WWW.SPORTEX-MEDICINE.COM

Figure 3: A typical triphasic wave form. Picture courtesy of Huntleigh Diagnostics Ltd, Cardiff, UK

ficiency will be revealed when the limb requires high volumes of blood ie. if a major arterial lesion exists on the AFP axis then peripheral pulses will be diminished immediately after exercise. An easily palpable or bounding pulse in the popliteal fossa may be indicative of popliteal aneurysm (the popliteal pulse is usual- ly difficult to palpate) and requires an opinion from a physician. Popliteal aneurysm has been reported in combination with advanced PAES.

Pulse auscultation Auscultation of pulses using a stethoscope has limited use. It is thought that in some cases of EIAE a bruit (abnormal low pitched whistling sound over the artery indicating turbulence) may exist on the affected side. Certainly a comparison of the affected and unaffected sides is worthwhile. Once again if a bruit exists then it will be more noticeable immediately after exercise or occasionally if the hip is flexed.The existence of a bruit is not conclusive by any means, as highly trained athletes have been noted as having inguinal bruits thought to be related to low resting heart rates (7).

Hand held Doppler ultrasound assessment Simple non-invasive clinical assessment of arterial circulation which allows accurate location evaluation of peripheral pulses. Probes are usually 4 or 8MHz depending on the artery to be assessed. Pulse quality is assessed as monophasic, biphasic or triphasic - triphasic being the optimum for normal healthy arteries (Fig.3). While the assessment technique is simple, training and practise are required for accurate application. The hand held Doppler may also be used to perform lower limb blood pressure measurements as part of ankle to brachial pressure index testing (see below) in combination with a sphygmomanometer (Fig.4).

Resting ankle to brachial pressure index (ABPI) This is a commonly used technique for the simple assessment of lower limb vascular insufficiency. The patient rests supine for 20 minutes prior to the test. It requires the use of a sphygmo- manometer, hand held Doppler or automatic BP monitor. Two mea- surements should be taken: ● Systolic brachial pressure (left and right) - using the highest value

● Systolic ankle pressure (Fig.5) Ankle to brachial pressure index

= Ankle systolic BP Brachial systolic BP

Maximal exercise testing In athletes it is uncommon to find abnormal resting ABPI results. Most complain of transient exercise related symptoms which are often only apparent under specific exercise conditions. Under these conditions maximal exercise testing to reproduce symptoms has been suggested as a valid non-invasive screening test for EILP (9).

12 SportEX

Figure 4: The use of a hand held Doppler sphygmomanometer to record the ankle systolic blood pressure. Picture courtesy of Huntleigh Diagnostics Ltd, Cardiff, UK

Figure 5: Cuff positioning for resting ABPI

Various protocols have been put forward involving treadmills and ergometer cycling. However, because there may be biomechanical factors involved in the aetiology of the presenting condition the exercise of choice should reflect this and achieve maximal blood flow through the suspected lesion. Therefore testing a rower or a cyclist on a treadmill may not replicate the conditions under which the symptoms occur and may provide false negative results. For that reason the test should be sport specific and should reproduce symp- toms as strongly as the patient experiences them during sport.

For EIAE in cyclists incremental ergometer cycling is the test of choice and the subject rides to volitional exhaustion or reproduc- tion of symptoms. At the end of the test the subject transfers immediately to the couch where ankle and brachial systolic pres- sures are repeated within the first minute post exercise. The lat- est research suggests that post exercise ABPI readings of <0.66 are considered indicative of an arterial lesion (9). A significant ABPI difference between left and right may also raise the suspi- cion of a lesion in unilateral cases.

0.90 - 1.0 normal

0.75 - 0.90 moderate disease 0.75 - 0.50 < 0.50

severe disease limb threatening disease Table 2: ABPI resting values

Key issues 1. Suspend disbelief - Young fit athletes may suffer vascular insufficiency which is known to present and be mistaken for neuromusculoskeletal syndromes

2. Accept negative findings - If your neuromusculoskeletal examination is thorough but negative - ‘think outside the box’ there may be another component to the pain syndrome

3. Be aware that vascular assessment may be entirely nor- mal at rest

4. Test the athlete to reproduction of symptoms (chronic cases only with stable symptoms) - they do it every day in training/competition and will be happy to demonstrate.

5. Make the maximal test sport specific - ie. reproduce the biomechanics of training or competition conditions

6. Rapid referral - if clinical testing indicates a high index of suspicion of a vascular issue. This is especially applicable if symptoms alter rapidly or the patient experiences reduced limb temperature or loss of pulses.

References 1. Mosimann R, Walder J, and Van Melle G. Stenotic intimal thickening of the external iliac artery: illness of the competition cyclists. Journal of Vascular Surgery 1985;19:258-63