The Difference in Superior Adjacent Segment Pathology After Lumbar Posterolateral Fusion by Using 2 Different Pedicle Screw Insertion Techniques in 9-Year Minimum Follow-up
Bibliographic record
Abstract
STUDY DESIGN: A prospective study was performed. OBJECTIVE: To test the hypothesis that different pedicle screw insertion positions would increase the likelihood of superior adjacent segment degeneration (ASD). SUMMARY OF BACKGROUND DATA: Lumbar fusion surgery is a widely accepted treatment of lumbar diseases, such as lumbar stenosis, trauma, tumor, and spondylolisthesis. Fusion and clinical success rates have increased because of improvements in instrumentation and bone graft material. In contrast, numerous complications and problems of fusion surgery have been reported, with ASD being one of the most important. METHODS: This prospective study included 210 patients with low-grade isthmic spondylolisthesis. From January 1999 to December 2003, patients were randomized underwent posterolateral fusion using 2 different pedicle screw insertion positions. The patients were followed up postoperatively and were assessed with regard to radiological and clinical outcomes. Radiological outcomes were assessed mainly on the basis of disc degeneration, facet joint degeneration, and bone fusion. Clinical outcomes were evaluated mainly with the use of visual analogue scale for pain and the Oswestry Disability Index. RESULTS: A total of 178 of 210 (84.7%) patients were available for at least 9-year radiological and clinical follow-up data: 85.3% (87/102) patients in group A and 84.3% (91/108) patients in group B. Bone fusion was achieved in all patients at the last follow-up. ASD was proven in 110 (61.8%) of 178 patients. The incidences of radiographical and symptomatic ASD were 57.9% (103/178) and 3.9% (7/178), respectively. The incidence of ASD in group B was significantly lower than that in group A. Results of clinical outcomes showed lower visual analogue scale and Oswestry Disability Index scores in 2 groups than preoperative scores, but group B had greater improvement on the Oswestry Disability Index scores than group A in patients with ASD. CONCLUSION: The degeneration of superior adjacent segment is closely related to the position of the pedicle screws during lumbar fusion surgery. The position of the pedicle screw farther from the facet joint surface can reduce the degeneration of superior adjacent segment. LEVEL OF EVIDENCE: 3.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".