PLIF and TLIF are sister surgeries. In either surgical technique, the facets should be removed as these facets are useless due to the pars fractures. Leaving the facets do not yield any stability to the post-surgical construct and again, the facets need to be removed to access the bone spur off the inferior aspect of the L5 pedicle.
The technique of PLIF vs. TLIF in a non-isthmic spondylolisthesis surgery is slightly different. In a PLIF, cages are placed in both sides of the disc and generally (although not always), the outer 1/3 to 1/2 of the facets are preserved to allow a region for the posterolateral fusion.
In a TLIF, the entire facet on only one side is removed. This allows the complete uncovering of the exiting nerve and less retraction of the descending (traversing) nerve to place the cage.
In the case of an isthmic spondylolisthesis regardless of PLIF or TLIF, the entire facet on both sides are removed as these facets are already disconnected from the vertebra. The spinous process is generally partially removed (the bottom 1/2 only).
I use to do the PLIF but switched to the TLIF about 8 years ago due to less retraction of the nerve root and a still high fusion rate.
Again, a TLIF for an isthmic spondylolisthesis is a different surgery than a standard TLIF for a degenerative disc. The entire back wall of the vertebra has been sheared off due to the pars fractures (but not the superior facets which remain attached and still function normally). This sheared off back wall is totally non-functional and “hides” the bone spur formation that typically compresses the L5 nerve (at the L5-S1 level). This back wall has no function and leaving it has no purpose but has detriments as noted previously.
Yes, BMP is placed in the disc space to augment fusion.
Recovery time depends upon the patient. There are some patients who walk out of the hospital in 2-3 days only taking tylenol and some that have some pain for 4-5 weeks and use narcotics. I cannot pre-determine the pain levels for the first six weeks.
Review the “recovery by surgery-lumbar fusion” thread on this website. It explains the typical process and stages of recovery.
About one in twenty patients will need oral or IV steroid to reduce inflammation.