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In this report, we applied diffusion tensor imaging (DTI) methods in 36 patients with uncomplicated mild traumatic brain injury (mTBI) and a comparison group of 37 participants with orthopedic injury. Our aim was to characterize regional and global macro- and microstructural attributes of white matter (WM), gray matter (GM), in addition to volume and diffusivity of cerebrospinal fluid (CSF) to identify and differentiate patterns of acute and short-term recovery. Given that previous DTI reports on mTBI in adults using a region-of-interest approach implicated the corona radiata (CR), corpus callosum, and hippocampus, we analyzed and quantified DTI metrics of these regions using atlas-based methods. The normalized volume percentages of global CSF, GM, and WM were not different between the mTBI and orthopedic comparison (OC) groups at either the baseline or follow-up time points or between the baseline and follow-up time points within the OC group (p0.17; uncorrected for multiple comparisons). The DTI metrics did not differ between groups at either occasion. However, an increase was noted on follow-up in the OC group in the global mean diffusivity of GM (uncorrected p=0.003) and WM (uncorrected p=0.02), indicating a decrease in diffusivity at the 3-month postinjury, as compared to the baseline scan. An analysis of the DTI data collected longitudinally in the CR show insignificant changes in the OC group (p0.08; N=37). CR radial diffusivity was found to be elevated in the between-group comparison at baseline (mTBI1 vs. OC1), but did not differ in the within-group comparison (mTBI1 vs. mTBI2; N=19), suggesting the possible resolution of edema. Our analysis of the cross-sectional and follow-up data, which is uncorrected for multiple comparisons, demonstrates dissociation between volumetric (macrostructural) and tissue integrity (microstructural) attributes and shows the potential utility of DTI to capture transient edema in the CR.

Summary: Damage and/or disconnection of the primary somatosensory cortex (SI) after stroke leads to deficits in touch perception. We used magnetoencephalography to test whether specific patterns of functionality of the somatosensory cortex are associated with different degrees of postacute somatosensory deficit. Nineteen postacute unilateral stroke patients suffering different degrees of somatosensory deficit (six inexistent, six moderate, and seven severe) and eight aged-matched controls underwent high-resolution MRI and whole-head magnetoencephalography recordings of somatosensory-evoked fields and of spontaneous slow oscillatory activity. Amplitude of SI activation after tactile stimulation in the affected and nonaffected hemispheres and delta dipole density (DDD) in the postcentral areas were estimated and compared across the four groups. Severe postacute somatosensory deficit was accompanied, in all cases, with absence of SI responses to stimulation in the affected hand and a significant asymmetry in postcentral DDD toward the affected hemisphere. Patients with moderate sensory loss showed asymmetry in their postcentral DDD (four cases toward the affected hemisphere and two toward the unaffected) but no atypical amplitudes in SI activation. Recordings in stroke patients without somatosensory deficit did not differ from those obtained in controls for SI amplitude or postcentral DDD. In stroke patients, amplitude of SI responses and postcentral DDD show a negative correlation. Lack of activation of SI cortex after stimulation of the affected hand and spontaneous slow oscillatory activity in postcentral areas are neurophysiological correlates of somatosensory deficit in the postacute phase of stroke.

To determine differences between dalteparin and enoxaparin in patients with spinal cord injury.This prospective, randomized, open-label study was performed as a multiple hospital trial in a large urban setting. A total of 100 patients with acute (3 mo) spinal cord injury were recruited. A total of 95 patients met all inclusion criteria. Fifty received enoxaparin, and 45 received dalteparin. Main outcome measures included deep venous thrombosis, bleeding, compliance, Short Form-12 Health Status Survey, satisfaction, and medication/labor costs. Patients were randomized to receive 30 mg of enoxaparin subcutaneously every 12 hr or 5000 IU of dalteparin subcutaneously once daily. Prophylaxis was continued for 3 mo for motor-complete and 2 mo for motor-incomplete patients.Six percent of the patients developed deep venous thrombosis while receiving enoxaparin and 4% while receiving dalteparin (chi2 = 0.44, df = 1, P = 0.51). Four percent developed bleeding while receiving dalteparin and 2% while receiving enoxaparin (chi2 = 0.13, df = 1, P = 0.72). No differences were noted in compliance, health status, or most of the satisfaction measures. It was, however, noted that after being discharged home, the patients receiving enoxaparin rated the shots significantly more inconvenient (two injections per day) compared with taking three pills per day, than those receiving dalteparin (one injection per day, P0.05). The cost of the medication was 1101 US dollars/mo for enoxaparin (two injections per day) and 750 US dollars/mo for dalteparin (one injection per day).Similar compliance, health status, deep venous thrombosis, and bleeding rates were found between dalteparin and enoxaparin.

Moussavi RM, Garza HM, Eisele SG, Rodriguez G, Rintala DH. Serum levels of vitamins A, C, and E in persons with chronic spinal cord injury living in the community. Arch Phys Med Rehabil 2003;84:1061-7. Objectives: To determine serum levels of vitamins A, C, and E among individuals with spinal cord injury (SCI) living in the community, to compare these levels with general population norms, and to assess their association with demographic and injury-related data (age at onset, time since onset, level and completeness of injury), function, nutritional behaviors, and health status. Design: Descriptive and correlational. Setting: General community. Participants: A total of 110 adults (≥18y) with traumatic SCI of at least 2 years in duration living within a 13-county area in Texas. Interventions: Not applicable. Main Outcome Measures: Demographic information, age at onset, time since onset, American Spinal Injury Association (ASIA) total motor index score, ASIA impairment score, assay of serum vitamins, FIM™ instrument motor items, Health-Promoting Lifestyle Profile nutrition subscale, Medical Outcomes Study 36-Item Short-Form Health Survey general health subscale, and pressure ulcer occurrence in past 12 months. Results: Many (16%–37%) of the participants had serum levels below the reference range for each vitamin. Being older at onset or less impaired was associated with higher serum vitamin A levels. Higher levels of serum vitamin A also were related to better function and health status and with not having a pressure ulcer within the past 12 months. Being older or older at onset was associated with higher serum levels of vitamin E. No relationships with vitamin C were found. Conclusions: Vitamin levels may be related to function, general health, and pressure ulcer incidence in persons with SCI. Further study is needed to determine effective interventions to improve vitamin levels and determine the effect of such improvements on overall health and rehabilitation outcomes.

Immediately after the trauma, spinal cord injury patients have an increased rate of collagen synthesis and an even greater increase of collagen degradation. Collagen lost from bone is implicated in the etiology of osteoporosis and heterotopic ossification, and collagen lost from skin might lead to a propensity to develop pressure ulcers. The urinary excretion of two collagen metabolites has been monitored and their fluctuation related to the onset of skin or bone complications in these patients. One metabolite, glucosyl-galactosyl hydroxylysine, is more abundant in skin collagen; the other, galactosyl hydroxylysine, is more abundant in bone collagen. The excretion of both metabolites increases after injury, reaching a peak between three and six months after injury, and declines gradually, reaching control values about a year after injury. If a skin pressure ulcer develops, the urinary excretion of the diglycoside remains elevated instead of gradually decreasing. Similarly, if osteoporosis or heterotopic ossification is diagnosed, the monoglycoside excretion does not return to control values until the bone turnover stabilizes. Monitoring of the urinary excretion of both glycosides might prove helpful in prompting early examination to establish the presence of emerging skin and bone complications. Thus, aggressive preventive therapy could be given sooner.