Cannulated Screw and Kirschner Fixation for the Treatment of Medial and Lateral Malleolar Epiphyseal Fractures in Children: A Retrospective Study of 36 Cases

SLR - January 2020 - Yen N. Tran

Reference: Jiang L, Wu J, Li M, Liu X, Luo C, Qu X. Cannulated Screw and Kirschner Fixation for the Treatment of Medial and Lateral Malleolar Epiphyseal Fractures in Children: A Retrospective Study of 36 Cases. J Orthop Surg Res. 2019 Aug 8; 14 (1): 254.

Scientific Literature Review

Reviewed By: Yen N. Tran, DPM
Residency Program: AMITA Health, St. Joseph Hospital – Chicago, IL

Podiatric Relevance: Malleolar epiphyseal fracture accounts for 11 percent of all epiphyseal fractures in children. Fractures of the distal tibial physis have among the highest rates of complications, including premature physeal arrest, bar formation, angular deformity, and articular incongruity. This retrospective study is the first to report on the use of Kirschner wire and cannulated screws for the fixation of lateral and medial malleolar epiphyseal fracture after closed reduction.

Methods: Ninety-eight cases with medial and lateral epiphyseal fractures were treated within a period of six years. Nondisplaced fracture were managed conservatively. Displaced fractures greater than 2 millimeters underwent closed reduction and percutaneous fixation (CRPF) as a first attempt. The medial malleolus epiphyseal fracture was fixated with one or two cannulated screws perpendicular to the fracture line and parallel to physis plate. The lateral malleolus epiphyseal fracture was fixated with axial implantation of smooth K wire. If CRPF failed to achieve anatomical alignment, then open reduction and internal fixation (ORIF) was performed. Thirty-six cases underwent CRPF, 62 cases were managed conservatively or ORIF and excluded from this review. There were 22 boys and 14 girls, ages between eight to 15. All medial malleolus fractures were Salter Harris type III, 11 lateral malleolar fractures were SH type I, and 25 lateral malleolar fractures were SH type II. Study outcomes were measured using the Baird-Jackson ankle score (max 100 points). The scores were divided into six categories: ankle pain 15, ankle stability 15, ability to walk 15, ability to run 15, ankle motion 15 and radiographic results 25. Scores from 96-100, 91-95, 81-90, and less than 80 were considered excellent, good, fair and poor.

Results: The average time to operation was 3.7 days. Twenty-three medial malleolar fractures were treated with one screw and 13 were treated with two cannulated screws. No cases of non-union or secondary displacement were observed. One complication of nerve numbness that self-resolved within 2 weeks post operative. Cannulated screws and K wires were extracted at average time of 2.8 months post operatively. The average Baird-Jackson ankle score was 94 (ranged 83-100). There were 13 excellent, 19 good, four fair and zero poor outcomes. The ankle recovered to pre-injury level of function on an average of 3.5 months. No premature physeal closure or ankle deformities were observed in any patients at the last follow up visit. The average follow up time was 25 months.

Conclusions: This retrospective study concluded that cannulated screw and K wire fixation is as a successful surgical option to treat medial and lateral malleolar epiphyseal fracture in children. This method shows a high rate of union, satisfactory functional outcomes and no complications. It is important to remember that selection of treatment for medial and lateral malleolar epiphyseal fracture should be tailored to the patient based on degree of fracture displacement, severity of accompanying local injury to soft tissue, and it is worth thinking about CRPF as a first attempt. Additional considerations were to perpendicularly cross the growth plate of the lateral malleolus preferentially with K wires and for SH III fractures screw fixation appeared to be a viable solution.