On the Polarstem broach, compaction is in which direction and cutting in which direction?

On the Polarstem broach, compaction is in which direction and cutting in which direction?

• A. Compaction M/L and Cutting A/P
• B. Compaction A/P and Cutting A/P
• C. Compaction M/L and Cutting M/L
• D. Compaction A/P and Cutting M/L

Answer: (D)

The key idea is that this broach uses two different actions in perpendicular planes: bone is compacted along the anterior-posterior axis to densify and create a stable shell, while bone is cut along the medial-lateral axis to shape the canal to the stem’s width. This combination gives a tight, stable fit by preserving bone density where bending loads act (front and back) and allowing controlled bone removal to achieve the correct medial-lateral contour. So compaction is in the anterior-posterior direction and cutting is in the medial-lateral direction.

The key idea is that this broach uses two different actions in perpendicular planes: bone is compacted along the anterior-posterior axis to densify and create a stable shell, while bone is cut along the medial-lateral axis to shape the canal to the stem’s width. This combination gives a tight, stable fit by preserving bone density where bending loads act (front and back) and allowing controlled bone removal to achieve the correct medial-lateral contour. So compaction is in the anterior-posterior direction and cutting is in the medial-lateral direction.