An Unusual Case of Leg Pain in a Competitive Cyclist

Abstract

Cycling has become a popular recreational and competitive sport. The number of people participating in the sport is gradually increasing. Despite being a noncontact, low-impact sport, as many as 85% of athletes engaged in the sport will suffer from an overuse injury, with the lower limbs comprising the majority of these injuries. Up to 20% of all lower extremity overuse injuries in competitive cyclists are of a vascular source. A 39-year-old competitive cyclist had a 5-year history of thigh pain during cycling, preventing him from competing. The patient was eventually diagnosed with external iliac artery endofibrosis. After conservative treatment failed, the patient underwent corrective vascular surgery with complete resolution of his symptoms and return to competitive cycling by 1 year. Since its first description in 1985, there have been more than 60 articles addressing external iliac artery endofibrosis pathology.

Arterial endofibrosis in professional cyclists

“…First of all, the position: in order to obtain the maximal aerodynamic benefit, they force an hyperflexion of the hip joint that may alter the iliac artery anatomy inducing a chronic friction and stimulating the endofibrosis (9). A significant hypertrophy of the psoas muscle may worsen the mechanical stress: the muscle pinches the artery, which is often fixated to it by the fascia and its collateral branches, provoking a continuous arterial traction and a subsequent endofibrosis (9,10). This mechanism was particularly evident in our second case, where a thigh adhesion between artery and muscle was found.…”

Intravascular ultrasound imaging as a novel tool for the diagnosis of endofibrosis

“…Current literature suggests the etiology is most likely due to local mechanical factors such as the position of the athlete. Repetitive hyperflexion of the hip stimulates fibrotic changes within the vessel 3 . The repeated flexion may affect the adjacent fascia and prevent the iliac vessel from moving freely, rendering it susceptible to traumatic injury during exercise 2 .…”

“…The repeated flexion may affect the adjacent fascia and prevent the iliac vessel from moving freely, rendering it susceptible to traumatic injury during exercise 2 . Athletes may also develop hypertrophy of the psoas muscle over time, which stretches the iliac artery and creates mechanical stress that predisposes to fibrotic injury 3 . Although mechanical stress seems most likely, investigators have also suggested systemic factors for the cause of endofibrosis because most affected individuals display metabolic variations such as methionine metabolism abnormalities 6 …”

“…Diagnosis has previously been described by provocative duplex examinations and angiography, sometimes with pressure gradients obtained across the proposed lesion with vasodilators to mimic the exercise state 3 . Angiographic findings are generally subtle, and often, pharmacologically stimulating the high level of exercise needed to induce symptoms in these patients may not be possible.…”