Biomedical subjects
W O Roberts
Publications and source records attributed to W O Roberts.
Paradoxical emboli in patent foramen ovale.
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A 12-yr profile of medical injury and illness for the Twin Cities Marathon.
OBJECTIVE: To summarize the medical encounters (injury/illness) for runners and the meteorologic data collected in the medical area of a large marathon race. DESIGN: Prospectively transcribed medical records were analyzed for encounter rate, injury/illness type, treatment rendered, and outcomes. The environmental conditions for each race day are compared with injury/illness rates and types. SETTING: An urban 42-km marathon located at 44 degrees 53' N latitude and 93 degrees 13' W longitude, scheduled on the first Sunday of October with an early morning start time. PARTICIPANTS: 81,277 entrants in the Twin Cities Marathon from 1982 to 1994. MAIN RESULTS: The start temperature range was -4 to 16 degrees C and the 4-h temperature range was 5-20 degrees C. The average dew point was 3 degrees C at the start and 4 degrees C at 4 h. The finish area medical encounter rates for marathon runners were 18.9 per 1000 entrants and 25.3 per 1000 finishers. Mild injury/illness accounted for 90% of finish line medical encounters. Runners presented with exercise-associated collapse (59%), skin problems (21%), musculoskeletal problems (17%), and other medical problems (3%). Only 112 runners received intravenous fluids and 30 runners were transferred to emergency medical facilities. One death occurred in 1989. CONCLUSIONS: Marathon racing in cool conditions is a safe activity and most of the medical encounters are of minor severity. An early morning start time contributes to a cool racing environment and a low injury rate. More than 99.9% of runners who finish this race leave the finish area without hospital or emergency room care. The injury/illness profile can be used to tailor medical care at the finish area of marathons.
Youth ice hockey tournament injuries: rates and patterns compared to season play.
OBJECTIVE: To prospectively document the incidence of game injury rates in youth ice hockey tournaments to compare with season-long game injury rates and to analyze the injuries occurring at tournaments by mechanism, type, body location, severity, player position, and period of play. DESIGN: A prospective injury report form completed for injured players by the tournament athletic trainer. SETTING: Four boys' tournaments and one girls' tournament during the 1993-94 season. PARTICIPANTS: 807 boys and girls, ages 9-19. MEASUREMENTS/MAIN RESULTS: 60 injuries occurred in boys and 4 occurred in girls. There were 26 boys with significant injuries and no girls with significant injuries. The significant game injury rates per 1000 player hours were 50.9 for boys combined, 57.9 for boys' Peewee A, 42.7 for boys' Bantam A, 64.8 for boys' varsity high school, 44.8 for boys' Junior Gold, and 0 for girls' Peewee A and B. Cerebral concussion comprised 15% of boys' injuries. CONCLUSIONS: The significant injury rate for boys' tournament game play was 4-6 times higher than the season game injury rates in two previous season-long studies. In boys' games, 65% of "all" injuries and 77% of "significant" injuries were related to collisions. The girls' rules of play do not allow body checking, and there were no significant injuries in girls' games. The boys had high rates of cerebral concussion injury at all age levels. Minimizing the frequency and intensity of collisions in the boys' game may decrease the injury rates, especially in the tournament setting.
Factors that predict intercollegiate ice hockey injuries.
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Fair-play rules and injury reduction in ice hockey.
OBJECTIVE: To determine the rate, type, and severity of injuries incurred and penalties assessed during the qualifying fair-play (points for playing without excessive penalties) and championship "regular" rules (winner advances) portions of a 1994 Junior Gold ice hockey tournament. DESIGN: A prospective evaluation of injuries by certified athletic trainers at the tournament site. SETTING: A community-organized, 3-day, 31-game tournament in Minnesota. PARTICIPANTS: Two hundred seventy-three male players, younger than 20 years and in high school. MEASUREMENTS/MAIN RESULTS: Injuries were recorded by an on-site certified athletic trainer, and the penalties were tallied from the score sheets. The injury rates for the total number of injuries were 26.4 injuries per 1000 athlete exposures and 273.8 injuries per 1000 player hours. When only notable injuries (concussion, facial laceration, or moderate level of severity and above) were considered, the injury rates were 10 per 1000 athlete exposures and 103.9 per 1000 player hours. The ratio of notable fair-play to notable regular-rules injuries was 1:4.8. The number of penalties assessed per game averaged 7.1 penalties during fair-play rules and 13 penalties during the regular-rules competition. Penalties related to rough play and injury occurred four times more frequently during games with regular rules than those with fair-play rules. CONCLUSIONS: The fair-play concept can reduce injury rates, penalty rates, and severity of penalties and should be considered for ice hockey at all levels of play. The fair-play concept could be applied to other contact sports to reduce injury rates and rules infractions.
Risk for sudden cardiac death associated with marathon running.
OBJECTIVES: This analysis was performed to quantitatively assess the relative risks, associated with underlying cardiovascular disease, incurred in the course of intense competitive sports. BACKGROUND: Sudden cardiac death during athletic activities is a highly visible event, and controversy persists regarding the true risks associated with participation in sports. METHODS: The prevalence of sudden death was assessed in two systematically tabulated groups of endurance runners competing in the annual Marine Corps (1976 to 1994) and Twin Cities (1982 to 1994) marathons, held over a cumulative 30-year period. RESULTS: A total of 215,413 runners completed the races, and four exercise-related sudden deaths occurred, each due to unsuspected structural cardiovascular disease. Three deaths occurred during the race (after 15 to 24 miles [24 to 38.4 km]) and the other immediately after its completion. The ages were 19 to 58 years (average 37), and three were men. Three of the sudden deaths were due to atherosclerotic coronary artery disease (narrowing of two or three vessels) and one to anomalous origin of the left main coronary artery from the right sinus of Valsalva. None of the four runners had prior documentation of heart disease or experienced prodromal symptoms, and two had previously completed three marathon races each. The overall prevalence of sudden cardiac death during the marathon was only 0.002%, strikingly lower than for several other variables of risk for premature death calculated for the general U.S. population. CONCLUSIONS: Although highly trained athletes such as marathon runners may harbor underlying and potentially lethal cardiovascular disease, the risk for sudden cardiac death associated with such intense physical effort was exceedingly small (1 in 50,000) and as little as 1/100th of the annual overall risk associated with living, either with or without heart disease. The low risk for sudden death identified in long-distance runners from the general population suggests that routine screening for cardiovascular disease in such athletic populations may not be justifiable.
Whole-body cooling of hyperthermic runners: comparison of two field therapies.
Severe exercise-induced hyperthermia requires rapid cooling. Of the many cooling modalities available, there is disagreement over which is the most effective. The purpose of this field study was to compare two cooling therapies for hyperthermic distance runners who had completed an 11.5-km summer foot race. Twenty-one distance runners (mean [+/- SE] initial rectal temperature 41.2 +/- 0.2 degrees C) were treated either by ice water immersion (1 to 3 degrees C, n = 14) or by air exposure while wrapped in wet towels (24.4 degrees C ambient, n = 7). Ice water immersion versus air exposure resulted in significantly different (P < .005) pretherapy to posttherapy changes in rectal temperature (-3.0 +/- 0.3 v -1.4 +/- 0.3 degrees C) and mean cooling rate (0.20 +/- 0.02 v 0.11 +/- 0.02 degrees C/min). Ice water immersion cooled approximately twice as fast as air exposure. These data refute the theory that ice water immersion is an inefficient cooling modality.
The risk of heat stress in Atlanta '96.
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American College of Sports Medicine position stand. Heat and cold illnesses during distance running.
Many recreational and elite runners participate in distance races each year. When these events are conducted in hot or cold conditions, the risk of environmental illness increases. However, exertional hyperthermia, hypothermia, dehydration, and other related problems may be minimized with pre-event education and preparation. This position stand provides recommendations for the medical director and other race officials in the following areas: scheduling; organizing personnel, facilities, supplies, equipment, and communication; providing competitor education; measuring environmental stress; providing fluids; and avoiding potential legal liabilities. This document also describes the predisposing conditions, recognition, and treatment of the four most common environmental illnesses: heat exhaustion, heatstroke, hypothermia, and frostbite. The objectives of this position stand are: 1) To educate distance running event officials and participants about the most common forms of environmental illness including predisposing conditions, warning signs, susceptibility, and incidence reduction. 2) To advise race officials of their legal responsibilities and potential liability with regard to event safety and injury prevention. 3) To recommend that race officials consult local weather archives and plan events at times likely to be of low environmental stress to minimize detrimental effects on participants. 4) To encourage race officials to warn participants about environmental stress on race day and its implications for heat and cold illness. 5) To inform race officials of preventive actions that may reduce debilitation and environmental illness. 6) To describe the personnel, equipment, and supplies necessary to reduce and treat cases of collapse and environmental illness.
Children's ice hockey injuries.
OBJECTIVE: To determine the rate, type, and severity of injuries to child hockey players as well as assessing coaches', parents', and players' attitudes and knowledge of hockey. DESIGN: A prospective observation of a population's injuries using injury-reporting forms and surveys. SETTING: A community-organized hockey program in Minnesota. PARTICIPANTS: One hundred fifty boys, aged 9 through 15 years, who played ice hockey during the 1990-1991 winter season. MEASUREMENTS AND MAIN RESULTS: Injuries were reported by multiple observers, including coaches, managers, and trained independent observers at the time an injury occurred; coaches, parents, and players were surveyed regarding hockey injuries, knowledge, and attitudes. One in three players experienced an injury during the season. The most common injuries were contusions. Six of 100 players experienced injuries severe enough to require cessation of physical activities for 8 to 25 days or longer. Weight differences of 53 kg and height differences of 55 cm were reported between Bantam-aged players (13 through 15 years), and body contact, including legal checks, accounted for 86% of injuries during games. Illegal checks and violations were associated with 66% of injuries during games, yet only four penalties (14%) were assessed. In addition, one in three games in which an injury resulted was described as hostile and 15% of the injuries were considered intentional. CONCLUSIONS: Eliminating violence and body checking for prepubertal boys while emphasizing rule enforcement and good sportsmanship are recommended.
Return to training and competition after deep venous calf thrombosis.
A 25-yr-old female triathlete presented with 4 d of increasing left calf pain that started 1 d after an elective termination of pregnancy during the eighth week of gestation. She had been training with running, bicycling, and swimming but did not recall any injury to the calf muscle. Deep venous thrombosis of the calf and popliteal veins was diagnosed, and she was treated with intravenous heparin and oral warfarin anticoagulation. Her major concern was return to training and competition. A protocol was developed based on experience with less active patients and animal studies to allow a progressive return to training activities over 5 wk, followed by running in the sixth week. After release from the hospital, she accelerated the return-to-training protocol and progressed to running within 3 wk. She developed the post-phlebitic syndrome that resolved within 2 yr. The diagnosis and treatment of deep venous thrombosis are reviewed, with specific attention to the needs of athletic patients.
Malnutrition in a compulsive runner: a case conference.
A 28-yr-old, female marathon and "fitness" runner presented with leg swelling, fatigue, and loss of endurance. She was running an hour or more daily in addition to regular biking and swimming. She was an instructor in a fitness center. For 2 months prior to her leg swelling, she had increased fatigue and decreased exercise tolerance. She had been seen previously for a slow healing hamstring strain. She had not had a menstrual period for over 2 yr and had refused evaluation. She admitted to very low dietary intake, which she had always denied. She was worried about her body fat. She denied recent blood loss, diuretic or cathartic use, and induced vomiting. She appeared malnourished, pale, and older than her stated age. Her weight was 41.4 kg. Her blood pressure was 90/60, and her pulse was 100 per minute. She had pitting edema of the lower extremities to the knees. The diagnosis of anorexia nervosa was made and will be discussed.
Heat illness.
A 17-year-old girl collapsed during a field hockey practice on a hot August afternoon, apparently suffering from heat illness, which is responsible for about 5,000 deaths annually. A panel of experts explores this girl's case, discusses heat illness in general, and makes recommendations about diagnosis, prevention, and treatment.
Late treatment of paracetamol poisoning with mercaptamine.
Forty patients who had taken overdoses of paracetamol were treated with mercaptamine. Twenty-three patients given mercaptamine within 10 hours of poisoning had normal liver function tests at follow-up, and one could not be traced. In 16 patients mecraptamine was begun more than 10 hours after ingestion of paracetamol ("late" mercaptamine). Eight of these patients developed severe liver damage, which in six was moderate or severe before mercaptamine administration. Acute renal failure occurred in two patients; in one other renal function was temporarily severely impaired. At follow-up two patients were not available, and one admitted moribund had died soon after admission. The remaining 13 all had normal liver function tests. It is concluded that late mercaptamine is not dangerous and may prevent further liver damage.