Faculty Bibliography

OBJECTIVE: To demonstrate that after spinal cord injury (SCI) suppression of the parathyroid-vitamin D axis is associated with the degree of neurologic impairment and not the level of injury. DESIGN: A retrospective analysis of clinical and biochemical data obtained from hospital records of patients with SCI compared to a control group of patients with traumatic brain injury (TBI). SETTING: The inpatient rehabilitation unit of a tertiary care hospital. SUBJECTS: The medical records of 82 consecutive admissions to the rehabilitation unit with a diagnosis of SCI or TBI were reviewed. Patients with SCI were classified by the American Spinal Injury Association (ASIA) impairment scale and then grouped based on the completeness and level of injury. MAIN OUTCOME MEASURE: Comparisons of serum parathyroid hormone (PTH), 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D (1,25-D) were planned. Multiple comparisons were performed for total and ionized serum calcium levels, serum phosphorus levels, and 24-hour urinary calcium excretion rates to reflect changes in mineral homeostasis. Multiple comparisons were also performed for serum albumin, prolactin, thyroid function tests, and AM cortisol levels, as well as 24-hour urinary urea nitrogen and cortisol excretion rates to reflect metabolic responses to stress. RESULTS: Patients with SCI had significant suppression in PTH (p < .000009) and 1,25-D (p < .02) levels with elevated phosphorus (p < 0.03) and prolactin (p < .03) levels compared to patients with TBI. Also, more patients with SCI were hypoalbuminemic (p < .003) than patients with TBI. Patients with complete SCI (ASIA A) had more suppressed PTH (p < .03) and higher urinary urea nitrogen (p < .05) levels than SCI patients with incomplete injuries (ASIA B-D). Patients with complete, but not incomplete, SCI had lower albumin levels than patients with TBI (p < .05). These differences were not found between patients with tetraplegic and paraplegic SCI. ASIA motor scores did not correlate with any of the measured parameters but when used as a covariate did abolish differences in PTH and 1,25-D among the study groups by ANOVA. CONCLUSION: In patients with SCI, the degree of neurologic impairment, and not the level of injury, is associated with PTH suppression and markers of metabolic stress

Older patients who are referred for rehabilitation after undergoing orthopaedic procedures have numerous age-related conditions that may interfere with physical performance and safety. The general rehabilitation goals are to return each patient to the premorbid functional level of mobility and self-care, teach the exercises that are to be performed after hospital discharge, reduce the risk of falls, and ensure that the patient is discharged to a safe environment. Before elective surgery, the elderly orthopaedic patient should be instructed to perform breathing exercises to prevent pulmonary complications and active lower limb exercises to maintain good circulation and joint mobility, and be instructed in functional activities for mobilization in and out of bed. Postoperatively, the interdisciplinary rehabilitation team must facilitate early resumption of active exercises and self-care tasks and discourage prolonged bed rest and dependency on nursing staff and family members. Physical and occupational therapy should be provided to restore mobility and self-care functions. If discharge to home is planned, the home environment should be assessed and modifications recommended to reduce the risk of falls and ensure independent functioning to the extent possible. When the rehabilitation goals have been obtained, the patient should be discharged from the hospital, but additional therapy may be required, either at home or at an outpatient facility

The influence of the activities of daily living on human growth hormone (hGH) release and plasma insulin-like growth factor (IGF-I) levels is not known. Individuals with spinal cord injury (SCI) and paralysis generally have reduced levels of activity compared with ambulatory subjects. We studied sixteen subjects with SCI and sixteen nonSCI subjects matched for age, gender and body mass index (BMI) as controls. After an intravenous infusion of arginine hydrochloride (30 g/subject over 30 minutes), mean plasma hGH values at 30 and 60 minutes were significantly lower in the group with SCI compared with the control group (3.4 +/- 0.7 versus 10.7 +/- 2.5 ng/ml, p < 0.01; and 5.2 +/- 1.5 versus 12.5 +/- 2.7 ng/ml, p < 0.05). Also, peak and sum hGH responses were significantly lower in the group with SCI than in the control group (5.8 +/- 1.5 versus 14.1 +/- 2.8 ng/ml, p < 0.01; and 15.2 +/- 3.1 versus 34.8 +/- 7.2 ng/ml, p < 0.02). Controlling for age and BMI, the results remained significant. However, the mean plasma IGF-I level was significantly lower in SCI subjects younger than 45 years old than in the similar subgroup of age-restricted controls (202 +/- 19 versus 324 +/- 27 ng/ml, p < 0.05), whereas, a comparison of subgroups of subjects 45 years or older did not reveal a significant difference. These findings support the hypothesis that decreased daily physical activity results in depression of the hGH/IGF-I axis in younger individuals with SCI and may be considered to be a state of premature aging.(ABSTRACT TRUNCATED AT 250 WORDS)