Intramedullary Nailing for Lower Limb Polyostotic Fibrous Dysplasia in Children: A Long-term Follow-up Study

Abstract

Background: In children, intramedullary nailing (IN) has been proposed as the best treatment when the femur and tibia are totally affected by fibrous dysplasia (FD). However, in younger children IN must be repeated to maintain stabilization of the affected skeletal segment during growth. We report the long-term results in a cohort of patients in whom more than two-thirds of cases had IN repeated during growth.

Methods: Twenty-nine femurs and 14 tibias totally affected by FD were treated by IN in 21 patients with polyostotic FD and McCune-Albright syndrome. Thirteen patients with 35 femoral and tibial deformities had a painful limp whereas 8 presented fractures. The patients had their first IN at a mean age of 9.26±2.68 years (range: 4 to 14 y). IN was repeated during growth in the younger patients, and all the patients underwent a mean of 2.13 femoral and 1.50 tibial IN per limb. The last IN was performed at a mean age of 16.42±1.95 years (range: 11 to 19 y). Titanium elastic nails and adult humeral nails were used in younger children, whereas adult femoral cervicodiaphyseal and interlocking tibial nails were used in older children and adolescents. At the latest follow-up, the patients were evaluated with a clinicoradiographic scale. All the data were statistically analyzed.

Results: The mean length of follow-up from the last IN was 6.47±3.10 years (range: 3 to 14 y), and the mean age of the patients at follow-up was 22.85±3.53 years (range: 14 to 29 y) when lower limbs were fully grown in all but 1 patient. Satisfactory long-term results were obtained in about 81% of our patients, while complications occurred in 32.5% of the 43 cases.

Conclusion: Lower limb IN-that was repeated in younger children during growth-provided satisfactory long-term results in most of our patients, with fracture and deformity prevention and pain control, regardless of the high rate of complications that mainly affected the femoral cases. Missing scheduled follow-ups was the main predictor of a poor result.

Level of evidence: Level IV-case series.

FIGURE 1

The 6 types of femoral deformities on the coronal plane according to Ippolito et al.

FIGURE 2

A, Type 1 femoral deformity in a 4-year-old girl affected by McCune-Albright syndrome causing a severe painful limp. B, One year after nailing with titanium elastic nails (TENs), pain had disappeared. C, Five years later, the painful limp recurred after marked femoral growth with relative shortening of the TENs that were removed and replaced with an adult cervicodiaphyseal nail (D). E, At the latest follow-up, 7 years after the third nail replacement, the patient was 21 years old and fully asymptomatic.

FIGURE 3

A, Patient with severe bilateral coxa vara with a painful waddling gait; bilateral valgus hip osteotomy (B) was performed. C, Standing radiograph at 6 years of age with type 4 femoral deformities. D, At 10 years of age, 4 years after bilateral femoral intramedullary nailing with adult humeral nails, bilateral coxa vara recurrence, and relative shortening of the nails with growth were evident (E).

FIGURE 4

A, The same patient illustrated in Figure 3 at 11 years of age after intramedullary nailing (IN) with adult femoral nails and coxa vara correction. B, Two years later, after IN for fracture of both tibias. A severe coxa vara recurrence was treated by a 2-stage procedure (C, D) at the age of 14 years. E, At the latest follow-up, 4 years after the last IN, he had a lower limb length discrepancy of 1.5 cm and the mechanical axis was deviated in valgus of 3 degrees on the right and 5 degrees on the left. He walked with a slight limp without pain. Good result.

FIGURE 5

A and B, Five-year-old boy with McCune-Albright syndrome and monomelic involvement. He had a 50 degrees coxa vara and genu valgum, with a marked limp. C, Two years later, after a 2-stage correction of the femoral deformity and genu valgum correction by medial epiphysiodesis of the knee. When admitted for removal of both the loosened locking screw and the femoral 8-plate, the neck-shaft angle of the right femur measured 120 degrees and the right knee was straight. D, Lost for several years to follow-up, the patient accepted to participate in the study at the age of 14 years, showing deformities recurrence. He was the only patient with physes still open at the latest follow-up. Poor result.

FIGURE 6

A, Standing anteroposterior radiograph of the pelvis and femurs of a 15-year-old patient with McCune-Albright syndrome, 2 years after her last bilateral intramedullary nailing. The patient was lost to follow-up but, 14 years later, she accepted to participate in the study. Radiographs (B) showed a severe recurrence of the femoral deformities with nail migration. She had a severe painful limp, but she was able to walk without any aid. Poor result.