A report of short term spontaneous regression of herniated lumbar disc


 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. 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. She was given gabapentin, methylcobolamine, and physiotherapy. She improved over 1 week. Spontaneous regression of herniated lumbar discs over a course of time is 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). 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.

Spontaneous regression of herniated lumbar discs over a course of time is 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 identi cation of regression of an extruded disc fragment, during microdiscectomy 2 months after the magnetic resonance imgaging(MRI). 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.
Sir/madam, A 58-year lady presented with backache for 3 months, radiating to left leg, and weakness of left foot. She had severe pain 3 months back. A magnetic resonance imaging ( MRI) scan of lumbosacral spine was taken at that time. It showed L3-4 disc extrusion and canal stenosis and grade 1listhesis at L5-S1 (Fig. 1).
Surgery was advised at that time. But the patient opted conservative treatment. She had signi cant improvement in symptoms.
But she had recurrence of symptoms 10 days back. Straight leg raising test was positive at 40 degree on left side. Dorsi exion 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 (Fig. 2). She was given another trial of conservative treatment with gabapentin, methylcobolamine, and physiotherapy. She improved over 1 week in pain, power, and sensation. weeks 2 . But they noted that the patients continued to be symptomatic and even with de cits in spite of radiological improvement. Spontaneous regression was more common in sequestrated fragments than subligamentous disc herniations. Chiu et al. found that the rate of complete resolution of disc herniation was 43% for sequestrated discs and 15% for extruded discs 3 . The mechanisms behind the regression are dehydration, shrinkage, retraction, and resorption by in ammation 4 . Phagocytosis by macrophages has been observed.
But the reports of spontaneous regression within a short term are few. Kim SG et al. described two male patients with clinical and radiological regression of lumbar discs in 3 months 5 . Albayraket al. published a report of regression of L5-S1 discsequestrationof a 32-year-old man in 14 days 6 . Kim ES et al. reported about a 58-year-old woman with a large L2-3 disc extrusion 7 . She underwent microdiscectomy after 2 months. But the expected disc fragment was not found. Immediate MRI showed the absence of the fragment. But in our case, it was detected prior to surgery with a repeat MRI. So an unwanted surgery was avoided. The probable mechanism of shrinkage may be either dehydration or resorption by in ammation, since the axial T2-weighted image shows a hypointense wrinkled fragment (Fig. 2c.). The knowledge of shrinkage of the extrusion helped in improvement of her symptoms, since psychological factors seem to play a major role in the outcome of low back pain as in the literature 8 .

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Compliance with Ethical Standards: Disclosure of potential Con icts of interest-Nothing to be disclosed.