High school cross country running injuries: a longitudinal study.

OBJECTIVE: To determine the incidence rate of injury among high school cross country runners over a 15-year period. DESIGN: Prospective-longitudinal. SETTING: Twenty-three high schools in western Washington State under the surveillance of the University of Washington Athletic Health Care System between 1979-1994. PARTICIPANTS: One hundred and ninety-nine cross country teams. MAIN OUTCOME MEASURE: Injuries resulting from running in a cross country practice or meet. RESULTS: There were 1,622 injuries for an overall injury rate of 13.1/1,000 athletic exposures (AEs), i.e., participation of a runner in a practice or meet. Girls had a significantly higher overall injury rate (16.7/1,000 AEs) than boys (10.9/1,000 AEs) (p < 0.0001). Girls also had significantly higher injury rates than boys for both initial (p < 0.0001) and subsequent injuries (p < 0.0001), especially those at the same body location (p = 0.0001). This difference in risk estimates was consistent over a 15-year period. Nearly three-fourths of the injuries resulted in < or =4 days of disability. Overall, higher rates of initial injuries were reported during practices (9.2/1,000 AEs) than in meets (7.8/1,000 AEs) (p = 0.04). Shin injuries had the highest overall rates of new injury (1.9/1,000 AEs) and reinjury at the same body location (53.9/1,000 AEs). Girls had significantly higher initial injury rates than boys for shin (p < 0.0001), hip. and foot injuries (p < 0.01), and higher reinjury rates for knee. calf, and foot injuries, respectively (p < 0.05). CONCLUSION: The results of this study suggest that girl cross country runners are at higher risk of injury and reinjury than boy cross country runners.

Wrestling.

Wrestling is considered one of the most physically demanding sports among high school and college athletics and, as such, has a proportionate number of injuries. Strength and endurance is paramount to successful performance. The wrestler needs to have not only strength and endurance, but also technical skill to be successful. Weight control and weight loss distinguish it from most other sports at the high school and collegiate levels. In addition to musculoskeletal problems, medical conditions and diseases impact the ability if the wrestler is to safely participate in this demanding but rewarding sport.

Isolated superior gluteal nerve injury: two case reports.

Isolated superior gluteal nerve injury has been infrequently described in the literature, mainly from injections or hip surgery. Its course through the greater sciatic foramen renders it at risk in pelvic or hip trauma. We report 2 cases of electromyographically documented isolated superior gluteal nerve injury following pelvic trauma. These cases illustrate that weakness in hip abduction following pelvic trauma may indicate the presence of a superior gluteal nerve injury, warranting further clinical and electrodiagnostic evaluation.

The effect of strength and endurance training on gait, balance, fall risk, and health services use in community-living older adults.

BACKGROUND: The study tested the effect of strength and endurance training on gait, balance, physical health status, fall risk, and health services use in older adults. METHODS: The study was a single-blinded, randomized controlled trial with intention-to-treat analysis. Adults (n = 105) age 68-85 with at least mild deficits in strength and balance were selected from a random sample of enrollees in a health maintenance organization. The intervention was supervised exercise (1-h sessions, three per week, for 24-26 weeks), followed by self-supervised exercise. Exercise groups included strength training using weight machines (n = 25), endurance training using bicycles (n = 25), and strength and endurance training (n = 25). Study outcomes included gait tests, balance tests, physical health status measures, self-reported falls (up to 25 months of follow-up), and inpatient and outpatient use and costs. RESULTS: There were no effects of exercise on gait, balance, or physical health status. Exercise had a protective effect on risk of falling (relative hazard = .53, 95% CI = .30-.91). Between 7 and 18 months after randomization, control subjects had more outpatient clinic visits (p < .06) and were more likely to sustain hospital costs over $5000 (p < .05). CONCLUSIONS: Exercise may have beneficial effects on fall rates and health care use in some subgroups of older adults. In community-living adults with mainly mild impairments in gait, balance, and physical health status, short-term exercise may not have a restorative effect on these impairments.

A comparison of the effects of three types of endurance training on balance and other fall risk factors in older adults.

We hypothesized that short-term endurance training improves balance in older adults, if training involves movements that "stress" balance. We tested the hypothesis by looking for a dose-response relationship between movement during exercise and balance improvement. The study was a single-blinded, randomized controlled trial. Subjects were sedentary adults (N = 106) aged 68-85 with at least mild deficits in balance. Exercise groups were: stationary cycle (low movement), walking (medium movement), and aerobic movement (high movement). Subjects attended supervised exercise classes three times a week for three months, followed by self-directed exercise of any type for three months. The primary test of the hypothesis compared changes in balance after three months of supervised exercise. One balance measure (distance walked on a six-meter narrow balance beam) improved in the hypothesized dose-response manner (cycle, 3% improvement; walking, 7% improvement; aerobic movement, 18% improvement: p < 0.02, test of trend). Other balance measures did not improve with exercise. Only walking exercise improved gait speed (by 5%, p < 0.02) and SF-36 role-physical score (by 24%, p < 0.05). VO2max improved with walking (18%, p < 0.004) and aerobic movement (10%, p < 0.01), but improved less with cycling (8%, p > 0.1). Leg strength improved significantly in all exercise groups. The study hypothesis was supported only for one balance measure. Only walking improved at least one measure of all major outcomes (endurance, strength, gait, balance, and health status), suggesting that walking is most useful for all prevention. Cycle exercise appeared least useful.

Factors associated with changes in gait speed in older adults.

BACKGROUND: The study addressed whether changes in gait speed in community-dwelling older adults were associated with changes in fitness (strength and aerobic capacity), physical health status, and/or depressive symptoms. METHODS: The study sample comprised 152 community-dwelling adults aged 68-85 who had participated in an exercise study. Study measures at baseline and 6-month follow-up included gait speed, a leg strength score, maximal aerobic capacity (VO2max), CES-Depression scale, and physical health status (SIP Physical Dimension). RESULTS: In cross-sectional regression analyses, leg strength, VO2max, weight, and the strength by VO2max interaction term were significant independent predictors of gait speed (R2 = 26%). Based upon the observed 7% increase in VO2max and 8% increase in strength in the exercise groups, the regression model predicted only a 2% (1.5 m/min) increase in gait speed, which did not differ significantly from the observed increase of 0% (.32 m/min). The strongest correlate of change in gait speed was change in CES-D scores (partial R = -.37). Change in physical health status also correlated with change in gait speed (partial R = -.28), while change in fitness did not. CONCLUSIONS: The results suggest, in the range of fitness of the study sample, that changes in gait speed are related to changes in depressive symptoms and physical health status, but not to modest changes in fitness. A model assuming nonlinear relationships may be appropriate for understanding how strength and aerobic capacity affect gait speed.

Isolated femoral mononeuropathy to the vastus lateralis: EMG and MRI findings.

A 16-year-old female track athlete experienced sudden onset of right anterolateral thigh pain, initially thought to be cramping. After 2 months of continued postexercise pain she sought medical evaluation. A 3-cm thigh circumference discrepancy was noted on physical exam. She was referred for electromyography (EMG) and magnetic resonance imaging (MRI) studies. Femoral and screening nerve conduction studies were normal. Needle EMG revealed acute neuropathic changes confined to the right vastus lateralis only. These findings were confirmed by MRI, including short T1 inversion recovery (STIR) sequences. All other medical work-up was normal, including lumbar and pelvic MRI, and complete serologic studies. This case represents a unique presentation of an idiopathic femoral mononeuropathy isolated to the vastus lateralis only, which has not been previously reported. The highly unusual anatomical presentation of this case illustrates the emerging complementary usefulness of EMG and MRI in delineating neuromuscular pathology.

Burn-associated peripheral polyneuropathy. A search for causative factors.

This study sought to evaluate the timing of burn-associated polyneuropathy (BAPN) and its relationship to burn severity or size. Seventeen burned subjects were studied 1 wk after thermal burns. Eleven subjects remained in the study to complete 6-wk follow-up studies. Nerve conduction studies were done on at least three nerves in two unburned limbs; results were numerically summarized by calculating Z scores for each parameter. A composite Z score, termed Ztotal, measured global nerve function. One week postburn, motor and sensory distal latencies were prolonged (mean Z, -0.72 and -0.85, respectively), motor conduction velocities slowed (mean Z, -1.31) and sensory nerve action potentials reduced in amplitude (mean Z, -0.66). Associations of Ztotal scores with total burn surface area and depth were not statistically significant. Those with severe neuropathy had higher levels of c-reactive protein (Spearman correlation, -0.624; P = 0.0129). There were no significant changes in Z scores at 6 wk. We conclude that BAPN is common after thermal injury, and the electrophysiologic manifestations of BAPN are present within the first week. Thermal injuries may induce an inflammatory cascade that results in alterations of nerve function.