Fig. 9From: Stress distributions of the short stem and the tapered wedge stem at different alignments: a finite element analysis studyComparison of moment arm between models with flexion and extension stem positions. a Flexion. b Extension. The moment is larger in extension than in flexion because of the longer moment arm l. The moment due to the downward load component in flexion is working in the opposite direction; therefore, the composite moment is smallerBack to article page