Three-Years Outcome of Microdiscectomy via Paramedian Approach for Lumbar Foraminal or Extraforaminal Disc Herniations in Elderly Patients over 65 Years Old

Transforaminal Unilateral Biportal Endoscopic Spinal Surgery for Extraforaminal Lumbar Disc Herniation: A Retrospective Observational Study

OBJECTIVE

Biportal endoscopic spinal surgery (BESS) is recommended as a safer and less destructive option for lumbar disc herniations. However, limited data exist on clinical outcomes for extraforaminal lumbar disc herniation (ELDH) surgery. This retrospective study presents our preliminary experience with transforaminal unilateral BESS for ELDH.

METHODS

Patients with lumbar radiculopathy refractory to conservative treatment, diagnosed with ELDH by magnetic resonance imaging, and treated with transforaminal unilateral BESS in 2021-2023 in 2 institutions in Taiwan were eligible for inclusion. Those with lumbar spondylolisthesis grade 2 or more with segmental instability, history of drug abuse or psychiatric diseases, or with a follow-up duration <1 year were excluded. Primary outcomes included visual analog scale for pain, assessed at 1 week, 1 month, 6 months, and 1 year using generalized estimating equations analysis; success and satisfaction of BESS graded by the Macnab criteria; and perioperative complications. Secondary outcomes were operative time and hospital length of stay.

RESULTS

Seventeen patients were included in the analysis, with a mean age of 65.8 years; 11 (64.7%) were males and 15 (88.2%) had no prior lumbar spine surgery. mean operative time was 107.9 minutes, and length of stay was 3.5 days. Graded by Macnab criteria, 16 (94.1%) of patients had good to excellent outcomes. Only 1 patient experienced complications. No recurrence/reoperation was observed. Generalized estimating equations analysis showed that postoperative visual analog scale scores decreased significantly at 1 week (adjusted Beta [aBeta] = -5.47, standard error: 0.29, P < 0.001), 1 month (aBeta = -5.82), 6 months (aBeta = -5.88), and 1 year (aBeta = -6.29).

CONCLUSIONS

Transforaminal unilateral BESS is an alternative and feasible method for treating ELDH, producing good surgical outcomes with few complications and sustaining pain improvement. Future studies with larger patient numbers and comparisons between BESS and other minimally invasive techniques for ELDH are warranted.

Morphological changes after open lumbar microdiscectomy at 2-year follow-up

BACKGROUND

It is known that a possible decrease in disc height (DH) and foraminal size after open lumbar microdiscectomy (OLM) may cause pain in the long term. However, there is still insufficient information about the short- or long-term pathoanatomical and morphological effects of microdiscectomy. For example, the exact temporal course of the change in DH is not well known.

OBJECTIVE

The purpose of this study was to examine morphological changes in DH and foramen dimensions after OLM.

METHODS

In patients who underwent OLM for single-level lumbar disc herniation, MRI scans were obtained before surgery, and at an average of two years after surgery. In addition to DH measurements, foraminal area (FA), foraminal height (FH), superior foraminal width (SFW), and inferior foraminal width (IFW), were measured bilaterally.

RESULTS

A postoperative increase in DH was observed at all vertebral levels, with an average of 5.5%. The mean right FHs were 15.3 mm and 15.7 mm before and after surgery, respectively (p= 0.062), while the left FHs were 14.8 mm and 15.8 mm before and after surgery (p= 0.271). The mean right SFW was 5.4 mm before surgery and 5.7 mm after surgery, while the mean right IFW ranged from 3.6 mm to 3.9 mm. The mean left SFW was 4.8 mm before surgery and 5.2 mm after surgery, while the mean left IFW ranged from 3.5 mm to 3.9 mm. Before surgery, the FAs were, on average, 77.1 mm2 and 75.6 mm2 on the right and left sides, respectively. At the 2-year follow-up, the mean FAs were 84.0 mm2 and 80.2 mm2 on the right and left sides, respectively.

CONCLUSIONS

Contrary to prevalent belief, in patients who underwent single-level unilateral OLM, we observed that there may be an increase rather than a decrease in DH or foramen size at the 2-year follow-up. Our findings need to be confirmed by studies with larger sample sizes and longer follow-ups.

Clinical signs, MRI findings and long-term outcomes of foraminal and far lateral thoracolumbar intervertebral disc herniations in dogs

BACKGROUND

As they have been seldomly described in the veterinary literature, the aims of this retrospective study were to describe the clinical presentation, MRI findings and long-term outcome after medical or surgical treatment of dogs presenting with foraminal and far lateral thoracolumbar intervertebral disc herniations.

METHODS

Retrospective multicentre study of dogs diagnosed with foraminal and far lateral thoracolumbar intervertebral disc herniations between 2009 and 2020 in seven referral hospitals.

RESULTS

Thirty-seven dogs were included. Dachshunds and mixed breeds were most affected. Median age at presentation and duration of clinical signs were 6 years and 14 days, respectively. Pain was the most frequent clinical finding (92%), particularly on spinal palpation and/or hip manipulation, followed by pelvic limb lameness (71%). Eighty-seven percent of herniations occurred at L5-L6 or L6-L7. A good to excellent outcome was seen in 95% of surgically and 90% of medically treated dogs.

CONCLUSION

Although much less frequently recognised than herniation affecting the vertebral canal, foraminal and far lateral thoracolumbar intervertebral disc herniations should be considered in the differential diagnosis list of chondrodystrophic dogs presenting with pain and pelvic limb lameness. Most dogs had a good to excellent outcome following medical or surgical treatment.

Factors Predicting Successful Outcome for Ozone Chemonucleolysis in Lumbar Disk Herniation

OBJECTIVES

The aim of this study was to retrospectively investigate factors predicting a successful outcome after ozone chemonucleolysis (OCN) in patients with radicular pain and poor response to conservative treatments.

METHODS

Univariable and multivariable logistic regression analysis was used to identify the predictors of good outcome after OCN. Good outcome was defined as 33% Oswestry Disability Index (ODI) reduction (model 1) or 13-point ODI improvement (model 2) at 1 month after OCN.

RESULTS

Two hundred seventy-three patients were analyzed. A significant pain reduction (pre-operative Numerical Rating Scale [NRS] 6.7 ± 1.5, postoperative NRS 2.6 ± 2.2, P < 0.0001) and ODI improvement (pre-operative ODI 39 ± 13.7, postoperative ODI 21.4 ± 13.8, P < 0.0001) was obtained 1 month after OCN. Pain duration (< 1 year), type of disk herniation based on Michigan State University classification (MSU), stages of disk degeneration revealed by discogram and absence of foraminal stenosis (bony or ligament flavum hypertrophy) appeared as predictors of successful outcome. Age, gender, previous spine surgery, level site of disk herniation, presence of uncontained lumbar disk herniation, and vertebral Modic changes were not statistically associated with the outcome. Both the models showed a good accuracy (model 1, area under the curve [AUC] = 0.84 ± 0.027, 95% confidence interval [CI] = 0.79 to 0.89; model 2, AUC = 0.86 ± 0.024, 95% CI = 0.81 to 0.91).

CONCLUSIONS

OCN is an effective treatment for radicular pain due to disk herniation. Pain duration (< 1 year), MSU disk herniation type (1A, 1B, 1C, 2A, and 2B), disk degeneration grade 2, and absence of foraminal stenosis are all associated with the successful outcome and should be carefully evaluated before OCN.

Microstructural changes are coincident with the improvement of clinical symptoms in surgically treated compressed nerve roots

Diffusion tensor imaging (DTI) has been widely used to visualize peripheral nerves, but the microstructure of compressed nerve roots can be assessed using DTI. However, there are no data regarding the association among microstructural changes evaluated using DTI, the symptoms assessed using the Oswestry Disability Index (ODI) and the duration of symptoms after surgery in patients with lumbar disc herniation (LDH). Thirty patients with unilateral radiculopathy were investigated using DTI. The changes in the mean fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) values as well as the correlation between these changes and the severity and duration of the clinical symptoms were investigated before and at least one month after surgery. The FA values were significantly increased after surgical treatment (p < 0.0001). Both the ADC and ODI values were noticeably decreased (p < 0.0001). A strong positive correlation between the preoperative and postoperative DTI parameters (p < 0.0001) as well as between the preoperative ODI and postoperative ODI/ODI changes (p < 0.0001) were found. In addition, there was a significant positive correlation between the changes in the DTI parameters and changes in the ODI (p < 0.0001). This preliminary study suggests it may be possible to use DTI to diagnose, quantitatively evaluate and follow-up patients with LDH.