The Effect of Staged Surgical Treatment for Cubitus Valgus After Non-Union of Lateral Condylar Fracture of Distal Humerus in Older Children

Background: The purpose of this study was to investigate the effect of staged surgery (open reduction/internal �xation and osteotomy) for cubitus valgus after non-union of lateral condylar fractures of the distal humerus in older children. Methods: From January 2010 to January 2013, 9 patients were treated with two-staged surgery (open reduction/internal �xation and osteotomy). The study included 5 males and 4 females, with a mean age of 12.7 years. The minimum interval from fracture to the �rst surgery was 7 years and the maximum interval was 10 years (average 8.2 years). All patients had symptoms of injury of the ulnar nerve and instability of the elbow. The �rst surgery included internal reduction, internal �xation, and bone grafting, exposing the elbow through a Kocher lateral approach. The procedure included clearing the peripheric callus and proximal distal fracture end cicatrix with rongeur until cancellous bone was exposed, and �xation of the lateral condylar fragment with a hollow screw 4.0 mm in diameter and smooth Kirschner wire. The limb was immobilized in a long arm cast with the elbow at 90 degrees of �exion and the forearm in neutral rotation for 3 weeks, and active exercises were begun after removal. The internal �xation hardware was removed after 3 months. The second surgery, osteotomy of the supracondylar humerus, was completed after 6 months to correct cubitus valgus. Internal �xation from the osteotomy was removed 6 months later. Results: Six months after the second surgery, follow-up revealed that in all patients the lateral condylar fractures attained clinical union and cubitus valgus was corrected. Elbow function recovered well without arthrochalasis or humeral condylar avascular necrosis. All patients’ ulnar nerve injury symptoms disappeared. Conclusion: Staged surgery to treat cubitus valgus secondary to lateral condylar fracture non-union in older children serves to �rst provide elbow stability, then to correct cubitus valgus. Staged treatment may make up for the de�ciencies of conventional treatment. However, due to our relatively short follow-up time, the long term effects are unknown.


Background
Humeral lateral condylar fracture is a common elbow injury in young children; 16.9% of distal humerus fractures in children ages 2 to 8 are lateral condylar fractures. 1Due to epiphyses in children, standard xray examination of the lateral elbow does not fully reveal metaphyseal fractures.Therefore, clinicians are unable to fully assess the degree of fracture displacement, leading to possible neglect and misdiagnosis of fractures.If a lateral condylar fracture is missed, complications can occur, leading to di cult treatment later.Cubitus valgus deformity due to non-union occurs due to synovial uid leaking into the fracture site, inhibiting brin formation.This leads to a secondary callous formation.Additional factors include fracture fragments blocking the joint, continuity stretch of the forearm extensors, and the fragile blood supply of the lateral condylar.The treatment of humeral condylar old non-union fractures with elbow valgus deformity in older children has been controversial.The purpose of this study was to investigate the effect of staged surgery (open reduction/internal xation [ORIF] and osteotomy) in older children with humeral condylar old non-union elbow fractures with elbow valgus deformity, and to explore the surgical norms of this type of injury/deformity.

General Data
From January 2010 to January 2013, 9 older children (5 males and 4 females) between 11 and 14 years old (average 12.7) with humeral condylar fracture non-union old elbow valgus deformity were treated.Six were on the left side and three were on the right side.Intervals from fractures to the rst surgery ranged from 7 years to 10 years, with an average of 8.2 years.Seven cases had a carrying angle of 30°~ 40° and 2 had an angle of 40°~ 50°.All patients showed ulnar nerve symptoms.Four cases had functional limitations in the 4 th and 5 th ngers.All patients had a positive elbow side pull test and obvious elbow instability.

Operation method
The rst surgical stage was ORIF with bone grafting.A lateral longitudinal incision was completed, 1/3 of which was located over the joint and 2/3 proximal and distal to the joint.The triceps and brachioradialis were protected to ensure maintenance of the posterior soft tissue.The outer periphery of the callus was removed to clear distant off-side fascial scar hardened bone to expose the cancellous bone surface.Point reduction forceps were employed to reset the fracture involution, relying on the norm of proper involution elbow exion and extension function.Finally, 4.0 mm diameter hollow screws were xed and conventional implantation of allogeneic bone fracture was completed.Six months after ORIF, the second staged surgery (osteotomy) was carried out by using the outside of the original longitudinal incision, reconstruction locking plate xation, and smooth Kirschner wire (K-wire).Six months later, internal xation was removed.

Postoperative treatment
After the rst surgery, a long arm plaster cast was applied to ensure a 90° elbow exion and neutral position forearm.The cast was removed after 3 weeks.Three weeks after cast removal, functional activity training began.Another 3 months passed after the removal of internal xation.External xation with a cast was unnecessary after the second staged surgery, enabling the patient to begin elbow exion and extension exercises the second day of recovery.After four weeks, if the elbow was not fully recovered, patients were permitted to complete passive elbow exion and extension activities under the guidance of doctors.

Results
Our nine patients had an average of 18.3 months (12.5 to 26.0 months) of follow-up.Approximately three weeks after the rst surgery, x-ray examination showed that the original fracture line blurred.After 4 to 10 weeks (average of 6.8 weeks) all non-union fractures healed.After the second surgery, x-ray images of all patients revealed full healing at 5 to 10 weeks, with an average of 7.2 weeks.All patients regained a normal carrying angle of the injured limb, elbow function returned to preoperative status, ulnar nerve symptoms disappeared, and the elbow side pull test was negative.According to the Flynn norms, surgical treatment is considered a failure if elbow functional motion loss is more than 15°, carrying angle valgus angle exceeds 15°, or tie-up in the corner turns over for 5°.However, our clinical results showed that the effect of the staged surgical treatment discussed above was satisfactory (see Figure 1).

Discussion
condylar fracture is a common elbow injury, reaching 16.9% among distal humeral fractures in children ages 2 to 8 years old, with an average of 6 years old.In lateral condylar fractures with no shift or a displacement of less than 2 mm, long arm cast immobilization is effective. 13][4][5] Due to epiphysis, standard x-ray examination of the lateral elbow does not provide a full, clear view of metaphyseal fractures.Therefore, clinicians are unable to properly assess the degree of fracture displacement, leading to possible neglect and misdiagnosis of fractures.If a fracture is missed, the treatment becomes di cult and bony abnormalities can occur.Because the fracture surface slopes from the outside to the inside, elbow oblique plain lms can show the greatest degree of displacement.Accordingly, a standard x-ray of humeral condylar fractures should include front, side, and oblique views.
Flynn believes that a fracture of the humeral condylar is considered non-union if the patient has not recovered after 12 weeks of treatment. 2Non-union occurs when persistent synovial uid soaks the fracture site, resulting in inhibition of brin formation.This leads to secondary barrier callus formation.In addition, other factors contributing to non-union include the continuity stretches of the forearm extensors and the fragile blood supply for the lateral condylar. 3,4Humeral condylar fracture non-union in children can cause progressive elbow valgus deformity and skeletal dysplasia and is often accompanied by gradual emergence of chronic ulnar neuritis. 5Moreover, the fracture lines of lateral condylar fractures often extend to the trochlea, non-union of the fragment or bone absorption may shift the normal position of elbow joint, causing subluxation and instability of the elbow joint. 6In the case of a non-union, the lateral condylar in the elbow may still allow controlled motion and elbow function may not be impaired.However, in children, ulnar nerve palsy symptoms gradually appear as primary symptoms with lateral condylar fracture non-union. 7cording to reports, the surgery for humeral condylar fracture non-union combined with elbow valgus deformity has a high rate of complications due to the need for ORIF and autologous bone graft.Since the surgery requires the entire complex epicondyle of the humerus bone, an extensor cut is necessary in order to enhance the stability of the lateral condylar, increasing the risk of osteonecrosis of the external humeral condylar. 8,9,10,11,12,13In addition, if an abnormal lateral condylar is rigidly stabilized, loss of elbow function is likely to occur.A lateral condylar fracture results in an incomplete elbow pulley surface.
Overgrowth of the condylar causes the pulley surface to slope to the radial articular surface, leading to elbow dislocation and lateral elbow instability.Surgical treatment to restore the stability of the elbow without loss of elbow function is di cult.Toh et al. believes that long-term lateral condylar fracture nonunion only requires humeral osteotomy line and/or ulnar nerve release pre-surgery and does not immediately require directly addressing the non-union. 6However, Jakob et al. reported that simple elbow valgus deformity correction cannot completely solve ulnar nerve symptoms. 14Meanwhile, Dellon recommended initial ulnar nerve release surgery for traumatic ulnar neuritis.According to Dellon's literature review of over 50 articles reporting more than 2,000 patients, there was no statistical difference in the effect of various treatments for ulnar nerve compression. 15Abed et al treated nonunion of the lateral humeral condyle using a triple management ( xation of the nonunion site, dome corrective osteotomy, and anterior transposition of ulnar nerve) through a modi ed para-triceptal approach, the results showed that all patients gained union, all gained excellent or good elbow function according to the Mayo elbow performance score. 16However, there is still controversy about whether to treat the nonunion or not because of complications like stiffness of elbow and avascular necrosis of the fragment. 17 the past, the main treatment for lateral condylar fractures with non-union was osteotomy surgery to correct elbow valgus deformity. 18However, osteotomy surgery alone does not address instability of the elbow, and may result in detrimental impact on the patient quality of life.Conversely, the two staged surgery initially manages the stability of the elbow and then focuses on the deformity correction.As such, this approach addresses the de ciencies of conventional treatment modalities.Among our group of patients, the results were satisfactory and largely dependent on the success of the rst stage of surgery.
The following are key issues in the staged surgical approach: 1) The goal of surgical treatment is to restore the stability of the elbow without losing function.Our experience is that when reducing the distal fragment, shifting the fragment slightly forward will decrease the obstruction of the lateral condylar fragment to the radial head, thus providing the greatest degree of elbow function correction.
2) Hardened scars on the bone surface should be completely removed.
3) The blood supply of the lateral condyle of the humerus should be protected.Studies have shown that lateral condylar epiphyseal vascular supply goes through the posterior part of the articular surface of the condyle to reach the lateral condyle, while protection of the blood supply of the nonunited fragment is the key to successful management. 3,4,16 Terefore, the integrity of the soft tissue and vascular supply should be protected.

4)
In completing the secondary surgery to correct the valgus deformity in children, the posterior elbow approach should be avoided.The posterior approach requires splitting of the triceps bers and may impact the function of the elbow.We used the original lateral approach and on-line supracondylar osteotomies to safely manage the cubitus valgus and aesthetic needs.

Conclusions
According to the analysis of more than three years of clinical practice by the authors, staged surgery (ORIF and osteotomy) treatment of humeral condylar fracture non-union old elbow valgus deformity in our population of older children was effective to restore function and aesthetics.Our results suggest that this approach may be one of the best treatment choices for older children with elbow valgus deformity after humeral condylar fracture non-union.However, due to the limited number of cases in this group and short follow-up time, more studies with larger sample sizes and longer follow-ups are recommended.

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