Bone remodeling, around an anatomical hip stem: a one year prospective study using DEXA.

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Bone Physiology

Background:

• Periprosthetic bone loss in the proximal femur can lead to hip prosthesis failure.
• Bone remodelling around implants is a significant factor in long-term implant success.
• Understanding bone density changes is crucial for evaluating new hip stem designs.

Purpose of the Study:

• To evaluate the one-year behavior of the ANATO® stem, a redesigned hip prosthesis.
• To assess bone densitometry changes around the ANATO® stem in patients with primary coxarthrosis.
• To compare the remodelling patterns based on patient demographics and BMI.

Main Methods:

• Prospective, controlled study involving 61 patients with primary coxarthrosis.
• Densitometric analysis of bone mineral density (BMD) in Gruen zones around the ANATO® stem.
• Comparison of BMD changes against the healthy contralateral hip as a control.

Main Results:

• A statistically significant decrease in bone mineral density of -5.9% was observed in zone seven after one year.
• No significant differences in bone remodelling patterns were found concerning sex, age, or body mass index (BMI).
• The ANATO® stem demonstrated effective load transmission to the proximal femur.

Conclusions:

• The ANATO® stem facilitates efficient load transfer, minimizing stress shielding.
• Significant bone atrophy was localized to zone seven, indicating a specific remodelling response.
• Patient-specific factors like age, BMI, and sex do not appear to influence bone remodelling around the ANATO® stem.