Lumbar disc herniation (LDH) is a degenerative disease of the lumbar spine and a common cause of low back and leg pain 1) 2)
● Radiculopathy: pain and/or subjective sensory changes (numbness, tingling…) in the distribution of a nerve root dermatome, possibly accompanied by weakness and reflex changes of muscles innervated by that nerve root
● typical disc herniation → radiculopathy in the nerve exiting at the level below
● massive disc herniations can → cauda equina syndrome (a medical emergency). Typical symptoms: saddle anesthesia, urinary retention, LE weakness.
● most patients do as well with conservative treatment as with surgery, ∴ initial nonsurgical (conservative) treatment should be attempted for the vast majority
● surgery indications: cauda equina syndrome, progressive symptoms or neurologic deficits despite conservative treatment, or severe radicular pain > ≈ 6 weeks
Lumbar disc herniation (LDH) occurs owing to the inability of the posterior longitudinal ligament (PLL) to preserve the disc material within the intervertebral space. There is apparently no study that has investigated the histopathological changes occurring in both PLL and disc material in patients with LDH.
Kilitci et al. investigated and compared the histopathological changes occurring in PLL and disc material of the patients who underwent a surgical operation for LDH.
Pathology and neurosurgery departments of a tertiary Healthcare institution. The study included patients who underwent surgical operation for LDH from January 2018 to May 2019 and whose PLL and disc material was removed together, and had disc degeneration findings that were radiologically and histologically concordant.
PLL degeneration scores according to the histopathological findings, changes in disc materials according to the MRI findings, disc degeneration scores according to the histopathological findings.
Sample size: 50.
MRI and histological examinations showed fully degenerated black discs (Grade 2) in 12 patients, partially degenerated discs (Grade 1) in 29 patients, and fresh/acute discs (Grade 0) in 9 patients. The PLL showed grade 0 degeneration in 2 patients, grade 1 degeneration in 23 patients, and grade 2 degeneration in 25 patients. PLL degeneration grades were higher than the disc degeneration grades (P=.002).
Longitudinal ligament degeneration can play a significant role in the pathogenesis of LDH. This study represents the first to focus on the histopathological changes occurring in both the PLL and disc material in patients with LDH 3).
A prospective observational pre-post cohort study without a control group evaluated the effectiveness of PLDD in patients with lumbar disc protrusions. It contained herniations by assessing quantitative changes in the herniated disc area on axial and sagittal MR images.
A total of 58 patients with lumbar radiculopathy due to disc herniation underwent MRI two months after PLDD to evaluate changes in disc area. Axial and sagittal MR images with the greatest protrusion and neural compromise were analyzed, and patient pain severity, clinical outcomes, and satisfaction were recorded.
Results showed a statistically significant reduction in both axial and sagittal disc areas post-PLDD. The initial mean axial disc area of 0.51 cm2 (0.44-0.58) decreased to 0.29 cm2 (0.25-0.37), reflecting a median reduction of 35.9% (p < 0.0001). Similarly, the sagittal disc area decreased from a mean of 0.37 cm2 (0.33-0.43) to 0.19 cm2 (0.13-0.25), with a median reduction of 49.3% (p < 0.0001). All patients showed reductions in disc area, with a median reduction ratio of 52.7% (IQR: 45.2-56.2).
These findings suggest that PLDD is an effective option for reducing herniated disc size in carefully selected patients with contained disc herniations who have not responded to conservative treatment. Although not a substitute for open surgery, PLDD offers a statistically significant reduction in herniated disc size, making it a valuable therapeutic option for symptomatic contained lumbar disc herniation 4).
While the study provides interesting radiological data supporting PLDD in reducing disc herniation size, it suffers from critical methodological flaws:
No control group → cannot confirm that PLDD was the cause of improvement.
No functional correlation or long-term follow-up → limits clinical relevance.
Possible measurement and selection bias.
Final Appraisal: Level of Evidence: Low (Level IV, case series with pre-post design) Recommendation: Hypothesis-generating — further RCTs with sham controls, standardized outcome measures, and long-term follow-up are needed to support PLDD as an evidence-based alternative.