We reviewed 60 custom-made femoral components of two different lengths : 12
5 mm (group A) and 100 mm (group B), in order to investigate the relationsh
ip between stem length and canal filling in uncemented custom-made total hi
p arthroplasty. There were no statistical differences between the two group
s in age, gender, height, body weight, canal flare index, or bowing angle o
f the femur. Postoperatively there was no statistical difference between th
e two groups in the proximal canal filling, but significant difference in t
he distal canal filling (75.5% vs 85.8% on the anteroposterior view and 76.
0% vs 82.5% in the lateral view, P<0.001). The distal canal filling inverse
ly correlated with the ratio of the proximal portion and the distal portion
of the stem curvature on the lateral view (lateral curve ratio of the stem
, P=0.002). We, conclude that superior filling at both the proximal and the
distal levels can be obtained by using 100-mm custom made components with
a small lateral curve ratio.