Fig 1.
The Evo© short stem (A), Aramis© standard-length compactor (B), and Aramis© standard-lenght Stem (C). The proximal design is similar, the only difference is the length.
Table 1.
Length of Aramis© compactor and Evo© stems.
Fig 2.
Humeral draw of anteroposterior radiograph.
Stem axis deviation obtained by measuring the alpha angle (red circle, ) between the axis of the stem (orange line,
) and the axis of the humeral shaft (blue line,
).
Fig 3.
Humeral draw of anteroposterior radiograph.
Metaphyseal filling ratio (MR) and diaphyseal filling ratio (DR) obtained by calculating the ratio between the stem diameter (pink line, ) and the diaphysis diameter (green line,
). The measured distances are perpendicular to the axis of the humeral shaft. The MR is measured at the level of the cut, and the DR is measured 1 cm over the tip of the short-stem (dotted arrow,
), and at that same level for long stem (dashes arrow,
).
Fig 4.
True anteroposterior humeral radiographs showing well aligned implants (size 7), without cortical contact (A) trial (alpha angle 0,5°), (B) short-stem (alpha angle 0,1°), in the same subject.
Fig 5.
True anteroposterior humeral radiographs showing valgus positioned implants (size 7) (A) trial (alpha angle 6,8°) (B) short-stem (alpha angle 8,2°) in the same subject.
Table 2.
Patient (cadaver) age and measured implant variables for short humeral stems implanted with standard-length compactors.
Table 3.
Compactor and stem angular deviations compared between left and right shoulders.