Hamstring tightness and sciatica in young patients with disc herniation.

We evaluated the nerve roots of the cauda equina by CT myelography in 36 patients aged from 11 to 19 years with lumbar disc herniation. On straight-leg-raising tests, six younger patients had isolated hamstring tightness with no sciatica (group A) and 30 had sciatic pain (group B). CT myelography showed that no patient in group A had associated nerve-root swelling, and that the roots were displaced posteriorly, but not compressed. In 21 of the group-B patients, swelling of the nerve roots was confirmed, with compression between the herniated disc and the superior articular process. Our findings suggest that hamstring tightness in these patients may be caused by a different mechanism from that which causes sciatic pain.