RESUMO
We studied the historical changes of intervertebral disc displacement using magnetic resonance imaging. The phenomenon of the spontaneous regression of herniated discs is well known. The case of a 40-years-old male presenting with a large disc herniation at L5-S1, experiencing severe sciatic pain, and having the straight leg raising test positive at 25 degrees is presented. The extruded disc was documented by clinical examination. He was treated conservatively with epidural steroid injection (ESI), medication, physical therapy and self-exercise and reevaluated in 10 weeks later, 30 and 1 year. Large extruded disc can be treated successfully by physical therapy with ESI. However, the degeneration and the dehydration of disc result in decrease of disc height. Consequently, the regression of extruded disc might have been due to the resorption and the dehydration.