A patient with a fused lumbar spine attempts a maximal effort lift of a heavy object. Which failure mode becomes most likely due to altered biomechanics?

💡 Explanation

Spinal fusion concentrates stress on vertebrae adjacent to the fused segments because the fused section is now rigid; therefore, adjacent segments undergo increased load. This heightened stress increases the risk of fracture in those areas, rather than affecting bone density or muscle activation.

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