Background
Spinal abnormalities are more common in athletes than in non-athletes in the general population. Any spinal injury pattern can be observed in athletes who are subjected to trauma. Athletes are susceptible to degenerative disc changes at an early age because of the repetitive loading activities involved in sports.
Back pain is second only to the common cold as a cause of lost time from work and results in more lost productivity than any other medical condition. It has been estimated to result in 175.8 million days of restricted activity annually in the United States, and at any given time, 2.4 million Americans are disabled secondary to low back pain. Of these 2.4 million Americans, one half are chronically disabled. Data from the National Ambulatory Medical Care Survey from 1989-1990 revealed that there were almost 15 million office visits for low back pain, ranking this as the fifth reason for all physician visits.
In most industrialized nations, the lifetime prevalence of back pain exceeds 70%, and in the United States, a 15-20% 1-year prevalence rate has been estimated.
In 1990, 400,000 industrial low back injuries resulting in disability occurred in the United States. In 1985, a prospective Swedish study of adults aged 20-65 years conducted over an 18-month period reported over 7,500 work absences related to acute low back pain. Of these episodes, 57% of workers recovered within 1 week, 90% in 6 weeks, and 95% after 12 weeks. In 1987, Deyo reported a slower recovery rate in the United States, with only 33.2% of patients recovering in less than 1 month, 33% recovering in 1-5 months, and 32.7% taking longer than 6 months to recover. Finally, recurrence rates from 60-85% have been reported during the first 2 years following an acute back injury.
Frymoyer reported that 40% of patients experience leg pain in association with back pain; a much lower percentage reported numbness and weakness; and only 1% of adult respondents in the United States reported symptoms indicative of true sciatica. Herniated discs occur primarily in the second through the fifth decades of life and have a slight male preponderance. The L4-5 disc has been shown to be the most commonly herniated disc, resulting an L5 radiculopathy. The L5-S1 disc is a close second in frequency of herniation. Translating the frequency of back pain into economic terms emphasizes the magnitude of the problem. Lower back injuries account for approximately 22% of compensable workplace injuries, but they account for 31% of compensation payments. In the United States, the direct costs of spinal disorders were estimated to be in excess of $23 billion during 1990.This represented an increase of nearly 47% over the estimated costs in 1984.