MRI contribution in minimally displaced lateral humerus condylar fractures in children

Diagnosis and treatment of displaced humerus lateral condylar fracture is well codified with open reduction and pinning. For non-displaced or minimally displaced lateral condylar (NMDLC) fractures, diagnosis can be challenging because of cartilaginous structures none visualized on radiographs.

To determine the usefulness of MRI in evaluating articular extension of NMDLC fracture.

We reviewed consecutive NMDLC fractures during 6 years including children younger than 15 years old with displacement lesser than 2 mm (Rigault type I) at initial radiographs divided in two groups: only line fracture was viewed (R1a), displacement gap lesser than 2 mm (R1b). After elbow cast immobilization, children have got MRI. Surgery was performed in complete articular fractures. All children were seen after 1 mouth then at 6 month for elbow evaluation.

Thirty-one fracture, including twenty-two (70.97%) boys. Average age was 6.24 years (3 to 11). Fifteen fractures was classified R1a and sixteen R1b .According to MRI, seven fractures (22,6%) were metaphyseal Gp1, eleven (35,5%) were metaphyso-epiphyseal with an intact hinge cartilage Gp2 ,nine (29%) were complete Salter IV Gp3 and MRI reveals a supracondylar fractures in four cases. Fracture was metaphyseal more often in R1a group (40.0%) compared to R1b (6.3%). Gp3 group was significantly higher in R1b (50.0%) compared to R1a group (6.7%). For the sixteen R1b cases, eight presented articular cartilage involvement on MRI (Gp3) with concordant operative findings.

MRI is effective in assessing epiphyseal extension fracture providing accurate information for appropriate treatment.