A person fell from a high area and landed on their feet, resulting in a spinal cord injury. Which type of spinal cord injury did the person sustain?

Choice A reason: Facial trauma may increase aspiration risk if swallowing is impaired, but a 21-year-old typically has a robust immune system, reducing pneumonia risk. The trauma does not directly compromise lung defenses or immune function significantly, making this individual less likely to develop pneumonia compared to an immunocompromised person.

Choice B reason: Osteoarthritis and chronic knee pain in a 72-year-old may limit mobility, slightly increasing pneumonia risk due to reduced lung expansion. However, this condition does not directly impair immune function or lung clearance mechanisms, making it a lower risk compared to immunodeficiency, which severely predisposes to infections.

Choice C reason: Elevated cholesterol in a 48-year-old increases cardiovascular risk but does not directly affect lung function or immune response to infections. Without respiratory or immune compromise, this individual has a lower risk of pneumonia compared to someone with a primary immunodeficiency disorder, making this choice incorrect.

Choice D reason: A 69-year-old with a primary immunodeficiency disorder has a severely compromised immune system, impairing the ability to fight respiratory infections like pneumonia. Age-related lung changes and reduced immune response increase susceptibility to pathogens, making this individual at the highest risk for developing pneumonia, which is why this is correct.

Choice A reason: Excessive plasma proteins increase oncotic pressure, pulling fluid into the vascular space, reducing edema. Edema occurs with low plasma proteins (e.g., hypoalbuminemia), as in liver or kidney disease, which decreases oncotic pressure, causing fluid leakage, making this choice incorrect.

Choice B reason: Lymph node dysfunction impairs lymphatic drainage, leading to fluid accumulation in tissues, causing edema (lymphedema). The lymphatic system normally returns interstitial fluid to circulation, so its failure results in swelling, particularly in extremities, making this the correct cause of edema.

Choice C reason: Decreased capillary permeability reduces fluid leakage into tissues, preventing edema. Edema occurs with increased permeability, as in inflammation, allowing fluid to escape into the interstitial space, making this choice incorrect as it opposes the mechanism of edema formation.

Choice D reason: Decreased capillary hydrostatic pressure reduces the force pushing fluid out of capillaries, decreasing edema. Edema is caused by increased hydrostatic pressure, as in heart failure, which forces fluid into tissues, making this choice incorrect for causing edema.