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This is a T2-weighted sagittal MRI of the lumbar spine for patient Iqbal Mir, 19/M (MRI 3485, dated May 20, 2026, Shafiee Drug Store MRI Unit / SDH Beerwah).
MRI Lumbar Spine — Findings & Interpretation
What I Can See
Vertebral Bodies (L1–S1 visible):
- Overall vertebral body heights appear maintained with no obvious compression fracture or endplate collapse.
- The vertebral marrow signal appears grossly normal on this T2 sequence.
Intervertebral Discs:
- The upper lumbar discs (L1–2, L2–3, L3–4) appear to have relatively preserved disc height and T2 signal (bright = hydrated/normal).
- L4–L5 and L5–S1 discs — there is notable reduced disc height and reduced T2 signal (dark/desiccated) compared to the upper levels, consistent with degenerative disc disease (disc desiccation).
- At the L5–S1 level, there is suggestion of a posterior disc bulge or herniation, with narrowing of the posterior disc space and potential encroachment on the thecal sac.
Spinal Canal / Thecal Sac:
- The lumbar lordosis is present but appears somewhat reduced (mild straightening).
- The posterior elements and facet joints show mild degenerative changes at the lower levels.
- The cauda equina filaments appear visible; there is some crowding at L4–L5 and L5–S1.
Conus Medullaris:
- Appears to terminate at an appropriate level (around L1–L2), within normal limits.
Impression (Radiological Summary)
| Level | Finding |
|---|---|
| L1–L3 | Discs appear normal in height and hydration |
| L4–L5 | Reduced disc height; early degenerative change |
| L5–S1 | Disc desiccation + posterior disc protrusion/herniation, possible thecal sac contact |
| Vertebral bodies | No fracture, no listhesis (no obvious spondylolisthesis) |
| Canal | No gross central canal stenosis, though lower levels show crowding |
Clinical Correlation
Given that the patient is 19 years old, degenerative changes at L4–L5 and L5–S1 are early for age and clinically significant. Common presentations with this pattern include:
- Low back pain, possibly radiating to buttock/leg (sciatica) if the L5 or S1 nerve root is compressed
- Radiculopathy if nerve root contact/compression is confirmed on axial cuts
⚠️ Important: This is a preliminary interpretation of a photograph of an MRI screen. A formal radiologist report is essential for clinical decision-making. Axial (cross-sectional) sequences are particularly important to assess the degree of disc herniation, nerve root compression, and canal stenosis accurately — those are not visible here.
Recommended Next Steps
- Formal radiological report from a qualified radiologist (if not yet done).
- Axial T2 sequences at L4–L5 and L5–S1 to assess nerve root compression.
- Neurological examination — check for motor/sensory deficits in L4, L5, S1 distributions.
- Conservative management first: physiotherapy, NSAIDs, activity modification — disc herniations in young patients have a good rate of spontaneous resolution (up to 2/3 within 12 weeks).
- If symptoms persist >6–12 weeks despite conservative care, or if there is progressive neurological deficit, consider surgical consultation.
— Grainger & Allison's Diagnostic Radiology
What specific nerve roots are affected at L5-S1?
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Nerve Roots Affected at L5–S1
The diagram below illustrates exactly which roots are at risk:
The key principle: a disc at level X–Y compresses the root numbered one level below (because that root is still traversing the canal at that disc level before exiting below).
The Two Roots Involved at L5–S1 — Depends on Herniation Type
| Herniation Type | Root Compressed | Frequency |
|---|---|---|
| Posterolateral (most common) | S1 | ~50% of all lumbar herniations |
| Far lateral / foraminal | L5 | Less common |
S1 Root Compression (Posterolateral L5–S1 disc — the typical pattern)
| Feature | Detail |
|---|---|
| Pain | Buttock → posterior thigh → posterior calf → heel and lateral foot (sole, 5th toe) |
| Weakness | Plantar flexion (gastrocnemius/soleus) — difficulty standing on tiptoe |
| Sensory loss | Lateral foot, sole, posterior calf |
| Reflex lost | Ankle jerk (Achilles reflex) — hallmark sign |
| Special test | Positive straight-leg raise (Lasègue sign) |
L5 Root Compression (Far-lateral L5–S1 disc)
| Feature | Detail |
|---|---|
| Pain | Hip → posterolateral thigh → lateral calf → dorsum of foot → 1st/2nd toes |
| Weakness | Dorsiflexion of foot and big toe (extensor hallucis longus) — foot drop |
| Sensory loss | Lateral calf, dorsum of foot, 1st–2nd web space |
| Reflex | Ankle jerk usually normal; knee jerk normal |
Quick Clinical Rule for Iqbal Mir (19/M)
Since the MRI shows a posterolateral protrusion at L5–S1 (the most common pattern), the S1 root is the primary suspect. Ask about:
- Loss of ankle jerk ✓
- Difficulty standing on tiptoe ✓
- Pain/numbness in the heel and outer sole ✓
If the herniation is more lateral (foraminal), the L5 root would be affected instead, giving foot drop and dorsal foot numbness.
Adams and Victor's Principles of Neurology, 12th Ed., Table 10-1 | Localization in Clinical Neurology, 8th Ed., p. 235
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