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Author Spotlight: Scope of LE-ULBD as a Safe, Effective, and Minimally Invasive Approach to Treat Lumbar Spinal Stenosis
Published on: February 9, 2024
Pre- and postoperative MRI analysis of central decompression in MIS fusion with lumbar stenosis
Laura Marie-Hardy1, Marc Khalifé2, Peter Upex2
1Service d'orthopédie et traumatologie, université Paris Sorbonne, hôpital de la Pitié-Salpêtrière, 47, boulevard de l'Hôpital, 75013 Paris, France.
Objectives:
Mini-invasive approaches have grown substantially these last decades in spinal surgery, notably for lumbar decompressions and fusion, with advantages over open approaches in terms of morbidity reduction. However, to our knowledge, no study has measured on MRI the amount of central decompression obtained by MIS approach. The goal of this study was to precisely measure the decompression of central stenosis by unilateral MIS approaches.
Methods:
The files of 42 patients that had a MIS lumbar fusion with central decompression for central stenosis were reviewed. All patients had a pre- and postoperative MRI that allowed on T2 axial images to classify the central stenosis, according to Schizas' classification, and measure the dural sac cross-sectional area (DSCA) and the anteroposterior diameter (DAP). The statistical analysis was made with paired t-test.
Results:
Fifty-six levels were analyzed, mostly L4L5 (58%). The mean preoperative DSCA was 70.53mm2 and the mean postoperative DSCA was 172.2mm2. The mean preoperative DAP was 6.15mm and postoperative was 10.68mm. Preoperatively, the levels analyzed were rated B, C or D according to Schizas for 53 out of 56 levels and A1-4 for 51 out of 56 levels in postoperative. All the results were statistically significant (p<0.001).
Conclusion:
Decompression, assessed by MRI, seems to be equivalent by MIS approach to open laminarthrectomy. MIS approaches have been studied clinically in these indications with very satisfying results. As a conclusion, MIS approaches seems to be a relevant and efficient option in the treatment of lumbar degenerative stenosis.
Level Of Evidence:
IV, retrospective study.
Insights
Mini-invasive surgery (MIS) for lumbar stenosis effectively decompresses the central spinal canal, as shown by MRI measurements. This approach offers comparable results to open surgery, making it a viable option for treating degenerative spinal stenosis.
Area of Science:
- Neurosurgery
- Orthopedic Surgery
- Spinal Imaging
Background:
- Minimally invasive surgery (MIS) offers reduced morbidity compared to open spinal procedures.
- Central spinal stenosis treatment often requires decompression.
- Quantifying central decompression via MIS using MRI is not well-established.
Purpose of the Study:
- To quantitatively assess the degree of central spinal canal decompression achieved by unilateral minimally invasive surgery (MIS) for lumbar stenosis using MRI.
- To compare pre- and postoperative dural sac dimensions.
Main Methods:
- Retrospective review of 42 patients undergoing MIS lumbar fusion with central decompression.
- Pre- and postoperative MRI analysis of dural sac cross-sectional area (DSCA) and anteroposterior diameter (DAP).
- Classification of stenosis severity using Schizas' classification.
Main Results:
- Significant increase in mean DSCA from 70.53 mm² to 172.2 mm² (p<0.001).
- Significant increase in mean DAP from 6.15 mm to 10.68 mm (p<0.001).
- Postoperative MRI showed significant improvement in stenosis grading for most levels analyzed.
Conclusions:
- MRI-based assessment indicates that MIS achieves significant central decompression, comparable to open laminarthrectomy.
- MIS is a relevant and effective surgical option for lumbar degenerative stenosis.
- Clinical outcomes for MIS in these indications are highly satisfactory.
