Table 1 Patient demographics

Gender

27 male (33 hips) and 8 female (9 hips)

Mean age

27.5 ± 3.7 years (range 20.3 to 35.8 years)

Mean height

167 ± 6.8 cm(165.5 ± 7.6 cm)

Mean weight

62.7 ± 3.6 kg (61.5 ± 7.1 kg)

BMI

20.2 kg/m² (range, 16.8–23.2 kg/m²)

Disease

Rheumatoid arthritis (RA) in 20 hips (25 patients), ankylosing spondylitis (AS) in 10 hips (12 patients), osteoarthritis in 5 hips (5 patients)

Follow-up time

5.5 ± 1.1 years (range, 3.0–8.0 years)

Femoral cavity

0.76 ± 0.30 (range 0.67 to 0.92)

Femoral canal dimension(isthmus)

18.7 ± 2.6 mm (range 15.8 to 22.6 mm)

Femoral stem prosthesis subsidence in the last follow-up

0.39 ± 0.21 (range 0.22 to 0.47)