Past, Present and Future of Arterial Endofibrosis in Athletes

Conservative Management and Postoperative Return to Sport in Endurance Athletes with Flow Limitations in the Iliac Arteries: A Scoping Review

BACKGROUND

Flow limitations in the iliac arteries (FLIA) is a sport-related vascular condition increasingly recognised as an occupational risk for professional cyclists and other endurance athletes. Surgical reconstruction is the definitive treatment for athletes wishing to continue competition. However, less information has been published regarding conservative management options and return-to-sport (RTS) guidelines.

OBJECTIVE

Our aim was to review the existing literature on conservative treatment of FLIA, identify knowledge gaps and propose an RTS framework for athletes returning to competition.

METHODS

A comprehensive literature review was performed using the Ovid-MEDLINE, PubMed, Embase and PEDro databases for publications relevant to conservative management of FLIA. A scoping review was conducted following PRISMA-ScR guidelines. Original, peer-reviewed publications in English describing conservative or postoperative management for athletes with FLIA were included. Additional grey literature and clinical expertise were consulted to inform RTS guidelines.

RESULTS

Overall, 62 studies were included in this review. In total, 11 categories of conservative modalities were extracted and presented qualitatively in terms of the information source (discussion or results statements) and perspective of the authors (positive, negative or mixed). We have proposed RTS guidelines covering pre-operative preparation and postoperative rehabilitation based on the available literature, clinical experience, and drawing from other areas of sports medicine research.

CONCLUSION

There is insufficient literature evaluating the effectiveness of conservative management options for FLIA to establish best practices. Considering the importance of RTS for competitive athletes, we proposed practical guidelines to help with clinician and patient decision making. Future consensus should be sought for RTS best practices.

Methods for epidemiological studies in competitive cycling: an extension of the IOC consensus statement on methods for recording and reporting of epidemiological data on injury and illness in sport 2020

In 2020, the IOC released a consensus statement that provides overall guidelines for the recording and reporting of epidemiological data on injury and illness in sport. Some aspects of this statement need to be further specified on a sport-by-sport basis. To extend the IOC consensus statement on methods for recording and reporting of epidemiological data on injury and illness in sports and to meet the sport-specific requirements of all cycling disciplines regulated by the Union Cycliste Internationale (UCI). A panel of 20 experts, all with experience in cycling or cycling medicine, participated in the drafting of this cycling-specific extension of the IOC consensus statement. In preparation, panel members were sent the IOC consensus statement, the first draft of this manuscript and a list of topics to be discussed. The expert panel met in July 2020 for a 1-day video conference to discuss the manuscript and specific topics. The final manuscript was developed in an iterative process involving all panel members. This paper extends the IOC consensus statement to provide cycling-specific recommendations on health problem definitions, mode of onset, injury mechanisms and circumstances, diagnosis classifications, exposure, study population characteristics and data collection methods. Recommendations apply to all UCI cycling disciplines, for both able-bodied cyclists and para-cyclists. The recommendations presented in this consensus statement will improve the consistency and accuracy of future epidemiological studies of injury and illness in cycling.

Arterial endofibrosis in endurance athletes: Prospective comparison of the diagnostic accuracy of intra-arterial digital subtraction angiography and computed tomography angiography

PURPOSE

To prospectively compare the diagnostic capabilities of computed tomography angiography (CTA) to those of digital subtraction angiography (DSA) in endurance athletes with suspicion of arterial endofibrosis.

MATERIALS AND METHODS

Forty-five athletes (39 men, 6 women; median age: 30 years, interquartile range: 23-42 years) prospectively underwent DSA and CTA without (n=5) or with (n=40) electrocardiogram gating. DSA was interpreted by a single expert (experience of 15 years). CTA was independently interpreted by three other readers (experience of 5-8 years). Readers assessed the presence and degree of stenoses on iliac and femoral arteries and the overall diagnosis (negative, uncertain, positive) of endofibrosis at the limb level. Sensitivities and specificities of DSA and CTA were estimated at the limb level using histological findings and long-term follow-up as reference, and compared using the McNemar test.

RESULTS

For diagnosing and quantifying stenoses, concordance between DSA and CTA was moderate-to-good for common and external iliac arteries, moderate for lateral circumflex arteries and poor-to-moderate for the other branches of the deep femoral artery. It was good for all readers for the overall diagnosis of endofibrosis. After long-term follow-up (median, 95 months; interquartile range: 7-109 months), DSA sensitivity and specificity were respectively 88.6% (39/44; 95% confidence interval [CI]: 76-95%) and 75% (24/32; 95% CI: 57.9-86.7%); CTA sensitivity and specificity were respectively 88.6% (39/44; 95% CI: 76-95%; P>0.99) and 84.4% (27/32; 95% CI: 68.2-93.1%; P=0.51), 86.3% (38/44; 95% CI: 73.3-93.6%; P>0.99) and 75% (24/32; 95% CI: 57.9-86.7%; P>0.99), and 84.1% (37/44; 95% CI: 70.6-92.1%; P=0.68) and 75% (24/32; 95% CI: 57.9-86.7%; P>0.99) for the three readers.

CONCLUSION

CTA shows performances similar to those of DSA in predicting the long-term diagnosis of endofibrosis in endurance athletes with suggestive symptoms.

Post-exercise ankle blood pressure and ankle to brachial index after heavy load bicycle exercise

The American Heart Association (AHA) recommendations for diagnosing peripheral artery disease (PAD) after exercise are a decrease >20% of ankle brachial index (ABI) or >30 mm Hg of ankle systolic blood pressure (ASBP) from resting values. We evaluated ABI and ASBP values during incremental maximal exercise in physically active and asymptomatic patients. Patients (n = 726) underwent incremental bicycle tests with pre- and post-exercise recording of all four limbs arterial pressures simultaneously. Univariate and multivariate analyses were performed to define the correlation between post-exercise ABI with various clinical factors, including age. Thereafter, the population was divided into groups of age: less than 40 (G < 40), from 40 to 44 (G40/44) from 45 to 49 (G45/49), from 50 to 54 (G50/54), from 55 to 59 (G55/59), from 60 to 64 (G60/64), and 65 and above (G ≥ 65) years. Results are mean ± SD. * is two-tailed P < .05 for ANOVA with Dunnett's post-hoc test from G40. Changes from rest in ASBP were -3 ± 22 (G < 40), -2 ± 20 (G40/44), 4 ± 22* (G45/49), 10 ± 25* (G50/54), 18 ± 21* (G55/59), 23 ± 27* (G60/64), and 16 ± 22* (G ≥ 65) mm Hg. Decreases from rest in ABI were 32 ± 9 (G < 40), 33 ± 9 (G40/44), 29 ± 8 (G45/49), 27 ± 10* (G50/54), 24 ± 7* (G55/59), 22 ± 12* (G60/64), and 21 ± 12* (G ≥ 65) % of resting ABI. Maximal incremental exercise results in ABI and ASBP changes are mostly dependent on age. The AHA limits for post-exercise ABI are inadequate following maximal incremental bicycle testing. Future studies detecting PAD in active patients should account for the effect of age.

Ankle to brachial systolic pressure index at rest increases with age in asymptomatic physically active participants

BACKGROUND

It is commonly acknowledged that the ability to use the ankle-brachial index (ABI), a reliable way to diagnose atherosclerosis, decreases with age in the general population. The aim of this study was to determine the relationship between resting ABI and age in different populations.

METHODS

674 physically active participants with (active high risk, ACT_HR) or without (active low risk, ACT_LR) cardiovascular risk factors or/and sedentary (SED) subjects, aged 20-70 years. Systolic arterial pressure was recorded at rest and simultaneously with automatic sphygmomanometers at the arms and ankles. ABI was calculated as the ratio of the lowest, highest or mean ankle pressure to the highest arm pressure.

RESULTS

Proportion of ABI_min<0.90 was 10.3% in SED_HR subjects versus 0.5% and 1.2%, respectively, in ACT_HR and ACT_LR groups. The averaged ABI value of each group was in the normal range in all groups (ABI>0.90) but was significantly lower in SED_HR compared with all active participants (p<0.001). Regression lines from ABI_mean versus age could lead to approximately +0.05 every 15 years of age in apparently healthy active participants (ACT_LR).

CONCLUSION

ABI at rest increases with the increase in age in the groups of low-risk asymptomatic middle-aged trained adults. The previously reported decrease in ABI with age is found only in SED_HR subjects, and is very likely to rely on the increased prevalence of asymptomatic arterial disease in this group. The increase of ABI with age is consistent with the 'physiological' stiffness observed in ageing arteries even in the absence of 'pathological' atherosclerotic lesions.

TRIAL REGISTRATION NUMBER

NIH clinicaltrial.gov: NCT01812343.

Exertional Leg Pain

Exertional leg pain is a common condition seen in runners and the general population. Given the broad differential diagnosis of this complaint, this article focuses on the incidence, anatomy, pathophysiology, clinical presentation, diagnostic evaluation, and management of common causes that include medial tibial stress syndrome, tibial bone stress injury, chronic exertional compartment syndrome, arterial endofibrosis, popliteal artery entrapment syndrome, and entrapment of the common peroneal, superficial peroneal, and saphenous nerves. Successful diagnosis of these conditions hinges on performing a thorough history and physical examination followed by proper diagnostic testing and appropriate management.

Bilateral Common Iliac Artery Endofibrosis in a Recreational Cyclist: Case Report and Review of the Literature

External iliac artery endofibrosis is a rare medical condition typically encountered in young endurance athletes, mainly cyclists. Iliac endofibrosis usually develops in the external iliac artery and is rarely seen in the common iliac or in common femoral arteries. We describe a unique case of a patient who was not a professional or high-endurance cyclist. The lesions in our case appeared to be bilateral in the common iliac arteries and were not limited to the external iliac artery as most commonly described. We present an overview of the literature regarding this medical condition.

Iliac artery endofibrosis in a middle-aged female long-distance runner

Exercise-induced iliac artery endofibrosis is a recently described abnormality of the external iliac artery that typically affects younger, healthy endurance athletes. Characteristic of the initially termed cyclist's iliac syndrome is lower limb pain during exercise with rapid recovery after exercise. This clinically complicated case describes an older female long-distance runner in whom an incorrect diagnosis of fibromuscular dysplasia was originally made when she presented with claudication and thrombosis of the right external iliac artery. A thrombectomy and bilateral balloon angioplasty were performed; however, her symptoms persisted. Four months later, she unexpectedly complained of dual calf claudication, a diagnosis of exercise-induced iliac artery endofibrosis was made, and a bilateral prosthetic graft bypass procedure was performed, which resulted in a good outcome.

An unusual case of leg pain in a competitive cyclist: a case report and review of the literature

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.

Vascular disorder in a competitive cyclist: a case report

The purpose of this case report was to alert the physical therapist (PT) to the possibility of vascular disorders in endurance athletes with apparent musculoskeletal symptoms. A 33-year-old female injured her knee in a fall and described a history of progressive unilateral lower extremity (LE) pain and weakness, especially with running and cycling. She received LE stretching and strengthening but her symptoms persisted, so she stopped all activity. When she became symptomatic with minimal exertion, she went to a neurologist, but electromyographic (EMG)/nerve conduction velocity (NCV) studies were normal. Eventually, she was referred for vascular studies, which confirmed a diagnosis of external iliac artery endofibrosis. The patient underwent a right common iliac to common femoral artery bypass graft approximately 3 years after onset of initial symptoms. She ran a 5K race 3 weeks after surgery and returned to cycling after 4 weeks. Endofibrosis of the external iliac artery is an uncommon disorder but is most frequently diagnosed in high-performance athletes, especially cyclists. Physical therapists who practice in orthopedic settings should be aware of vascular conditions that mimic musculoskeletal disorders in endurance athletes. Vascular consult or referral may be necessary if PT interventions are ineffective in treating athletes with exercise-induced LE pain and weakness.

Overuse injuries in professional road cyclists

BACKGROUND

Little epidemiological information exists on overuse injuries in elite road cyclists. Anecdotal reports indicate anterior knee pain and lower back pain may be common problems.

PURPOSE

This study was conducted to register overuse injuries among professional road cyclists with special focus on anterior knee and lower back pain.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

We attended training camps of 7 professional teams and interviewed 109 of 116 cyclists (94%) on overuse injuries they had experienced in the previous 12 months. Injuries that required attention from medical personnel or involved time loss from cycling were registered. Additional information on anterior knee pain and lower back pain was collected using specific questionnaires.

RESULTS

A total of 94 injuries were registered; 45% were in the lower back and 23% in the knee. Twenty-three time-loss injuries were registered-57% in the knee, 22% in the lower back, and 13% in the lower leg. Fifty-eight percent of all cyclists had experienced lower back pain in the previous 12 months, and 41% of all cyclists had sought medical attention for it. Thirty-six percent had experienced anterior knee pain and 19% had sought medical attention for it. Few cyclists had missed competitions because of pain in the lower back (6%) or anterior knee (9%).

CONCLUSION

Lower back pain and anterior knee pain were the most prevalent overuse injuries, with knee injuries most likely to cause time loss and lower back pain causing the highest rates of functional impairment and medical attention.

CLINICAL RELEVANCE

Future efforts to prevent overuse injuries in competitive cyclists should focus on lower back pain and anterior knee pain.

Endofibrosis in athletes: is a simple bedside exercise helpful or sufficient for the diagnosis?

OBJECTIVE

Ankle-to-brachial index (ABI) can be easily performed by all physicians. The Ruffier-Dickson (RD) test is an easy procedure to attain moderate exercise at the bedside for physicians who do not have an ergometer.

DESIGN

Retrospective analysis.

SETTING

Tertiary care, institutional practice.

PATIENTS

Fifty-three asymptomatic athletes and 22 patients suffering from unilateral pain due to histologically proven exercise-induced arterial endofibrosis (EIAE).

INTERVENTION

Brachial and ankle systolic blood pressures were measured in the supine position on the suspected leg in EIAE or left leg in controls, at rest (rest) and at the first minute of the recovery from incremental maximal cycle ergometer exercise (maxCE) and Ruffier-Dickson (RD) exercise tests.

MAIN OUTCOME MEASURES

Comparison of ABI(rest), ABI(maxCE), and ABI(RD) in discriminating patients from normal subjects, using receiver operating characteristics (ROC) curves.

RESULTS

Area (+/-SE of area) of ROC curve was 0.76 +/- 0.06 for ABI(rest), 0.83 +/- 0.05 for ABI(RD) (nonsignificant from rest), and 0.99 +/- 0.01 for ABI(maxCE) (P < 0.01 from ABI(RD) and P < 0.001 from ABI(rest)). An ABI(maxCE) below 0.48 was 100% specific and 80% sensitive for EIAE. For the RD test, a 100% negative predictive value was only attained for postexercise ABI values higher than 0.92.

CONCLUSION

ABI after maximal cycle ergometer exercise is more accurate than ABI after an RD test to search for unilateral EIAE in athletes.

Simultaneous Arterial Pressure Recordings Improve the Detection of Endofibrosis

PURPOSE

Exercise improves the diagnostic performance of ankle-to-brachial index (ABI) in the detection of exercise-induced arterial endofibrosis (EIAE). Pressure values for all four limbs are required to calculate ABI, but rapid systemic pressure changes occur during the recovery period from exercise. We checked whether after exercise, ABI calculated from simultaneous measurements was better than from consecutive measurements for differentiating athletes with EIAE from normal athletes.

METHODS

We studied 42 normal athletes and 42 athletes suffering from unilateral pain caused by histologically proven EIAE. Bilateral brachial and ankle (ASBP) systolic blood pressure levels were simultaneously measured in the supine position at rest and every minute during the first 4 min of the recovery from incremental maximal exercise. Using receiver operating characteristics curves (ROC), we compared the diagnostic performance of single-leg ASBP and ABI values and between-leg ASBP (DeltaASBP) and ABI (DeltaABI) differences, calculated from simultaneous (simu) versus consecutive (cons) measurements, to discriminate athletes with EIAE from normal athletes.

RESULTS

For single-leg postexercise values, ROC curve area was significantly higher for ABIsimu compared with ASBPsimu (P < 0.05, r = 0.91) and ASBPrand (P < 0.05, r = 0.68). Areas (+/- SE of area) of the ROC curves for postexercise Delta ASBPsimu and Delta ABIsimu were 0.97 +/- 0.01 and 0.97 +/- 0.02, respectively, and were higher than areas for postexercise Delta ASBP and Delta ABI calculated from consecutive and random measurements (P < 0.01). Accuracy for postexercise Delta ASBPsimu and Delta ABIsimu in discriminating EIAE from normal athletes was 93% [95% CI; 85-97], with a cutoff point of 22 mm Hg and 0.10, respectively.

CONCLUSION

Delta ASBP and/or Delta ABI calculated from simultaneous pressure measurements should be recommended when searching for unilateral EIAE. Whether this result is applicable in the detection of early atherosclerotic lesions in sedentary subjects requires future investigation.

Magnetic resonance angiography of abdominal and lower extremity vasculature

Magnetic resonance angiography (MRA) has evolved over the past years from an experimental imaging modality to a technique that is now widely applied in clinical practice. This article reviews the fundamentals of the different magnetic resonance angiographic techniques and how they can be applied for abdominal and peripheral arterial imaging. Currently, contrast-enhanced magnetic resonance angiography (CE-MRA), whereby a luminogram is obtained during initial arterial passage of contrast material, is the most widely used technique. With current hardware and software, high-spatial resolution images of the abdominal aorta and proximal visceral branches can be obtained that are equivalent to intra-arterial digital subtraction angiography (IA-DSA). High-quality imaging of the renal arteries demands isotropic voxels and reformations orthogonal to the vessel axis for evaluation. Contrast-enhanced magnetic resonance angiography of the peripheral vascular tree is now a highly accurate technique and has replaced diagnostic intra-arterial digital subtraction angiography and duplex ultrasonography in many hospitals.

The physiological response of ankle systolic blood pressure and ankle to brachial index after maximal exercise in athletes is dependent on age

The development of sports activities in the over forties has increased the number of middle-aged patients performing heavy-load exercise. The normal response of ankle systolic blood pressure (ASBP) and ankle to brachial index (ABI) to intense exercise is known in young athletes, but little is known for other age groups. Three groups of 21 athletes: <20 (G1), 20-40 (G2), and >40 (G3) years old, respectively, were studied. ASBP and brachial systolic blood pressure (BSBP) were measured simultaneously before and after an incremental maximal cycle ergometer test. Rest ABI was higher in G3 compared to G1 (P<0.001: ANOVA, Bonferroni). Compared to respective resting values, BSBP, at 1 min of recovery, was increased for the three groups of age (P<0.001) whereas ASBP was unchanged for G1 and G2, and significantly increased for G3 (P<0.001). ASBP was significantly higher in G3 than in G1 and G2, ABI was lower in G1 and G2 compared to G3: 0.70+/-0.11, 0.76+/-0.09 and 0.91+/-0.14, respectively. This age-related ABI increase is consistent with the impaired vasodilator capacity observed in aging normal subjects but not with the decrease observed in ABI resting values in epidemiological studies. ABI is higher in older than in younger athletes at rest and after exercise. In aging athletes, aiming to detect mild to moderate arterial lesions, it is likely that normal limits defined in young athletes are not valid.

Frequency of the C34T mutation of the AMPD1 gene in world-class endurance athletes: does this mutation impair performance?

The C34T mutation in the gene encoding for the skeletal muscle-specific isoform of AMP deaminase (AMPD1) is a common mutation among Caucasians (i.e., one of five individuals) that can impair exercise capacity. The purpose of this study was twofold. First, we determined the frequency distribution of the C34T mutation in a group of top-level Caucasian (Spanish) male endurance athletes (cyclists and runners, n = 104). This group was compared with randomly selected Caucasian (Spanish) healthy (asymptomatic) nonathletes (n = 100). The second aim of this study was to compare common laboratory indexes of endurance performance (maximal oxygen uptake or ventilatory thresholds) within the group of athletes depending on their C34T AMPD1 genotype. The frequency of the mutant T allele was lower (P < 0.05) in the group of athletes (4.3%) compared with controls (8.5%). On the other hand, indexes of endurance performance did not differ (P > 0.05) between athlete carriers or noncarriers of the C34T mutation (e.g., maximal oxygen uptake 72.3 +/- 4.6 vs. 73.5 +/- 5.9 ml.kg(-1).min(-1), respectively). In conclusion, although the frequency distribution of the mutant T allele of the AMPD1 genotype is lower in Caucasian elite endurance athletes than in controls, the C34T mutation does not significantly impair endurance performance once the elite-level status has been reached in sports.