Basketball can deform femur in young athletes, lead to arthritis

Proponents often maintain that basketball is a safer sport than rougher activities such as football or hockey. But a new study suggests that is not a slam dunk case.

As high school basketball players and younger travel-team players come in for sports physicals before the season’s start in late October in many states, pediatricians are likely to see more of a cam-type hip deformity that appears 10 times more often among men and boys who play elite-level basketball from an early age, according to a Swiss study.

A retrospective review of magnetic resonance images in 72 hips of 37 male basketball players aged between 9 and 25 years (mean age, 17.6 years) compared 76 hips of 38 age-matched controls who had not played competitive sports at a high level. Researchers reported that 15% of those who played high-level competitive basketball had painful hips and positive anterior impingement tests of physical examination. None of the controls reported hip pain.

Internal rotation of the hip averaged 30.1° among controls and 18.9° among the athletes. In addition, the maximum value of the alpha angle throughout the anterosuperior head segment was notably larger in the athletes at an average of 60.5° compared with 47.4° for the controls, and the differences became more pronounced after closure of the capital growth plate.

Evidence of a deformity in the femur that led to abnormal contact between the femur and the hip socket was found in basketball players who had participated in an elite-level team since the age of 8. Overall, the basketball players were 10 times more likely to have impaired hip function and an alpha angle greater than 55° in at least 1 measurement position.

Researchers concluded that basketball and other vigorous sports could lead to abnormal development of the head of the femur in young players, resulting in a deformed hip with impaired rotation and pain during movement. The deformity’s “expression in young adulthood may be triggered by environmental factors such as high-level sports activity during childhood and around the time of the closure of the femoral growth plate,” said lead researcher Klaus Siebenrock, MD.

The deformity leads to degeneration of the hip over time and is key factor in the increased incidence of osteoarthritis of the hip in serious athletes.

Other investigators have found that male athletes, particularly those who participate in running and jumping events in track and field and those who play soccer and handball, have greater risk of early osteoarthritis of the hip, noted Siebenrock.

Go back to the current issue of the eConsult.