J Minim Invasive Spine Surg Tech.  2019 Jun;4(1):5-13. 10.21182/jmisst.2019.00017.

Effect of Indirect Neural Decompression by Minimally Invasive Oblique Lumbar Interbody Fusion in Adult Degenerative Lumbar Spine Disease and Its Limitations

• Parikh NP
• Mistry M
• Jhala AC

• KMID: 2562047
• DOI: http://doi.org/10.21182/jmisst.2019.00017

Abstract

Objective
To study efficacy of minimally invasive oblique lumbar interbody fusion (MIS OLIF) to achieve indirect decompression in degenerative lumbar spine disorders. To find out amount of indirect decompression achieved by assessing clinical and radiological outcomes. To find out limitations of indirect decompression.
Methods
OLIF was carried out in 60 segments/45 patients having degenerative lumbar spine disorders from May 2016 to April 2018. Patients with infection, trauma, lumbar disc prolapse and listhesis >grade 3 were excluded. 53 segments had posterior and 7 segments had anterior fixation. Auto graft was used in 21 and artificial bone graft in 24 patients. Indirect decompression by MIS OLIF was achieved in all patients. Neuromonitioring was not used. Clinical assessment was done using Modified Macnab’s criteria. Radiological assessment was done on X-rays and MRI. Percentage improvement in foraminal height, disc height, segmental lordosis, spinal canal area and reduction in listhesis were measured. Statistical assessment was done using Paired‘t’ test.
Results
60 segments of 45 consecutive patients were operated with 15 of them male and 30 female. Average age was 63 years. Minimum follow-up was for 1 month and maximum follow-up was for 18 months with average of 11 months. Single segment fusion was done in 31, 2 segment fusion in 13 and 3 segment fusion in 1 patient. Clinically 33 (73.33%) had excellent, 11 (24.44%) had good & 1 (2.22%) had fair outcomes. None required direct decompression. Radiologically; foraminal height improved by 26.27%, disc height 92.1%, segmental lordosis 3.4° and listhesis reduction was 6.8°, 41 segments studied on MRI had improvement in spinal canal area of 42.7%.
Conclusion
Indirect decompression by MIS OLIF is effective in decompressing the spinal canal with good radiological and clinical out comes. Direct decompression is avoidable with help of interbody distraction using OLIF particularly in patients with Schizas grade A, B, and C of lumbar spinal stenosis.

Keyword

Indirect decompression; OLIF; Degenerative lumbar spine