Bone-mineral content, surface hardness, and mechanical fixation in the human radius. A correlative study

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiology

Background:

• Assessing bone quality is crucial for orthopedic screw fixation.
• Traditional methods for bone assessment can be invasive or inaccurate.

Purpose of the Study:

• To correlate non-invasively measured bone mineral content (BMC) and bone surface hardness with screw fixation strength in the human radius.
• To evaluate the clinical relevance of non-invasive bone density assessment for preoperative planning.

Main Methods:

• Seventeen intact radii from cadavers were scanned using photon-absorptiometry to determine BMC.
• Surgical screws were implanted into the radii, and extraction forces were measured.
• Correlation analysis was performed between BMC, surface hardness, and screw extraction force.

Main Results:

• A strong positive correlation (r ≥ 0.89) was found between BMC and screw extraction force.
• Bone surface hardness showed a weak correlation (r = 0.30) with screw extraction force.
• Non-invasive BMC measurement predicted screw-holding capacity within a 10% error.

Conclusions:

• Bone mineral content is a reliable predictor of screw fixation security in the radius.
• Non-invasive bone density measurement offers a safe and accurate method for preoperative assessment in patients requiring radius fixation.