Table 3 Comparison of prostheses measurements between the loosening group and control group

Osteotomy ratio [%, (\(\overline{x }\) ± S)]

46.06 ± 0.11

44.24 ± 28.08

0.307

0.762

The length ratio of the extramedullary and intramedullary parts of the femoral prostheses [%, (\(\overline{x }\) ± S)]

96.27 ± 28.08

108.51 ± 74.38

 − 0.469

0.644

The ratio of prostheses length to femur length [%, (\(\overline{x }\) ± S)]

71.89 ± 6.62

80.75 ± 8.39

 − 2.672

0.014

The ratio of intramedullary stem diameter to femoral diameter [%, (\(\overline{x }\) ± S)]

25.50 ± 6.90

35.06 ± 12.18

 − 2.457

0.014

Growth ratio of intramedullary stem length^a [%, (\(\overline{x }\) ± S)]

3.61 ± 7.23^b

10.45 ± 21.23^b

 − 0.615

0.551

Growth ratio of intramedullary stem diameter [%, (\(\overline{x }\) ± S)]

3.95 ± 4.59^b

28.78 ± 26.71^b

 − 1.804

0.099