Developmental Pattern of Femoral Shortening Following Devascularization of the Capital Femoral Epiphysis in Piglets

Abstract

To investigate the developmental pattern of femoral shortening in Legg-Calve-Perthes disease, the authors made an experimental model of the disease in piglets by devascularizing the capital femoral epiphysis and following the piglets to skeletal maturity. The discrepancy first increased in the postoperative 0 to 8 weeks (1.2-1.9 mm of shortening per week), then decelerated for a considerable period during the postoperative 8 to 16 weeks (0.2-0.6 mm per week), and then increased again toward the end of the growth period of the postoperative 20 weeks (1.2 mm per week). The developmental pattern of femoral shortening showed an upward slope/plateau/upward slope pattern, as in type IV of the Shapiro classification. As the mechanism of the observed pattern, the authors presumed reduced epiphyseal height and growth retardation in the physis during the initial upward slope, a repair process at the plateau phase, and premature physeal closure during the second upward slope.

Animal Models of Osteonecrosis

“…By 20 weeks, there is severe deformity including marked collapse of the femoral head and acetabular dysplasia. This group also demonstrated that there were growth disturbances associated with an increase in femoral shortening over the 20-week time period [21]. Using growing minipigs, Schulitz et al [22] ligated all of the veins draining the femoral head.…”

Padronização de modelo animal para o estudo da necrose isquêmica da cabeça femoral na doença de Legg-Calvé-Perthes

“…Também, propõem-se introduzir os testes de avaliação da marcha para análise funcional. [11][12][13][14][15][16][17][18] deformidade da CF é mais evidente a partir deste período de isquemia. 11 Operaram-se onze leitões, híbridos comerciais (cruzamento das raças Large White e Landrace), machos, pesando entre 4 e 6 kg, idade de 3 a 4 semanas.…”

The Long Term Results of Femoral Varus Osteotomy in Patients with Legg-Calve-Perthes Disease

“…One concern, however, was that it further shortened the affected leg and thus increased the need for the epiphyseal arrest of the normal opposite leg 9, [20][21][22] . It is generally accepted that the amount of the shortening of the affected legs in LCPD depends almost exclusively on the severity of inhibition of endochondral ossification in the proximal femoral growth plate.…”

“…However, the disadvantages of FVO are also reported that it may shorten the limb and may create excessive varus angulation, leading to weakness of the abductors of the hip 19,21,24) . However, only few papers have been reported the long term results of FVO which followed up to the full skeletal maturity.…”

“…It is generally accepted that the amount of the shortening of the affected legs in LCPD depends almost exclusively on the severity of inhibition of endochondral ossification in the proximal femoral growth plate. In addition, the loss of epiphyseal height, disuse atrophy of the diseased limb, and performing FVO in older children are considered to contribute to the shortening of the affected leg 21,22) . However, the incidence and the amount of residual shortening following LCPD vary widely in the literature.…”