Traumatic brain injury (TBI) is a major public health issue, and yet medical science has little to offer for the persistent symptoms that prevent many of these individuals from fully re-entering society. Post-traumatic hypopituitarism, and specifically growth hormone deficiency (GHD), has been found in a large percentage of individuals with chronic moderate to severe TBI. Presently, there are no published treatment studies of hormone replacement in this population. In this study, 83 subjects with chronic TBI were screened for hypopituitarism. Forty-two subjects were found to have either GHD or GH insufficiency (GHI), of which 23 agreed to be randomized to either a year of GH replacement or placebo. All subjects completed the study with no untoward side effects from treatment. A battery of neuropsychological tests and functional measures were administered before and after treatment. Improvement was seen on the following tests: Dominant Hand Finger Tapping Test, Wechsler Adult Intelligence Scale III-Information Processing Speed Index, California Verbal Learning Test II, and the Wisconsin Card Sorting Test (executive functioning). The findings of this pilot study provide preliminary evidence suggesting that some of the cognitive impairments observed in persons who are GHD/GHI after TBI may be partially reversible with appropriate GH replacement therapy.

Objective-To examine the importance of cardiorespiratory conditioning after traumatic brain injury (TBI) and provide recommendations for patients recovering from TBI.Method-Review of literature assessing the effectiveness of endurance training programs.Main outcomes and results-A sedentary lifestyle and lack of endurance are common characteristics of individuals with TBI who have a reduction in peak aerobic capacity of 25-30% compared to healthy sedentary persons. Increased physical activity and exercise training improves cardiorespiratory fitness in many populations with physical and cognitive impairments. Therefore, increasing the endurance and cardiorespiratory fitness of persons with TBI would seem to have important health implications. However, review of the TBI literature reveals that there have been few well-designed, well-controlled studies of physiologic and psychological adaptations of fitness training. Also lacking are long-term follow-up studies of persons with TBI.Conclusions-Assessing endurance capacity and cardiorespiratory fitness early in the TBI rehabilitation process merits consideration as a standard of care by professional rehabilitation societies. Also, providing effective, safe and accessible training modalities would seem to be an important consideration for persons with TBI, given the mobility impairments many possess. Longterm follow-up studies are needed to assess the effectiveness of cardiorespiratory training programs on overall morbidity and mortality.

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Study Design: A direct comparison of synchronous versus asynchronous arm crank ergometry has not been carried out previously. Therefore, a comparative research design was employed. Objective: To assess the physiological responses of arm cranking when performed asynchronously (arms moving opposite to each other) versus synchronously (both arms moving in the same direction simultaneously). Setting: A university hospital setting in Galveston, Texas, USA. Methods: Seventeen individuals between the ages of 19 and 53 years were studied, 11 with paraplegia and six with no apparent disability. Two maximal arm crank graded exercise tests were performed with the subject seated in a wheelchair. Testing consisted of both arms (1) asynchronously (reciprocally) pushing and pulling the crank handles and (2) pushing and pulling the crank handles synchronously. Each test consisted of 2 min stages starting at 20 W and increasing 10 W per stage thereafter until exhaustion. Heart rate, oxygen consumption, and minute ventilation were measured and recorded during each stage. Blood lactate levels were monitored before and after each test. Statistical analysis was performed using the multivariate Hotelling's T 2 followed by post hoc univariate tests. Results: Greater power and longer test times (both groups, P50.05) and higher post test blood lactates (nondisabled P50.01, paraplegic P50.05) were achieved with asynchronous cranking versus synchronous cranking. While submaximal responses were similar between the two modes of cranking, there was a tendency for all variables to be lower with asynchronous. All subjects preferred asynchronous rather than synchronous cranking. Conclusion: Despite few statistically signi®cant dierences, based on the subjective reports from all subjects, we believe there is a clinically signi®cant dierence between the two modes of cranking. The results suggest that the mode of cranking may have implications for arm crank testing, training, and functional locomotion in individuals with lower extremity impairments.

Static standing balance is commonly measured with research laboratory systems (LabSys) or clinical systems (ClinSys). The purposes of this study were to (1) assess the reliability of two systems designed to measure static standing balance in nondisabled children, (2) compare the findings derived from the two systems of measurement, and (3) examine the relationship between anthropometric measures and postural sway. Twenty-five nondisabled children (12 male, 13 female) ages 1 year 11 months to 12 years 2 months (mean = 6 years 4 months; SD = 4 years 3 months) participated in the study. Each child stood on the LabSys and the ClinSys for three consecutive 10 second measurement periods. Intraclass correlation coefficients (ICC (2, 1)) for the three trials on each system were 0.62 (LabSys) and 0.63 (ClinSys). The level of agreement between the two systems was 0.61 (ICC (2, 1)). Younger children exhibited more variability and less agreement between measurement trials using the ClinSys. However, older children demonstrated more similar sway indices when comparing the two systems of measurement. Two-way analysis of variance indicated that there were significant differences between sway indices measured by the two systems (p < 0.01) and between the youngest children (aged 2-4 years) and all other children (p < 0.01). In addition, agreement among trials for the two systems was different depending on the age group measured. Correlation coefficients for sway index and age, height, weight, and foot length ranged from -0.52 to -0.64 for the LabSys (p < 0.01) and -0.62 to -0.73 for the Clin-Sys (p < 0.01). Stepwise multiple regression analysis indicated that height was the most significant predictor of sway when measured by the ClinSys (R2 = 0.536, p < 0.01) whereas age was the most significant predictor when sway was measured using the LabSys (R2 = 0.403, p < 0.01). The results suggest that the degree of postural sway and the reliability of the measurement itself are influenced by the age of the child and the measurement system employed.

All measures correlated well with peak Vo(2), establishing an acceptable level of criterion-related (concurrent) validity. The addition of heart rate and calculating the PCI was only slightly better at predicting peak Vo(2), albeit nonsignificant, than a simple measure of total distance. The 6MWT provides a good estimate of peak aerobic capacity, and some measures are more responsive to change than others in patients recovering from TBI.

Distance traveled and the physiologic cost index demonstrated excellent reliability, whereas heart rate responses for individual minutes demonstrated only fair reliability. The individuals studied were very consistent in their efforts, despite a combination of physical and cognitive impairments. The results suggest that the 6-min walk test can be used reliably in the assessment of functional ambulation in persons with acquired brain injury.

This study shows that individuals with traumatic brain injury with normal GH secretion have below normal aerobic capacity and those patients who have GH insufficiency/deficiency are further deconditioned. Studies of GH replacement in these subjects should be conducted to assess whether GH therapy can improve cardiorespiratory fitness and prevent secondary disability.