Ewing Sarcoma Causing Back and Leg Pain in 2 Patients

Abstract

A 69-year-old woman was referred by neurosurgery for evaluation of intractable left leg pain. The pain began 8 months earlier in the left low back, with radiation down the posterior thigh and lateral calf, and into the top of the left foot. The pain had a burning, aching quality and was more prominent at night. Treatments to date included restricting ankle motion in a walking boot for 4 weeks for presumed Achilles tendinopathy, physical therapy, spinal epidural injections, and oral agents including NSAIDs, gabapentin, and opioid analgesics. None of these treatments provided lasting benefit. Of note, the patient had a medical history of T-cell lymphoma 12 years previously. She had experienced 1 recurrence but had been in remission for 5 years. On review of systems, she mentioned marked ongoing fatigue, night pain, impaired sleep and appetite, weight loss, depression, and anxiety. Physical examination revealed a woman appearing of stated age in no apparent distress. Inspection demonstrated that her lower limbs were symmetric and without atrophy. Neurologic examination of the lower extremities was significant for decreased sensation over the left lateral calf, dorsum of the foot, and left medial malleolus. Tinel test at the left fibular head did not reproduce sensory symptoms. Strength of the lower limbs was normal and symmetric throughout, with the exception of left great toe extension, which was 4/5, and left knee flexion, which was 5–/5. Patellar and Achilles reflexes were 1 but symmetric. alpation of the inguinal region did not demonstrate inguinal lymphadenopathy. Vascular xamination showed symmetric distal lower limb pulses that were 2 , with good capillary efill. During the musculoskeletal examination, left hip external rotation reproduced familar buttock pain. There was marked tenderness over the left distal Achilles tendon and the orsum of the left foot. There was minimal lumbosacral tenderness. Lumbar spine range of otion, including flexion, side bending, and rotation, was unrestricted and painless; umbar extension, however, reproduced her familiar left gluteal pain. A prior outside umbar magnetic resonance image (MRI) demonstrated multilevel mild-moderate lumbar pondylosis most prominent at L3-L4 but no neural compression from disk herniation or entral or foraminal stenosis was present at any level. The differential diagnosis included left L4-L5 radiculitis, left L4-L5 lumbosacral plexpathy, left sciatic neuropathy, and a neuropathic tumor. We would expect sensory changes n the thigh with radiculopathy, which were not present. The distal distribution most closely pproximated the L5 nerve root, but L4 must be included for the abnormal medial malleolar ensation. An isolated left peroneal or saphenous neuropathy would not explain the roximal symptoms. Focal gluteal tenderness in conjunction with sensory changes rompted us to order an MRI. The sacrum (arrow), without bony involvement as seen on a 1 coronal oblique image, is demonstrated in Figure 1A. A coronal T1 image (Figure 1B)