Zinc and osteoporosis in patients with spinal cord injury

Thirty-eight patients (8 women and 30 men) with spinal cord injury were investigated. All had been immobilised after the traumatic event. The time elapsed since their accidents varied from 2 to 74 weeks. Blood and urine samples were collected to investigated calcium, zinc, magnesium, sodium, alkaline phosphate, phosphore, haemoglobin, creatinine, uric acid and proteins in blood, and the urinary excretion of phosphore, hydroxyproline, creatinine, amino acids, calcium, calcium, magnesium and zinc. The methods were estimately by atomic absorption spectrophotometry. The serum zinc levels did not differ statistically from normal and the calcium and magnesium levels in the serum were lower among the patients than in normal controls. The urinary excretion of zinc, calcium, phosphore and hydroxyproline was higher among the patients without correlation to the patients' age. The zinc excretion is negatively correlated to the time elapsed since the injury, but it is still high 3 months after trauma. The highly significant correlation between urinary zinc and hydroxyproline excretion, together with increased calcium and phosphore excretion, suggests that zinc may be involved in the process of osteoporosis in patients with spinal cord injury.