in our institution were included.The corrective osteotomies were performed via a standard lateral approach and fixed with crossed Kirschner wires.The pre-and post-operative full-length anteroposterior and lateral radiographs of bilateral upper limbs were assessed.At the same time,Clinical and radiological parameters were reviewed.Lateral condylar prominence index(LCPI)and any other complications were evaluated.Results The mean pre-operative humerus-elbow-wrist angle(HEWA)on the affected side was 20.9° of varus,which was significantly improved to 9.2° of valgus post-operatively.The mean post-operative value of LCPI was-0.047.Post-operative LCPI and HEWA was compared with the normal side,and there was no significant difference.All of the patients had excellent clinical and radiographic alignment.No surgical complications and limitation of range of motion were noted.No patient complained of the lateral bony prominence.Conclusion Lateral closing-wedge osteotomy by centralization of distal fragment is a safe and highly effective method,and prevent lateral prominence with a minimal complication rate.We recommend this technique for the treatment of cubitus varus in children.Part Ⅲ Clinical outcomes and Imaging Analysis of the Treatment of Cubitus Varus Deformity in Children using Centralization of the Distal Humeral FragmentObjectives Modified reverse step-cut osteotomy(MRSO)is a new surgical technique described recently for cubitus varus deformity correction.The CDO technology reported by our center can also achieve satisfactory results.The purpose of this study is to compare MRSO with CDO in term of clinical,radiological,and cosmetic outcomes in order to provide reference.Methods Between January 2015 and December 2021,sixty-four pediatric cubitus varus deformity patients were admitted to Anhui Medical University Affiliated Provincial Children’s Hospital.According to different osteotomy techniques,there were divided into two MRSO group(24 cases)and CDO group(40 cases).Clinical,radiological,and cosmetic appearance assessments were done at the final follow-up and compared between the two groups.Results All patients were followed up,with a median follow-up time of 31 months(24-61 months).The mean age of children in the MRSO and CDO groups is 9.9 years(3-16)and 8.6 years(3-16),respectively.The mean pre-operative HEWA in the deformed elbow of MRSO and CDO group was-20.9° and-20.7°,respectively,and the mean post operative HEWA in the corrected elbow of MRSO and RVO group was+10.8° and+10.3°,respectively.At the last follow-up after surgery,the LCPI of the affected side in the MRSO group and CDO group were 0.107 and 0.067,respectively.the change was statistically not significant when compared between the two groups(P=0.673).However,the operation time of CDO(P=0.000)and postoperative complication(P<0.0001)were significantly reduced compared to MRSO.There was no statistically significant difference(P>0.05)when the clinical,radiological,and cosmetic outcomes were compared between the groups at final follow-up.Conclusion CDO are comparable in terms of clinical,radiological,and cosmetic outcomes similar to MRSO;However,CDO has the advantage in term of shorter surgical time and fewer postoperative complications.We recommend CDO for the treatment of CVD.