Skeletal involvement in type 1 Gaucher disease: Not just bone mineral density

Area of Science:

• Orthopedics and Bone Metabolism
• Rare Genetic Diseases
• Medical Imaging and Diagnostics

Background:

• Gaucher disease (GD) involves multi-organ infiltration, leading to significant skeletal complications like deformities, osteopenia, fractures, and avascular osteonecrosis.
• Bone quality, encompassing microarchitecture and geometry, is crucial for bone strength and assessing skeletal disease severity in Gaucher disease.
• Current assessment often focuses on bone mineral density (BMD), potentially missing nuances in bone quality relevant to GD complications.

Purpose of the Study:

• To noninvasively evaluate bone quality in type 1 Gaucher disease patients using advanced dual-energy X-ray absorptiometry (DXA) tools.
• To determine if bone quality parameters can differentiate Gaucher disease patients with specific skeletal complications (fractures, infarctions, avascular osteonecrosis).
• To assess the combined utility of bone quality and quantity (BMD) in identifying severe skeletal involvement in Gaucher disease.

Main Methods:

• Studied 23 type 1 Gaucher disease patients on enzyme replacement therapy, assessing skeletal complications including pathological fractures, bone infarctions, and avascular osteonecrosis.
• Employed two innovative DXA-based tools: Trabecular Bone Score (TBS) for trabecular microarchitecture and Hip Structural Analysis (HSA) for macroscopic geometry.
• Analyzed associations between bone quality parameters (TBS, HSA metrics) and bone quantity (BMD) with the presence of skeletal complications.

Main Results:

• Trabecular Bone Score (TBS) was significantly lower in patients with avascular osteonecrosis (p=0.049) and pathological fractures (p=0.024).
• Hip Structural Analysis (HSA) parameters, specifically Cross Sectional Area and Buckling Ratio in the intertrochanteric region and narrow neck, distinguished patients with avascular osteonecrosis.
• Bone mineral density (BMD) was low in 50% of patients; neither BMD nor HSA correlated with pathological fractures, highlighting limitations of traditional measures.

Conclusions:

• Bone quality assessment using TBS and HSA provides valuable insights into skeletal complications in Gaucher disease, complementing traditional BMD measurements.
• Trabecular microarchitecture (TBS) and hip structural geometry (HSA) can identify Gaucher disease patients at higher risk for specific skeletal issues like avascular osteonecrosis and fractures.
• A combined evaluation of bone quality and quantity is recommended for a comprehensive assessment of skeletal involvement and severity in Gaucher disease patients.