Application of elastic intramedullary nailing in the treatment of radial neck fractures in children Zhang Yapeng Li Yang Zhou Zhilin Sun Jun1 Sun Jun, Department of Pediatric Orthopedics, Anhui Children’s Hospital, Anhui Province, China [Abstract] Objective To explore the application of elastic intramedullary nailing technique in the treatment of radial neck fractures in children. Methods Sixteen cases of radial neck fractures in children were treated with elastic intramedullary nailing internal fixation from January 2008 to April 2010. Results All 16 cases were followed up for 4 to 18 months, and healing was good. Conclusion The treatment of radial neck fractures in children with internal fixation of elastic intramedullary nail has the characteristics of reliable efficacy, minimally invasive, early return to functional activity, and few complications. 【Key words】 Children; radial neck fracture; elastic intramedullary nail; minimally invasiveElastic nails radial neck fractures in the children’s applicationZhangYaPeng LiYang ZhouZhiLin,et al. Department of Department of Pediatric Orthopaedics, Anhui Provincial Children’s Hospital, Hefei 230051,China 【 abstract 】 Objective: to explore the elastic nails Methods: from January 2008 in April 2010 with elastic nails internal fixation for children 16 cases radial neck fractures Results : 16 cases have been followed up, follow-up time 4 ~ 18 months, healing all good. Conclusion ：elastic nails internal fixation for children with radial neck fracture, reliable, and minimally invasive effect early recovery function activities, the characteristics of less complications. Key words 】 children; The radial neck fracture; Elastic nails; Minimally invasive Author Affiliation：Anhui Provincial Children’s Hospital, Department of Orthopedics. 1 is the corresponding author. Fractures of the radial neck in children are often seen in clinical practice, with radiographs showing a fracture or a “crooked cap” of the epiphysis. For fractures with II and III degrees of displacement (>30 degrees) of O′brien’s type [1], it is difficult to achieve good repositioning with traditional revision methods, while surgical treatment has many complications, difficult internal fixation, and easy re-displacement. From January 2008 to January 2010, 16 cases of radial neck fractures in children were treated by flexible intramedullary nailing with satisfactory results, which are reported below. 1 Clinical data 1.1 General data The 16 cases in this group were 8 males and 6 females; the youngest was 5 years old and the oldest was 16 years old. The youngest was 5 years old and the oldest was 16 years old. 10 cases were left-sided and 6 cases were right-sided. According to the O′brien typing, there were 9 cases of moderate and 7 cases of severe fractures. There was one combined ulnar fracture, one medial epicondyle fracture, and two radial nerve injuries. The surgery was performed under basic anesthesia with brachial plexus nerve block, and a longitudinal incision of about 2 cm in length was made 2 cm above the distal radial styloid process (dorsal radius of the distal radius). The patient was placed in the supine position, and a longitudinal incision was made about 2 cm above the distal radial styloid process (45° to the long axis of the radius), bluntly divided to the periosteum, the extensor tendon was distracted, the proximal end of the incision was perpendicular to the bone cortex, and the intramedullary nail was inserted. The intramedullary nail is mounted on the inserter, the elastic nail is introduced to the level of the fracture end, and partial or complete reduction of the fracture is accomplished by closed reduction under the monitoring of the C-arm machine, supplemented by prying and repositioning with a percutaneous kerf pin if necessary [2]. The intramedullary nail is continued to be inserted, making sure that the tip of the nail hooks the proximal end of the fracture and reaches the radial head under the cartilage as shown on the C-arm X-ray machine, and then the fracture is repositioned by rotating the intramedullary nail and checking the position of the tip of the nail in the proximal medullary cavity under the C-arm X-ray machine. Finally, the intramedullary nail was completed fixed by gently striking the propeller, the excess intramedullary nail was cut, and the incision was sutured. After the operation, the elbow was flexed at 70°~90° in neutral position with external fixation in a plaster brace. 1.3 Postoperative treatment: Antibiotics were routinely given to prevent infection, and the plaster cast was removed for functional training 3~5 weeks after surgery, and the internal fixation was removed after 3 months. 2 Results 2.1 Efficacy evaluation criteria The radial tuberosity was evaluated according to the Metaizeau evaluation criteria [3]. The criteria for rehabilitation were: a) good: anatomical repositioning; b) good: tilt less than 20°; c) fair: tilt 20°-40°; d) poor: tilt greater than 40°. Posterior efficacy criteria, a) good: no restriction of movement; b) better: restriction of flexion and extension or forearm rotation and post-rotation less than 20°; c) average: restriction of flexion and extension or forearm rotation and post-rotation 20° to 40°; d) poor: restriction of flexion and extension or forearm rotation and post-rotation greater than 40°. 2.2 Evaluation of efficacy The postoperative radiographs showed 11 good cases and 5 good cases in 16 cases in this group, all of which achieved anatomical repositioning or near-anatomical repositioning. None of the cases had incisional infection, and the fractures were clinically healed on postoperative radiographs 3 to 4 weeks after surgery. After 4 to 18 months of follow-up, there were 11 good cases and 5 good cases with no premature closure of the radial head epiphysis, ischemic necrosis or ulnar radial fusion, and no ectopic calcification foci around the joint. Typical cases are shown in the figure below. Figure Pre- and postoperative radiographs of a 9-year-old male child 3 Discussion In recent years, with the continuous improvement of new materials and technologies as well as the development of minimally invasive concept and minimally invasive techniques, more and more children’s fractures are treated by minimally invasive surgery, especially for unstable fractures of the extremities in children, intramedullary fixation has been widely accepted. The elastic stable intramedullary nail (ESIN) was first reported by Frenchman Jean Prevot in the late 1970s [4, 5], and the operator can pre-bend the intramedullary nail according to the fracture characteristics to achieve two or more points of fixation with fracture repositioning, while keeping the fracture end in longitudinal micro-motion to promote bone scab formation, so the elastic stable intramedullary nail is a minimally invasive procedure suitable for the treatment of children’s fractures. 3.1 The elastic intramedullary nail can be used for both reduction and fixation in the treatment of radial neck fractures in children. Radial neck fractures in children are intra-articular fractures of the elbow joint and require anatomic or near-anatomic repositioning as much as possible; otherwise, elbow flexion and extension and forearm rotation may be affected. For fractures with mild displacement of the radial neck fracture, the fracture is generally more stable by manipulation, but for fractures with radial head tilt greater than 60° or with elbow joint dislocation, the lateral edge of the radial neck often has different degrees of insertion and compression, and the joint capsule around the joint is torn and destroyed, and the lateral radial head loses the support of the original radial neck after repositioning, which is mostly unstable. At present, the clinical treatment mostly adopts percutaneous prying and repositioning external fixation, percutaneous prying and repositioning internal fixation, incision and repositioning external fixation or incision and repositioning internal fixation, etc. After surgery, the simple external fixation has the possibility of re-displacement, plus the operation of internal fixation with a kerfing needle is difficult, and it is easy to cause postoperative radial head ischemic necrosis. The tip of the intramedullary nail hooks the distal end of the fracture and plays the role of repositioning by rotation. The curved head of the elastic nail facilitates the insertion of the intramedullary nail and fixes the proximal end of the fracture at the same time to avoid re-displacement, which results in a higher success rate of closed fracture repositioning and more accurate efficacy. 3.2 Advantages of the elastic intramedullary nail in the treatment of radial neck fracture in children a) conforming to the minimally invasive technique, only a small incision is needed at the epiphysis, which is less traumatic, easy to operate and less scarring; b) the titanium elastic intramedullary nail can better control the axial displacement, translation and rotation of the fracture, so that the fracture is in a biologically stable state and has sufficient stability for early activities, and at the same time avoiding the complications of joint stiffness and muscle c) The flexible intramedullary nail is a flexible intramedullary nail, which can be threaded in the direction of the medullary cavity without using a medullary drill and destroying the endosteal blood supply, without cutting the periosteum and the hematoma at the fracture, avoiding damage to the blood supply of the fracture block and facilitating the natural healing of the fracture. In this group, the fracture of the radial neck was seen to pass through the bone scab 3-4 weeks after surgery, avoiding the poor prognosis of ischemic necrosis of the radial head and then resorption, which is common in the incision and repositioning method and unacceptable to both the doctor and the patient; d) the infection rate was reduced without incision to expose the fracture end; e) the internal fixation was simple to remove after the fracture healed, and it could be extracted only by incision under the skin, saving time and cost. 3.3 Intraoperative precautions a) The films should be carefully read before surgery to clarify the direction of displacement of the fracture and to make a good repositioning plan; b) The opening should avoid injuring the epiphyseal plate and affecting the normal development of bone; c) When repositioning the fracture and internal fixation of the intramedullary nail, a one-time success should be strived for, and if necessary, a prying repositioning is feasible to avoid repeated retraction, which can lead to hollowing of the proximal end of the fracture and unreliable fixation; d) The angle of the elastic nail can be properly adjusted intraoperatively. The angle of the tip of the nail, we generally make the original arc slightly reduced to facilitate intraoperative repositioning and fixation; e) the treatment of the tail of the nail: to stay outside the bone window about .5 cm is appropriate, not too long, in order to avoid the occurrence of pseudocysts, and sometimes also cause local skin irritation pain and infection. 【Reference】 ［1］Ji Shijun, Pan Shaochuan, Wang Jimeng, Editor-in-Chief, [Pediatric Orthopedics] Chapter 17 Section 10 Radial Neck Fracture 1992 ed. [2］ Original work by Lynn T. Staheli Pan Shaochuan, ed. [Practical pediatric orthopedics] Chapter 11 XXXVI Radial neck fracture reduction and fixation 2007 ed. [3］ Metaizeau JP, Lascombes P, Lemellel JL, et al. Reduction and fixation of displaced radial neck fractures by closed intramedullary pinning [J].J Pediatr Orthop, 1993, 13(3): 355360. [4] Prevot J, Lascombes P, Ligier JN.The ECMES ( Centro Medullary Elastic Stabilising Wiring) osteosynthesis method in limb fractures in children.Principle, application on the femur.Apropos of 250 fractures followed up since 1979 [J].Chirurgie, 1993, 119(9): 473476. [5] Huber RI, Keller HW, Huber PM, et al. Flexible intramedullary nailing as fracture treatment in children [J].J Pediatr Orthop, 1996, 16(5):602605.