Background and importance:
Spontaneous regression of herniated lumbar discs over a course of time is well documented in literature. But the concomitant relief of symptoms is not seen always. The reports of regression within 3 months are a few. Kim ES et al reported about the peroperative identification of regression of an extruded disc fragment, during microdiscectomy 2 months after the magnetic resonance imgaging(MRI).
A 58-year lady presented with backache, left leg pain, and weakness for 3 months. A magnetic resonance imaging ( MRI) scan of lumbosacral spine, taken three months back, showed L3-4 disc extrusion and canal stenosis and grade 1 listhesis at L5-S1. She had improvement with conservative treatment. But she had recurrence of symptoms 10 days back. Straight leg raising test was positive at 40 degree on left side. Dorsiflexion was grade 4 on left side. Sensations of touch and vibration were reduced in L4 dermatomal region.
A repeat MRI scan was done to plan surgery. The disc extrusion at L3-4 had shrunk, with the residual listhesis at L5-S1. She was given gabapentin, methylcobolamine, and physiotherapy. She improved over 1 week.
Spontaneous regression of herniated lumbar disc can occur within three months, without corresponding symptomatic relief. So it is better to do a repeat imaging before planning surgery for a patient with a prior diagnosis of disc herniation. Thus an unnecessary surgery can be avoided.