Prospective review of open reduction and internal fixation with Kirschner wires (K-wires left exposed) fixation in displaced and rotated (Song V) lateral humerus condyle fractures in children

INTRODUCTION

Fractures of the lateral condyle of the humerus account for 10-15% of all elbow fractures in children.^1,2 These include Salter Harris type 2 and type 4 growth plate injuries in which the fracture crosses the distal humeral growth plate and enter the elbow joint.³ It is a fracture of necessity.

Open reduction and internal fixation with K-wire is treatment of choice for the displaced as well as minimally displaced lateral condyle fractures of children to prevent malunion, nonunion and further displacement.^4,5 We prospectively evaluated functional outcomes, complications, fracture union for displaced lateral condylar fractures of distal humerus (stage II, III, IV and V of Song et al classification) in children. Song Stage I fractures can be well managed with long arm cast. In case of stage II fractures, directly percutaneous K wires were applied for the fracture fixation without further manipulation. In stage III or IV fractures, longitudinal traction was applied in elbow joint with slight varus force while fracture fragment was compressed simultaneously in antero-medial direction with surgeon’s thumb. Once fracture fragment was reduced within 2 mm in all the views under fluoroscopy, a slight valgus force was applied on elbow joint with forearm supinated and elbow slightly extended to maintain the fracture in position. Usually two parallel K wires were applied from lateral side to fix the fracture. For the children upto 5 years of age, K-wire of 1.5 mm was used for fixation while those with more than 5 years K-wires of 1.8 mm was used. Nonunion is a common problem in fractures of the lateral humeral condyle.⁶ Fractures can be classified using the Milch classification: type I in which the fracture line traversed the ossific nucleus of the lateral condyle or type II where fractures exited through the trochlea.⁷

Fractures can also be classified according to the degree of displacement based on Stanley's classification, a modification of the classification developed by Jacob et al stage I displacement (CRACK) is one in which the injury is a stable fracture that can be treated with a cast alone (less than 2 mm displacement).⁸ Stage Il displacement (GAP) is a fracture with a significant lateral gap indicating the fragment has undergone some rotation and is unstable.

Stage Ill displacement (FLIP) is a fracture with complete rotation of the condylar fragment.

While internal fixation is usually achieved with K-wires in young children, compression screws can be used in older children.^9,10

Objective of study is to assess the outcomes of ORIF with K wires fixation of lateral epicondyle of humerus fractures (which are displaced and rotated) according to Hardacre criteria and also compare the incidence of complications. Postoperative range of motion were also noted.

METHODS

This was prospective analytical study conducted in Rajendra Institute of Medical Sciences, Ranchi from December 2020 to December 2022 which consisted of 30 patients (of whom only 27 were present for follow ups) who were treated by ORIF with K-wires fixation. Informed consent was taken from the parents of all patients.

Inclusion criteria

Patients with age younger than 14 years and presence of displaced and rotated lateral humeral condyle fracture treated by OR/IF and K- wires, and fracture less than 1-week old were included.

Exclusion criteria

Patients with undisplaced fractures, open fractures, other ipsilateral upper-limb fractures, pathological fractures, or fractures treated later than 14 days after injury were excluded.

A lateral approach to the distal humerus using the interval between the brachioradialis and the extensor carpi radialis longus anteriorly and the triceps posteriorly was performed under general anesthesia and tourniquet. Considering the blood supply to this area, minimal posterior dissection of the soft tissue from the distal fragment was used to reduce the risk of avascular necrosis of the capitellum. The joint surface was accurately reduced under direct vision and 2 convergent Kirschner wires were inserted. After wound closure, the elbow was supported in plaster backslab.

We followed the classification pattern given by song et al as shown in Table 1.

Classification pattern is more accurately described by additional internal oblique and external oblique views besides routine antero-posterior and lateral views of injured elbow joint. Displacement of fracture fragment was measured from the distal end of lateral metaphyseal cortex of distal humerus to lateral cortex of fractured fragment in AP, internal oblique and external oblique views. In lateral view posterior cortex was used to measure the displacement. Stage V fractures are difficult to managed by closed method alone and was better managed with open reduction and fixation. All the cases were performed under general anesthesia. Pre-op i.v. antibiotics was given, then patient was given 3-days oral antibiotic only. Posterior slab was applied at the time of fixation of fracture. At 3-4 weeks both posterior slab and K-wires were removed once the union was confirmed in check X-ray. Radiographic criteria for a healed fracture consisted of callus across the fracture site in antero-posterior and lateral radiographic views of the elbow. If callus formation was visible radiographically, K-wires were removed and active mobilization of the elbow without a cast was allowed. If the fracture did not show radiographic union at 3-weeks then K-wires were continued for another 3 weeks and removed by 6 weeks.^9,10

Degree of fracture displacement, elbow range of movement, radiographic changes, varus-valgus deformities, carrying angle and any other related complications were noted at each follow-up and results were evaluated according to the criteria given by the Hardacre et al.¹¹

Statistical tool

Excel software and Microsoft words were used to analyse the data. Percentage was calculated for qualitative data.

RESULTS

Initially 30 patients were included in our study however only 27 patients were available during the final follow-up. So total number of patients included in our study were only 27.

In our study, male constituted of 62.9% while female children were 37.1%. Male dominance is because they are more involved in outdoor activities. Also, left elbows were more commonly injured (55.55%) as compared to right (44.4%). Major culprit for injuries was fall from height (44.4%), followed by playing indoor games (25.9%). RTA and sports each constituted of (14.8%). Functional outcomes based on Hardacre criteria are excellent (85.1%), good in 11.1% cases and fair in 3.7% cases.

In our study we had 1 patient each for pin tract infection and pseudovarus deformity. We didn’t get any patient complaining of non-union, avascular necrosis of capitellum and cubitus varus or valgus deformity.

DISCUSSION

The necessity of reduction and stabilisation of displaced and/or rotated lateral condyle fractures has been well established in the literature.^12-14 There are some controversies in the surgical management of these patients. The first controversy is as to whether displaced and rotated lateral condyle fractures should be managed with ORIF or with CRIF.¹³ Advocates of close reduction hypothesise that ORIF might be unnecessary in many cases and that it might even lead to avascular necrosis as a result of extensive soft tissue dissection.¹³ Song et al prospectively looked at 63 patients with lateral condyle fractures of the humerus.¹ They attempted closed reduction internal fixation using K-wires in all of them, but in 13 cases ORIF was required. Their success rate for fixation was 73% with no cases of non-union or malunion. A second controversy exists as to when the K-wires should be removed. Thomas et al managed 104 cases of displaced lateral condyle fractures of the humerus with ORIF and K-wire fixation.¹⁵ They advocated that 3 weeks of K-wire stabilisation is sufficient for the fracture to heal and therefore removed all the wires and began elbow mobilisation. In the present study, we removed the K-wire only after radiological union was evident. In agreement to our suggestion is the recent paper by Song and Waters and they mentioned that displaced fractures should be stabilized until they are healed radiographically.¹³

In our study, all the K-wires were left exposed. It has been stipulated that leaving the wires exposed could increase the risk of infection with reported incidences varying from 1 to 28%.¹⁶ In this study we believed that leaving the wires exposed, carries the advantage of wire removal in the outpatient department instead of administrating any kind of anaesthesia to the patient. In agreement to our practice is the study by Das De et al which advocates for leaving the wires exposed following ORIF of a lateral condyle fracture.¹⁶ According to Choudhary et al buried wire group have shown better union rate than exposed group, wires could be removed under local anaesthesia thereby avoiding any major procedure and also the risk of infection is low making this a better option than the exposed cohort.¹⁷

In displaced fractures of the lateral humeral condylar physis, improper reduction can result in both cosmetic deformities and functional loss of motion. Hence, open reduction has become the standard treatment.^8,18,19 Maintenance of reduction by 2 K-wires is standard practise for most clinicians.^18,19

Numerous studies have reported that extended use of a plaster splint or cast was required after internal fixation with K-wires.^18,20 Foster et al reported that 6-8 weeks of elbow joint immobilization was required after open reduction with K-wire fixation.¹⁸ Lau-nay et al reported that patients required a long-arm cast or splint for 4-10 weeks after internal fixation with K-wires.²⁰ In our study, we used an upper-arm cast or splint for an average of 6 weeks after surgery. Although patients were encouraged to perform active ROM exercises before bone union, many reported elbow pain that prevented such exercises. Indeed, many patients were unable to perform active ROM exercises for several weeks after cast/splint removal.

According to Tomori et al the safety and effectiveness of fixation with TBW and buried K-wires after OR/IF for lateral condyle fracture is more.²¹ Fixation with only 2 K-wires may be inadequate for patients requiring early active ROM exercises, which help prevent elbow joint contracture. TBW with K-wires thus appears to be the optimal method for fixation of lateral humeral condyle fracture.

After pediatric humerus lateral humerus condyle fixation, complications such as lateral spur formation, nonunion, avascular necrosis of the capitellum, cessation of physis growth or excessive stimulation of physis can be observed.²²

Bony overgrowth (lateral spurring) over the lateral condyle is a distinct radiological finding commonly seen in children following a fracture of the lateral condyle of the humerus.²⁶

Pribaz et al found that the initial fracture displacement degree was related to the degree of the spur, which did not affect the range of motion of the elbow joint. In our study no lateral spurring we’re seen.²³

Gaur et al reported that in a study of 15 patients in which they performed open reduction and internal fixation, a more appropriate reduction was achieved with the Z-plasty they performed in the origin of the extensor communis muscle, and that these patients had almost complete union without AVN.²⁴ Here, in our study also no AVN were reported.

Cubitus varus angulation has been a documented complication of lateral condyle fractures but in this study no case was noted.^25-27

Growth disturbance can occur after a lateral humeral condyle fracture in the form of a partial lateral growth plate closure or partial closure of the centre of the physis. In the latter case, a persistent gap between the lateral condylar physis and the trochlea could lead to a sharp angle wedge deformity also known as “fishtail deformity”. Fishtail deformity can lead to cubitus varus and usually does not cause any functional problems or requires surgical intervention.¹² No fishtail deformity was noted in this study.

In a large-scale review in the literature, it was reported that nonunion is a rare complication in pediatric humeral LCFs and this rate is 1.4%. The absence of callus in the fracture fragment for 8 weeks can be considered nonunion. It has been reported that the most important risk factor for nonunion is type 3 fractures, and this complication has been overcome by fixing the fracture fragment with a threaded screw.¹⁸

Bloom et al proposed that 2 K-wires sent divergently at an angle of 60 degrees constitute the most effective method of fixation. In addition, in this biomechanical study, they reported loss of reduction in the fracture line because of the valgus test in fractures treated with 2 parallel K-wires.²⁸ Blasier declined the potential for reduction loss in the fracture line of parallel 2 K-wire application.²⁹ In our hospital, there is a tendency towards performing divergent two K-wires, at about 60 degrees to each other. However, in some cases 3 K-wires were also introduced.

Limitations

Limitation of study are small number of patients, a short follow-up period and a failure to measure inter-observer errors in radiographic interpretation or functional evaluation.

CONCLUSION

Our findings demonstrate that open reduction and internal fixation with 2 or 3 K-wires (which were left exposed) and immobilization with casting for 3-4 weeks is sufficient for most of displaced and rotated fractures of the lateral condyle of the humerus. However, radiological evaluation is still necessary because in some cases the fracture may not have united in this time period. In some cases, K- wires are left until 6-7 weeks. Physiotherapy is done after removing K-wires. Excessive stripping of soft tissue attachment from the fragment is avoided to prevent AVN of fragment. In most of the cases we used K-wires in divergent fashion.

On the basis of the good outcomes and no significant complications in cases of Song V fractures, we advocate for open reduction of these injuries as opposed to the proposed closed reduction by some studies.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: The study was approved by the Institutional Ethics Committee

REFERENCES

1. 1. Bast SC, Hoffer MM, Aval S. Nonoperative treatment for minimally and nondisplaced lateral humeral condyle fractures in children. J Pediatr Orthop. 1998;18(4):448-50.
2. 2. Fontanetta P, Mackenzie DA, Rosman M. Missed, maluniting, and malunited fractures of the lateral humeral condyle in children. J Trauma. 1978;18(5):329-35.
3. 3. Salter R, Harris W. Injuries Involving the Epiphyseal Plate. J Bone Joint Surg (Am). 2001;83:1753.
4. 4. Song KS, Kang CH, Min BW, Bae KC, Cho CH, Lee JH. Closed Reduction and Internal Fixation of Displaced Unstable Lateral Condylar Fractures of the Humerus in Children. J Bone Joint Surg Am. 2008;90:2673-81.
5. 5. Song KS, Shin YW, Wug C. Closed reduction and internal fixation of completely displaced and rotated lateral condyle fractures of the humerus in children. J Orthop Trauma. 2010;24:434-9.
6. 6. Cardona JI, Riddle E, Kumar SI. Displaced fractures of the lateral humeral condyle: criteria for implant removal. J Pediat Orthop. 2002;22(2):194-7.
7. 7. Milch H. Fractures and Fracture Dislocations of the Humeral Condyles. J Trauma. 1964;4:592-607.
8. 8. Jakob R. Fowles JV, Rang M, Kassab MT. Observations concerning fractures of the lateral humeral condyle in children. J Bone Joint Surg Br. 1975;57(4):430-6.
9. 9. Loke W, Shuku MH. Yeap JK. Screw osteosynthesis of displaced lateral humeral condyle fractures in children: a mid-term review. Med J Malaysia. 2006;61:40-4.
10. 10. Li WC, Xi RJ. Comparison of Kirschner wires and A0 cannulated screw internal fixation for displaced lateral humeral condyle fracture in children. Int Orthop. 2012;36(6):1261-6.
11. 11. Hardacre JA, Nahigian SH, Froimson AI, Brown JE. Fractures of the lateral condyle of the humerus in children. J Bone Joint Surg [Am]. 1971;53:1083-95.
12. 12. Rockwood CA, Wilkins KE, Beaty JH, Kasser JR. Rock- wood and Wilkins’ fractures in children, 6th edition. Lippincott Williams & Wilkins, Philadelphia. 2006;1200.
13. 13. Song KS, Waters PM. Lateral condylar humerus fractures: which ones should we fix? J Pediatr Orthop. 2012;32(Suppl 1):S5-9.
14. 14. Thomas DP, Howard AW, Cole WG, Hedden DM. Three weeks of Kirschner wire fixation for displaced lateral condylar fractures of the humerus in children. J Pediatr Orthop. 2001;21(5):565-9.
15. 15. Thomas DP, Howard AW, Cole WG, Hedden DM. Three weeks of Kirschner wire fixation for displaced lateral condylar fractures of the humerus in children. J Pediatr Orthop. 2001;21(5):565-9.
16. 16. Das De S, Bae DS, Waters PM (2012) Displaced humeral lateral condyle fractures in children: should we bury the pins? J Pediatr Orthop. 2012;32(6):573-8.
17. 17. Choudhary N, Gupta S, Mahajan N, Mahajan R, Saharan A. Paediatric lateral humeral condyle fractures managed by kwire fixation, should the wires be buried or left exposed: a dilemma. Int J Res Orthop. 2021;7:78-81.
18. 18. Foster DE, Sullivan JA, Gross RH. Lateral humeral condylar fractures in children. J Pediatr Orthop. 1985;5(1):16-22.
19. 19. Rutherford A. Fractures of the lateral humeral condyle in children. J Bone Joint Surg Am. 1985;67(6):851-6.
20. 20. Launay F, Leet AI, Jacopin S, Jouve JL, Bollini G, Sponseller PD. Lateral humeral condyle fractures in children: a comparison of two approaches to treatment. J Pediatr Orthop. 2004;24:385-91.
21. 21. Tomori Y, Nanno M, Takai S. Kirschner Wire Fixation with and without Tension Band Wiring for Treatment of Fracture of the Lateral Humeral Condyle in Children. J Nippon Med Sch. 2020;87:17-23.
22. 22. Canale ST. Fractures and Dislocations in Children. In: Canale ST. Beaty JH editors Campell's operative orthopedics. Mosby Elsevier. 2008;1531-725.
23. 23. Pribaz JR. Beruthal NM, Wong TC, Silva M. Lateral spurring (overgrowth) after pediatric lateral condyle fractures. Pediatr Orthop. 2012;32(5):456-60.
24. 24. Gaur SC. Varna AN. Swarup A. A new surgical technique or old ununited lateral condvle factures of the humerus n children. J Trauma. 1993;31(1):68-9.
25. 25. So YC, Fang D, Leong JC, Bong SC. Varus deformity following lateral humeral condylar fractures in children. J Pediatr Orthop. 1985;5(5):569-72.
26. 26. Skak SV, Olsen SD, Smaabrekke A. Deformity after fracture of the lateral humeral condyle in children. J Pediatr Orthop B. 2001;10(2):142-52.
27. 27. Weiss JM, Graves S, Yang S, Mendelsohn E, Kay RM, Skaggs DL. A new classification system predictive of complica- tions in surgically treated pediatric humeral lateral condyle fractures. J Pediatr Orthop. 2009;29(6):602-5.
28. 28. Bloom T, Chen LY, Sabbarwal S. Biomechanical analysis of lateral humeral condyle fracture pining. J Pediatr Orthop. 2011;31(2):130-7.
29. 29. Blasier RD. Operative treatment of lateral condyle fractures. In: Tolo VT, Skaggs DL, editors. Master Techniques in Orthopedic Surgery Pediatrics. Philadelphia, PA: Lippincott Williams & Wilkeus. 2008;2.