Why do children with spina bifida have a high risk of fractures?

Why do children with spina bifida have a high risk of fractures?

• A. Osteoporosis due to reduced bone mineral density
• B. Chronic infection weakening bones
• C. Increased bone remodeling with strong bones
• D. Local bone thickening from calcium deposition

Answer: (A)

The key idea is that fractures in children with spina bifida often come from bones that are less dense and weaker due to disuse, not from infection or abnormal bone growth. When mobility is limited by spinal involvement, bones in the legs and pelvis don’t bear as much weight. Mechanical loading stimulates bone formation, while not loading them enough leads to disuse osteoporosis—bones lose mineral density and become fragile. That reduced bone mineral density makes even minor bumps or stresses likely to cause fractures. Additional factors in spina bifida, like possible vitamin D deficiency, nutritional issues, and medications that affect bone metabolism, can contribute, but the core reason is low bone density from reduced loading. Chronic infection weakening bones isn’t the typical mechanism here, increased bone remodeling with strong bones would not explain fragility, and local bone thickening from calcium deposition would generally not cause this fracture pattern.

The key idea is that fractures in children with spina bifida often come from bones that are less dense and weaker due to disuse, not from infection or abnormal bone growth. When mobility is limited by spinal involvement, bones in the legs and pelvis don’t bear as much weight. Mechanical loading stimulates bone formation, while not loading them enough leads to disuse osteoporosis—bones lose mineral density and become fragile. That reduced bone mineral density makes even minor bumps or stresses likely to cause fractures. Additional factors in spina bifida, like possible vitamin D deficiency, nutritional issues, and medications that affect bone metabolism, can contribute, but the core reason is low bone density from reduced loading.

Chronic infection weakening bones isn’t the typical mechanism here, increased bone remodeling with strong bones would not explain fragility, and local bone thickening from calcium deposition would generally not cause this fracture pattern.