Indirect Decompression Through Oblique Lateral Interbody Fusion for Revision Surgery After Lumbar Decompression

Oblique Lateral Endoscopic Decompression and Interbody Fusion for Severe Lumbar Spinal Stenosis: Technical Note and Preliminary Results

OBJECTIVE

Adequacy of decompression for oblique lateral interbody fusion (OLIF) is a real concern in patients with severe lumbar spinal stenosis (LSS). With this in mind, we combined OLIF with spinal endoscopic technique to achieve a solid fusion and an adequate decompression after one operation.

METHODS

This is a technical note. The theoretical basis and operation process of this technique were introduced, and consecutive cases were retrospectively collected. Consecutive patients diagnosed with monosegmental severe LSS (L4/5) and underwent oblique lateral endoscopic decompression and interbody fusion (OLEDIF) from January 2018 to February 2020 were retrospectively collected. Clinical outcomes were assessed by claudication distance, Visual Analog Scale (VAS), and Oswestry Disability Index (ODI) scores. Secondary indicators included operation time, operative blood loss, and postoperative complications.

RESULTS

Ten patients were selected for the OLEDIF procedure. They were five women and five men ranging in age from 49 to 75 years (mean age of 63.9 years) and in BMI from 25.4 to 30.2 kg/m² (mean BMI of 27.5 kg/m² ). The preoperative claudication distance was 160.00 ± 68.96 m (range 70-250 m), which was significantly extended on the 3-month and 1-year follow-up (1020.00 ± 407.70 m and 1040.00 ± 416.87 m, respectively). The preoperative VAS score of back pain and radiating leg pain was 5.50 ± 0.97 (range 4-7) and 6.40 ± 0.97 (range 5-8). The score on postoperative month 3 was 1.60 ± 0.52 (range 1-2) and 1.20 ± 0.79 (range 0-2), and the 1-year follow-up score was 1.90 ± 0.74 (range 1-3) and 1.60 ± 0.70 (range 1-3), respectively. The preoperative ODI was 72.23 ± 6.30 (range 64.4-82.2), the 3-month follow-up ODI was 31.12 ± 4.20 (range 24.4-35.6), and the 1-year follow-up ODI was 29.33 ± 5.92 (range 20.0-37.8). Compared with the transforaminal lumbar interbody fusion (TLIF) in the literature, the operation time was not prolonged (189.3 ± 32.5 min vs. 214.9 ± 60.0 min) but the amount of blood loss decreased significantly (113.3 ± 26.7 ml vs. 366.8 ± 298.2 ml). No complications were found except one case presented with dysesthesia of the left leg. Imaging results showed good fusion without cage subsidence during 1-year follow-up.

CONCLUSION

OLEDIF can achieve complete ventral decompression of the spinal canal and solid fusion of the lumbar spine at one time. It is an effective minimally invasive technique for the treatment of monosegmental severe LSS, which is promising and worthy of further clinical practice.

Percutaneous Intervertebral-Vacuum Polymethylmethacrylate Injection for Foraminal Stenosis with Degenerative Lumbar Scoliosis

BACKGROUND

Percutaneous intervertebral-vacuum polymethylmethacrylate injection (PIPI) is a minimally invasive procedure for low back pain in elderly patients with degenerative lumbar scoliosis (DLS). Patients with DLS often have radiculopathy as a result of foraminal stenosis in addition to low back pain. The purpose of this study was to evaluate the clinical and radiologic results of PIPI for foraminal stenosis with radiculopathy in elderly patients with DLS.

METHODS

We included patients with de novo DLS aged 65 years or older who underwent PIPI. The presence of an intervertebral vacuum on computed tomography and bone marrow edema on magnetic resonance imaging was required for inclusion. The intersegmental radiologic parameters on plain radiographs and computed tomography and the extent of bone marrow edema on magnetic resonance imaging were measured. The clinical outcomes were evaluated using the visual analog scale (VAS) and Oswestry Disability Index (ODI).

RESULTS

We enrolled 40 patients with DLS who underwent PIPI. There were 16 men and 24 women, and the mean age was 79.0 ± 6.3 years. The mean foraminal height and extent of bone marrow edema showed a significant increase and reduction, respectively, after PIPI (P < 0.05). VAS score for radiculopathy and ODI significantly improved after PIPI (P < 0.01). The minimum clinically important differences in VAS score for radiculopathy and ODI at the final follow-up were 73.9% and 63.6%, respectively.

CONCLUSIONS

PIPI is a minimally invasive procedure not only for low back pain but also for radiculopathy in elderly patients with DLS. It leads to intervertebral stabilization and indirect decompression of the foramen.

Assessment of the psoas muscle changes following the oblique lateral interbody fusion (OLIF) approach: A prospective observational study

Background

Traditional open posterior fusion techniques involve stripping of the posterior paraspinal muscles with protracted retraction, which can lead to ischemia and denervation. This may result in poor clinical outcomes despite a well-performed surgery. Oblique lumbar interbody fusion (OLIF) is a minimally invasive modified retroperitoneal anterior approach in the corridor between the psoas major (PM) and great vessels. The purpose of this research was to study changes in psoas properties and clinical outcomes in terms of the loss of hip flexion in patients undergoing OLIF surgery.

Methods

Patients with lumbar pathologies who underwent instrumented OLIF at our center were included. These patients were examined clinically at baseline and 6 months postoperatively. The Oswestry disability index (ODI) and visual analog scale (VAS) scores for back pain and leg pain were noted. Magnetic resonance imaging (MRI) scans were obtained preoperatively and postoperatively (minimum 6 months) to compare the cross-sectional areas (CSAs) of the PM.

Results

In total, 17 patients (male: female = 8:9) with a mean age of 46.06 ± 10.49 years were included. The operation time was 154.94 ± 32.33 min, estimated blood loss was 190 ± 56 mL, and mean CSAs of the right and left psoas were, respectively, 9.94 ± 3.19 and 10.65 ± 3.74 cm2 preoperatively and 10.00 ± 3.06 and 8.53 ± 2.81 cm2 at follow-up. Qualitative measurements revealed that muscle atrophy on the left side (approach side) was 19.12% ± 3.14% and fatty degeneration had occurred in 13 of 17 (76.5%) patients. Postoperatively, all patients had significant improvement in the VAS (back and leg) and ODI scores. Furthermore, 3 of 17 (17.6%) patients had mild hip weakness (4/5) on the left side immediately postoperatively, but it resolved in 6 months. Moreover, 2 of 17 (11.8%) patients complained of paraesthesia.

Conclusion

OLIF does cause injury to the PM but it is clinically insignificant according to MRI scans and clinical evaluations.

Which factor can predict the effect of indirect decompression using oblique lumbar interbody fusion?

The aim of this study was to investigate the association between various factors of indirect decompression. Previous studies have demonstrated the effectiveness of indirect decompression. There is no consensus regarding the predictive factors for indirect decompression. Facet joint gap (FJG) and bulging disc thickness (BDT) have never been considered as factors in other studies. We retrospectively reviewed 62 patients who underwent OLIF L4/5 between April 2018 and September 2020. The relationships between cross-sectional area (CSA) change, CSA change ratio, spinal stenosis grade, and various factors were studied. Various factors related to indirect decompression, such as ligament flavum thickness (LFT), foraminal area (FA), disc height (DH), bulging disc thickness(BDT), and facet joint gap (FJG), were measured. CSA increased from 69.72 mm2 preoperatively to 115.95 mm2 postoperatively (P < .001). BDT decreased from 4.97 mm preoperatively to 2.56 mm postoperatively (P < .001). FJG (Right) increased from 2.99 mm preoperatively to 4.38 mm postoperatively (P < .001). FJG (Left) increased from 2.95 mm preoperatively to 4.52 mm postoperatively (P < .001). The improvement of spinal stenosis grade was as follows: 1 point up group, 38 patients; 2 point up groups, 19 patients; and 3 point up groups, 3 patients. The correlation factors were prespinal stenosis grade (0.723, P < .00), CSA change (0.490, P < .00), and FJG change ratio (left, 0.336, P < .008). FJG showed statistical significance with indirect decompression. Indirect decompression principles might be utilized in patients with severe spinal canal stenosis (even grade 4).

Pearls and Pitfalls of Oblique Lateral Interbody Fusion: A Comprehensive Narrative Review

Lumbar degenerative disease is a common problem in an aging society. Oblique lateral interbody fusion (OLIF) is a minimally invasive surgical (MIS) technique that utilizes a retroperitoneal antepsoas corridor to treat lumbar degenerative disease. OLIF has theoretical advantages over other lumbar fusion techniques, such as a lower risk of lumbar plexus injury than direct lateral interbody fusion (DLIF). Previous studies have reported favorable clinical and radiological outcomes of OLIF in various lumbar degenerative diseases. The use of OLIF is increasing, and evidence on OLIF is growing in the literature. The indications for OLIF are also expanding with the help of recent technical developments, including stereotactic navigation systems and robotics. In this review, we present current evidence on OLIF for the treatment of lumbar degenerative disease, focusing on the expansion of surgical indications and recent advancements in the OLIF procedure.

Incidence of major and minor vascular injuries during lateral access lumbar interbody fusion procedures: a retrospective comparative study and systematic literature review

During lateral lumbar fusion, the trajectory of implant insertion approaches the great vessels anteriorly and the segmental arteries posteriorly, which carries the risk of vascular complications. We aimed to analyze vascular injuries for potential differences between oblique lateral interbody fusion (OLIF) and lateral lumbar interbody fusion (LLIF) procedures at our institution. This was coupled with a systematic literature review of vascular complications associated with lateral lumbar fusions. A retrospective chart review was completed to identify consecutive patients who underwent lateral access fusions. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were used for the systematic review with the search terms "vascular injury" and "lateral lumbar surgery." Of 260 procedures performed at our institution, 211 (81.2%) patients underwent an LLIF and 49 (18.8%) underwent an OLIF. There were no major vascular complications in either group in this comparative study, but there were four (1.5%) minor vascular injuries (2 LLIF, 0.95%; 2 OLIF, 4.1%). Patients who experienced vascular injury experienced a greater amount of blood loss than those who did not (227.5 ± 147.28 vs. 59.32 ± 68.30 ml) (p = 0.11). In our systematic review of 63 articles, major vascular injury occurred in 0-15.4% and minor vascular injury occurred in 0-6% of lateral lumbar fusions. The systematic review and comparative study demonstrate an increased rate of vascular injury in OLIF when compared to LLIF. However, vascular injuries in either procedure are rare, and this study aids previous literature to support the safety of both approaches.

Dural Tear Does not Increase the Rate of Venous Thromboembolic Disease in Patients Undergoing Elective Lumbar Decompression with Instrumented Fusion

OBJECTIVE

Evaluate if dural tears (DTs) are an indirect risk factor for venous thromboembolic disease through increased recumbency in patients undergoing elective lumbar decompression and instrumented fusion.

METHODS

This was a retrospective cohort study of consecutive patients undergoing elective lumbar decompression and instrumented fusion at a single institution between 2016 and 2019. Patients were divided into cohorts: those who sustained a dural tear and those who did not. The cohorts were compared using Student's t-test or Wilcoxon Rank Sum for continuous variables and Fisher exact or chi-squared test for nominal variables.

RESULTS

Six-hundred and eleven patients met inclusion criteria, among which 144 patients (23.6%) sustained a DT. The DT cohort tended to be older (63.6 vs. 60.6 years, P = 0.0052) and have more comorbidities (Charlson Comorbidity Index 2.75 vs. 2.35, P = 0.0056). There was no significant difference in the rate of symptomatic deep vein thrombosis (2.1% vs. 2.6%, P = 1.0) or pulmonary embolus (1.4% vs. 1.50%, P = 1.0). Intraoperatively, DT was associated with increased blood loss (754 mL vs. 512 mL, P < 0.0001), operative time (224 vs. 195 minutes, P < 0.0001), and rate of transfusion (19.4% vs. 9.4%, P = 0.0018). Postoperatively, DT was associated with increased time to ambulation (2.6 vs. 1.4 days, P < 0.0001), length of stay (5.8 vs. 4.0 days, P < 0.0001), and rate of discharge to rehab (38.9 vs. 25.3%, P = 0.0021).

CONCLUSIONS

While DTs during elective lumbar decompression and instrumentation led to later ambulation and longer hospital stays, the increased recumbency did not significantly increase the rate of symptomatic venous thromboembolic disease.