Functional Outcome of Titanium Elastic Nailing in Pediatric Tibial Fracture

Background: Tibial Diaphyseal fracture (TDF) is the third most common fracture seen in the pediatric population. Titanium elastic nailing (TEN) has been ideal for the management of tibial diaphyseal fractures to prevent complications. Therefore, this study aimed to access the functional outcome of TEN in pediatric Tibial diaphyseal fracture. Methods: This prospective cohort study was conducted on n=87 skeletally immature patients (6-12 years) at the two hospitals in Karachi from 1 st November 2019-30 th April 2021 including patients having unilateral, closed Tibial Diaphyseal fracture. The 75 patients (12 of them were lost follow-up) were analyzed in terms of wound infection, union, weight-bearing, limb shortening, rotation, angulation, and range of movement at knee and ankle joints. Paired t-test was used to compare the variables with a p -value < 0.05 was considered statistically significant. Results: Patients n=75 in this study had a mean age of 8.32±1.92 years with a mean weight of 25.8±6.9. The most frequent cause of injury was traffic accident 49(65.3%), followed by falling 19(25.3%) and 7(9.4%) with other causes. The most common fracture type was transverse 45(60%), followed by oblique 26(34.7%), and the remaining 4(5.3%) had a spiral fracture. All patients were allowed full weight-bearing at 9.8 ±1.5 week. At the end of this study, all patients regained knee and ankle range of motion ( p < 0.0001). Conclusion: Titanium elastic nailing was the ideal procedure for Tibial Diaphyseal fracture in the pediatric population, resulting in a short hospital stay, a rapid rehabilitation without complications.


INTRODUCTION
Pediatric tibial diaphyseal fracture (TDF) is the third most common fracture, contributing to 15% of all pediatric fractures 1,2 . Pediatric TDF, commonly found in young boys, are mostly oblique or transverse fractures of the middle and distal third of the shaft 2,3 . Thus, 70% of the fractures are isolated TDF, which are minimally displaced at presentation, while the remaining 30% are associated with Ipsilateral fibular fractures 4,5 . TDF in younger children is commonly caused due to minor falls and twisting injures. While in older children it is caused by sports-related trauma or motor vehicle accidents 5,6 .
Treatment is based upon a patient's age, concomitant injuries, and type of fracture 5 . Most TDF are treated with cast immobilization and closed reduction, however in cases where these methods do not provide an acceptable reduction in injures, surgical intervention such as external fixation and plate and screw fixation is used 7,10 . Over the last decade use of titanium elastic nailing (TEN) has been used to treat pediatric TDF to achieve optimum post-operative results with a low rate of complications [9][10][11] . TEN as compared to the external fixation offers minimal intrusion using small incisions and provides fewer chances of surgical trauma to the fracture site allowing early union and rehabilitation. External fixation is a heavyweight implant that might hinder the child's rehabilitation. Hence this method is not preferable in children [10][11][12] .
Intramedullary nailing can be of two types rigid or flexible. Although Rigid locked intramedullary nailing provides stable fixation, its use is avoided due to its tendency to damage proximal tibial physis. Hence elastic intramedullary nailing is preferable while treating TDF [11][12][13][14] . Closed reduction with percutaneous Kirschner wire fixation and cast immobilization is useful for unstable, oblique fractures in younger children 11,12 .
The main objective of this study was to assess the functional and radiological outcome of the TEN in the pediatric age group. Many studies have been conducted on this topic internationally however, in Pakistan not much data is available. Hence this study will be extremely helpful in discovering new treatment options for pediatric TDF. This study will not only give standard guidelines to surgeons regarding treatment but will also ensure the patients' mental and emotional wellbeing through quick and early mobilization and a complication-free treatment. During the TEN procedures, all patients were placed in a supine position under general anesthesia. Closed reduction was attempted after adequate reduction was achieved two nails with diameter 1/3 to that of the intramedullary canal were implanted through small incisions on lateral and medial sides of proximal tibia metaphysis. The nails were advanced beyond the fracture site bent slightly away from the bone to give stability. Before wound closure was performed, the accuracy of closed reduction was evaluated using the C-arm image intensifier intraoperatively. After three unsuccessful attempts at closed reduction, open reduction was performed with a small lateral incision followed by two Titanium elastic nails to stabilize the fracture.

METHODS
To maintain stability after the surgery, an above-knee cast was applied for six weeks. Follow-up visits were made at 2, 6, 12, 24 weeks, and then every 3 months for one year. On the 2 nd week follow up the Plaster of Paris back slab was removed, the wound was examined, the stitches were removed and the cast was reapplied for further four weeks. On the 6 th week follow up the cast was removed and partial weight-bearing was started. Physical therapy was started for initial gait training, more active exercises were started after the callus had reappeared. 6-8 months after the surgery, nails were removed when the fracture line was no longer visible radiologically.
At each postoperative follow-up visit, clinical and radiological assessments were done. The collected data will be entered into SPSS version 23. Quantitative variables, such as age, will be analyzed in terms of mean ± standard deviation. Qualitative variables such as gender will be documented in terms of frequency and percentage. Paired t-test was used to compare the variables with a p value < 0.05 was considered statistically significant.  (Figure 1, Table 1). The average time from accident to operation was 5±1 days. The mean hospitalization time was 3±1 days. In 75(100%) patients closed reduction was successful in the first attempt, while in the other 4 (5.4%) reduction was achieved in the second attempt. None of our patients were treated through open reduction. The fracture union time was 8.6 ± 2 weeks. The full weight-bearing time was 9.8 ± 1.5 weeks.  ) experienced nail irritation, which subsided without any treatment. There were 2 cases of limb shortening less than 2 cm. These cases come under satisfactory outcomes. There was no internal or external rotation found in any of the cases ( Figure  2). The anterior or posterior angulation found in 6 patients was below 10°, and medial and lateral rotations were less than 5° seen in 4 patients, which according to the protocol were good ( Table 2). The movements of knee and ankle joints were within normal limits except in 3 cases, where the range of knee motion was at 60% and after physiotherapy became 85% (p=< 0.0001, Table 3).

DISCUSSION
TDF is the third most common type of pediatric fracture. For decades, cast immobilization has been a standard method for TDF treatment 15,16 . The basic treatment principles of TDF are based upon the restoration of bone alignment, early mobilization, and rehabilitation after the union 17 . The invention of TEN made a revolution in the management of pediatric TDF. This is a biomechanically ideal method for weight-bearing long bone [18][19][20] . The current study showed excellent results, like studies conducted previously. The average time for fracture union is 8.6 ± 2 weeks. The full weight-bearing time was 9.8 ± 1.5 weeks. During the postoperative follow-up visit, there was no case of delayed, nonunion, or nail breakage. Knee and Ankle movements were satisfactory. There was no rotational deformity seen. This study shows good functional outcomes due to quick fracture union, rapid recovery, and rehabilitation.  22 . In our facility, we typically leave the TEN finishes on top of the skin because of the restricted delicate tissue support in the proximal tibia, which could clarify the event of the pin tract diseases in some of them and no different patients in comparative examinations 23 . Hence, a second intramedullary TEN with a fitting distance across was embedded through the proximal average of the tibia 24 . Following the assertion of fracture reduction and the placing of the TENs with C-arm 25 .

CONCLUSION
Titanium elastic nailing TEN is the treatment of choice for pediatric Tibial Diaphyseal fracture (TDF). It is a minimally invasive technique that ensures early and complete mobilization with a short hospitalization stay. This technique has a minimum complication rate and early rehabilitation which ensures a quicker return to school and their normal routine life is the third most common fracture seen in the pediatric population.

ACKNOWLEDGEMENT
We would like to acknowledge the hospital staff, OT technicians, nurses, and physiotherapists for their co-cooperation and contribution to this study.