Right L5-S1 paramedian disc protrusion with intraforaminal extrinsecation and associated signs of a previous left laminectomy. L4-L5 median disc protrusion with degeneration of right joint faces; channel at borderline limits in terms of size at L3-L4.
- MRI of lumbosacral vertebral column shows no evident structural or signal abnormalities found in examined skeletal segments.
Right convex scoliotic attitude of spinal column with fulcrum at L4-S1.
Signs of previous left laminectomy surgery at L5-S1.
Presence of left median and lateral herniated disc L4-L5, which is compressing the left ventrolateral face of the dural sac.
Vertebral channel at borderline size limits at L3-L4 due to presence of articular hypertrophy; anterior epidural space and conjugate foramen are within normal limits. No evident signs of pathological significance of the medullary cone.
Conclusions:
Presence of L4-L5 left median and lateral herniated disc with signs of previous surgery L5-S1 left and a reduction in size of the vertebral channel at L3-L4.
The patient was presented to me through radiographic studies (incomplete MR studies) without clinical information. Discussing such a case is extremely difficult because the mainstay of treatment is the clinical presentation and not radiological findings.
Given this case study, I can make the following assumptions:
1. This patient was operated on in the past at the L5-S1 disc.
2. The patient may suffer from lower back pain, Lt. radicular pain or both.
3. Surgery was offered to the patient.
MR scans present signs of degeneration in L4-5 and L5-S1 discs and less significantly in L3-4 level. There is mild degenerative scoliosis.
A second set of radiograms presents a sagital view of the lumbar spine with L3-4 bulge, L4-5 herniation with secondary narrowing of the canal and of disc space in L5-S1 level. Axial views show central and left disc herniation at L4-5 level, swelling of L4 root on the left and some narrowing of the canal at L5-S1 level.
I'll try to answer the questions:
1. Indications for surgery: In the case of intractable radicular pain originating at L4-5 disc and failure of conservative treatment (medications, epidural steroids etc,) laminectomy and discectomy are feasible.
2. If back pain is a significant part of the patient's complaints,
fusion must be considered. From MR images it seems that L3-S1 are affected, but I would prefer to have discographies of L2-3, L3-4 and L4-5 in order to identify the pain generation and investigate the L2-3 disc. If the patient is a smoker, I would be reluctant to fuse her vertebrae, because it is well known that a significant portion of these patients develop pseudoarthrosis leading to failure.
3. If the patient selection is adequate, we anticipate good surgical results. If only discectomy is chosen, the patient must be aware that the aim of the surgery is the radicular pain only and that there is up to 10% recurrence rate. The success rate following fusion is about 85%, while in smokers failure may be up to 40%.
4. Alternative treatments should be considered before deciding on surgery. Aside from those mentioned earlier, in cases of mechanical back pain one must consider treatment by radiofrequency ablation of the medial branches of the dorsal roots of the lower lumbar spine. Other treatments such as spinal cord stimulators are reserved for more advanced cases.