After L4-L5 lumbar fusion fixation, are adjacent segments more likely to degenerate?

   A large number of patients have degenerative diseases such as lumbar disc herniation, and the segments are all L4-L5. When the regular conservative treatment is not effective, some patients need to undergo surgical treatment. Lumbar spine fixation and fusion surgery is one of the common surgical procedures, that is, the common operation of “nailing”. This operation is suitable for lumbar spine surgery for various degenerative diseases. It has obvious effects on symptom relief and lumbar segment stability reconstruction, but there is a problem that both patients and doctors are concerned about:   L4-L5 After lumbar fixation and fusion surgery Will there be problems with the adjacent segments? Will there be adjacent vertebral disease (ASD)? After L4-L5 nails are fixed, the two adjacent segments L3-L4 and L5-S1 below will be Wouldn’t it be easier to degenerate? The answer is that this may happen. The reason is that the local lumbar spine fusion fixation will change the stress on the adjacent segment of the lumbar spine, increase the active load of the adjacent segment, and then accelerate the degeneration of the adjacent disc. As more and more lumbar spine fusion fixation operations are carried out, a considerable proportion of the adjacent segmental degeneration (ASD) of the fused vertebral body, and some of them have symptoms and have to be operated again. How to solve this problem? Some surgeons believe that if L4-S5 intervertebral disc degeneration is found at the same time during L4-L5 vertebral body fusion fixation, it is necessary to prevent A5-S1 level postoperative ASD. Extend the fusion to the sacrum to prevent further surgery. Is it necessary to do this? Can the problem be solved? In this way, the operation will increase the cost and cause financial burden to the patient, etc… For the time being, we will still call a big “question mark”!   Related research published in “Neurosurgery” in May, PrognosticFactorsforAdjacentSegmentDiseaseAfterL4-L5LumbarFusion (Analysis of prognostic factors of adjacent segment lesions after L4-L5 lumbar spine fusion) Further analysis was made to this problem.  Adjacent segmental disease (ASD) is an important consideration in the decision-making process of lumbar fusion surgery. The purpose of this study was to determine the risk factors for ASD after L4-L5 fusion and the difference between the incidence of proximal and distal ASD. (Proximal L3-4. Distal L5-S1)    1. The incidence of distal (L5-S1) ASD is very low. A retrospective analysis of 131 cases of lumbar 4-5 fusion fixation due to lumbar 4-5 degenerative disease According to the clinical data of the patients, it was found that among these 131 patients, the incidence of ASD requiring reoperation was 25.2%. 24 cases (accounting for 18.3% of the total 131 cases) developed near-segment ASD (L3-L4), 3 cases (2.3%) developed distal (L5-S1), and 6 cases (4.6%) developed bilateral ASD (including Near and far). Cumulatively, the incidence of far-end ASD is much lower than that of near-end ASD, which means that the ASD occurring in L5-S1 is much less than that in L3-L4.  The figure shows: 18.3% occurs at the proximal end (L3-L4), 2.3% occurs at the distal end (L5-S1), and 4.6% occurs at both sides.   2. It is more important to consider the proximal (L3-L4) ASD!    This picture is from a 57-year-old female patient who presented with a proximal (L3-L4) ASD after L4-5 fusion fixation. Before surgery, the patient developed L4-L5 intervertebral disc herniation (to the right), with severe right lumbar 4 nerve root compression, L4-L5 lumbar spondylolisthesis (grade I), and severe bilateral crypt stenosis. The patients were subjected to L4-L5 laminectomy and L4-L5 right distal decompression, and posterior fixation and fusion were performed with autogenous bone and granular allograft pedicle screws at L4-L5 (Figures A and B are: X-rays of lumbar spine before and after and after surgery). One year after surgery, the patient developed severe low back pain, accompanied by left nerve root symptoms and left foot droop. MRI showed (Figure C) ASD in L3-L4, with moderate stenosis and compression of the left L4 nerve root. Figures D and E show the postoperative image after re-operation, re-apparatus revision at L4-L5, and extension and fixation to L3-L4, while performing autogenous and allogeneic bone