Risk factors for the development of premature physeal closure after a McFarland fracture in children.

PURPOSE: In 1931, McFarland reported on medial malleolar physeal fractures and resulting deformities, which were later classified as Salter-Harris Type III and IV fractures of the medial malleolus. Ongoing controversy surrounding the factors that increase the risk for PPC in children with McFarland (MF) fracture.The retrospective study aimed to investigate the radiological and clinical outcomes of children treated surgically for MF fracture and evaluate the potential factors that increase the risk for premature physeal closure (PPC).

METHODS

We retrospectively reviewed 48 children who were surgically treated for MF fracture. Demographic data, including age at injury, gender, mechanism of injury, laterality, initial displacement, fracture type, time from injury to surgery, method of reduction, fixation method, time of hardware removal, and whether or not the patient developed PPC, were retrieved from the charts.

RESULTS

PPC occurred in 35.4% (17/48) of the patients. Our analysis revealed that patients with PPC were significantly younger than those without PPC (P < 0.001). Furthermore, our analysis revealed age and initial displacement as independent factors that increased the risk for PPC. Notably, age less than 11.5 years and initial displacement of more than 4.5 mm represented the cut-off points for an increased incidence of PPC. Overall, 11 out of 48 patients had limited ankle range of motion (ROM); mean ankle ROM in patients with PPC was lower than those without PPC (P = 0.006). Lower limb discrepancy was 2.5 cm in children, although three patients with PPC had a lower limb discrepancy measuring more than 2 cm, and five patients with PPC complained of postoperative pain.

CONCLUSIONS

Age and initial displacement are independent factors that increase the risk for PPC in children with MF fracture. Specifically, children aged under 11.5 years and those with initial displacement exceeding 4.5 mm are at a higher risk for PPC.

LEVEL OF EVIDENCE: Observational study.