The primary feature on the Polarstem broach that allows for an optimal fit between the stem and cortical bone is which of the following?

The primary feature on the Polarstem broach that allows for an optimal fit between the stem and cortical bone is which of the following?

• A. Expansion A/P and Polishing M/L
• B. Compression A/P and Boring M/L
• C. Shaping A/P and Ripping M/L
• D. Compaction A/P and Cutting M/L

Answer: (D)

Achieving a stable, precise fit for a Polarstem relies on how the bone is prepared to seat the implant firmly against the cortical walls. Compaction in the anterior-posterior direction densifies the bone near the canal walls, creating a strong press-fit that helps hold the stem securely without cement. Cutting in the medial-lateral direction shapes the canal so the stem can seat cleanly and contact the bone evenly around its circumference, reducing tilting and micromotion. This combination—densifying bone front-to-back while shaping side-to-side—provides the best balance of stability, alignment, and preservation of bone stock. Other approaches that expand, bore, or polish don’t produce the same reliable press-fit and may compromise fixation.

Achieving a stable, precise fit for a Polarstem relies on how the bone is prepared to seat the implant firmly against the cortical walls. Compaction in the anterior-posterior direction densifies the bone near the canal walls, creating a strong press-fit that helps hold the stem securely without cement. Cutting in the medial-lateral direction shapes the canal so the stem can seat cleanly and contact the bone evenly around its circumference, reducing tilting and micromotion. This combination—densifying bone front-to-back while shaping side-to-side—provides the best balance of stability, alignment, and preservation of bone stock. Other approaches that expand, bore, or polish don’t produce the same reliable press-fit and may compromise fixation.