Neurogenic claudication secondary to vascular disease

Impaired somatosensation in patients with isolated proximal-without-distal exercise-related lower-limb ischemia

OBJECTIVES

Isolated proximal-without-distal (buttock but not calf) exercise-related lower-limb ischemia (IPI) might develop in the presence of arterial lesions impairing the blood flow supply toward the hypogastric vascular bed. In IPI, lower-limb sensory nerve dysfunction might occur from the sacral nerve plexus becoming ischemic during exercise. The purpose of this study was to compare patients with IPI with healthy controls for the presence of sensory nerve dysfunction, as assessed using somatosensory testing (SST).

METHODS

Seventeen nondiabetic patients with IPI and 17 age-matched and sex-matched healthy controls underwent SST of both the upper and lower limbs.

RESULTS

The upper-limb SST data did not differ between groups (P>0.05). In contrast, lower-limb testing showed that patients with IPI had impaired warm (43.4±2.7 vs. 40.5±4.9°C) and vibration (5.0±2.3 vs. 6.4±1.4 arbitrary units) detection thresholds compared with healthy controls (P≤0.05). Furthermore, lower-limb mechanical detection threshold and Neuropathy Symptom and Disability Scores tended to be higher in the patients (P≤0.10).

DISCUSSION

The SST data suggest that patients with IPI have abnormal functioning of Aβ-fiber and C-fiber inputs in their affected limb(s). These sensory abnormalities might contribute to the exercise-induced ischemic symptoms experienced by these patients.

Leriche's syndrome presenting as sciatica

Sciatica is a common cause of lower back pain and claudication; the true etiology is often misunderstood. We report a case of a 53-year-old man who presented with sciatica. Clinically, there was evidence of aortoiliac obstruction with the absence of femoral pulses and a vascular index of 0.4 at the ankle. An aortogram revealed a very tight irregular stenosis of the aortic bifurcation and bilateral proximal common iliac arteries. After resection of diseased aorta, an aortoiliac graft was inserted. The symptoms subsided. This case highlights the importance of performing a complete vascular evaluation in patients diagnosed with sciatica.

Systematic diagnostic approach to proximal-without-distal claudication in a vascular population

BACKGROUND

Very few observations of proximal-without-distal claudication have been reported in the literature. This is likely due to the use of questionnaires limiting vascular claudication to the calves and to the problems encountered in attributing unexplained "buttock" claudication to a vascular origin.

METHODS

During a 2 1/2-year period, we searched for proximal-without-distal exercise-related pain with the San Diego claudication questionnaire among some 2000 patients referred for lower limb arterial investigations. Of these patients, 97 presented no contraindication to treadmill testing and were investigated with exercise transcutaneous oxygen pressure (tcpO2). We used buttock tcpO2 (DROP index<-15 mm hg) to argue for the presence of ischemia on the corresponding side.

RESULTS

Ischemia consistent with symptoms was found in 61 patients, whereas pain on one or both sides without underlying ischemia was found in 36 patients, suggesting a non-arterial origin of the symptoms. More than half of the patients with proximal-without-distal claudication and underlying exercise-related ischemia had been suffering for more than 2 years before they were referred to the laboratory. Eleven of the patients were treated. The treatment was successful in all but one of them.

CONCLUSIONS

An important delay before diagnosis is frequently observed in proximal-without-distal claudication. TcpO2 is useful in attributing proximal exercise-related pain to a vascular origin. Given the number of detected and successfully treated patients in this small monocentric study, it is surprising that so few observations have been published to date, suggesting that proximal-without-distal arterial claudication is most likely an underestimated diagnosis.