Right Calf Claudication Revealing Leriche Syndrome Presenting as Right Sciatic Neuropathy
A 52-year-old male with a past history of hypertension and bony fusion of the thoracolumbar spine (from 11th thoracic to 2nd lumbar vertebrae) due to tuberculous spondylitis, was presented to the department of orthopedic surgery. He was a heavy smoker and complained of right foot pain, claudication in his right calf, impaired gait functions, and muscle wasting on the right lower limb, which had begun 7 months prior to the visit.\nMagnetic resonance imaging (MRI) of the thoracolumbar spine showed severe kyphotic curvature in the thoracolumbar spine, and central canal stenosis on the 10th and 11th thoracic vertebra level with a relatively well preserved lumbar spinal canal ().\nThe first impression of his attending surgeon was that he had spinal stenosis, related to severe thoracolumbar kyphosis. However, his symptoms were not well correlated to the MRI findings; and his condition did not improve, despite undergoing two weeks of medication. Subsequently, he took an electrophysiologic study at the department of neurology. The nerve conduction study revealed reduced amplitude of the right tibial and peroneal compound motor action potential, and the sural sensory nerve conduction study result was within the normal range (). Needle electromyography showed abnormal spontaneous activities in the right tibialis anterior, peroneus longus, short head of the biceps femoris, gastrocnemius, extensor digitorum brevis, and the abductor hallucis. On volition, the giant motor unit action potential was noted in the tibialis anterior (). These electrophysiologic findings were suggestive of partial right sciatic neuropathy. They concluded that the patient's foot pain and claudication were caused by sciatic neuropathy, combined with lumbar spinal stenosis, and maintained medication for neuropathic pain.\nTwo months later, he visited the department of rehabilitation medicine for an impairment rating and disability determination, and was still complaining of right foot pain and right leg claudication. We focused on the previously diagnosed non-traumatic right sciatic neuropathy noting his medical history; and performed an extended examination to reveal an undiscovered cause of neuropathy, or other possible causes of his symptoms. He described right leg intermittent claudication affecting the buttocks, and a burning ache radiating to the calves and foot. His claudication was exacerbated during walking and slightly relieved when resting. Upon physical examination, we were able to palpate diminished femoral and popliteal pulses on the right lower limb compared with the other side. On neurologic examination, the sensory test showed hypesthesia in the right lateral knee and foot, and sole of the foot. The motor power of the right lower limb was above grade four in all tested muscle groups, but was slightly weaker than the left side. Atrophy was also found in the right calf, anterior leg and foot muscle, and deep tendon reflexes were hypoactive in the right lower limb.\nComputed tomography (CT) angiography was performed to rule out the possibility that the symptoms were caused by ischemic disease. CT angiography of the lower extremities showed an occlusion of the infrarenal abdominal aorta, and bilateral common iliac and right external iliac arteries; and collateral circulations to both the internal iliac arteries and left external iliac artery were also observed. However, there were no significant findings that could cause sciatic neuropathy, such as mass lesions (). These findings were compatible with Leriche syndrome. Therefore, we concluded that our patient had Leriche syndrome causing ischemic injury of the right sciatic nerve.\nHe was referred to the department of surgery and underwent a bilateral axillo-femoral and femoro-femoral bypass graft. After the bypass surgery, his symptoms including claudication and right foot pain were relieved; but hypesthesia and motor weakness of the lower limb arising from sciatic neuropathy persisted at the time of the last follow-up visit, 8 months after the surgery.