Femoral head-neck diameter and ratio in Thais: a cadaveric study.

OBJECTIVE

To report the femoral head and neck diameter in both coronal and sagittal planes, the femoral head-neck ratio, and the difference between sex in a normal Thai population.

MATERIAL AND METHOD

One hundred two femoral bones without visible previous disease or deformity of the head, neck, and shaft that included 50 male donors and 52 female donors, with an average age of 58.8 years (range 25 to 85) were included in the present study. The measurement of the femoral head and neck diameters was performed by using Vernier calipers (scale 150 x 0.02 mm).

RESULTS

The mean head and neck diameters in coronal and sagittal planes in male and female are 45.25, 45.23, 40.28, 40.13 mms (p = 0.000), and 30.80, 25.65, 27.79, 22.08 mms (p = 0.000), respectively. The head-neck ratio in each plane in both male and female are 1.47, 1.45 (p = 0.257), and 1.77, 1.83 (p = 0.016), respectively.

CONCLUSION

The very small average diameter of femoral head, especially in Thai females, should warn surgeons to carefully consider and then, perform hip resurfacing arthroplasty to avoid early complication from neck notching and mal-position. The head-neck ratio of the present study group is high enough to anticipate that postoperative anterior impingement of the neck and acetabulum or limiting hip flexion is unlikely to occur.