Preliminary Quantitative MRI Assessment After Combined Posterior Endoscopic Cervical Discectomy and Foraminotomy: An Exploratory Retrospective Cohort Study

Background/Objectives: Posterior endoscopic cervical foraminotomy is an established motion-preserving procedure for selected patients with unilateral cervical radiculopathy. However, isolated foraminal decompression may be insufficient in cases with concomitant foraminal stenosis and lateral soft disk herniation. This preliminary study evaluated clinical outcomes and quantitative MRI changes after combined posterior endoscopic cervical diskectomy and foraminotomy (CEDF) and explored the relationship between postoperative foraminal enlargement and clinical improvement. Methods: This retrospective single-center exploratory cohort study included 15 consecutive patients with single-level unilateral cervical radiculopathy caused by combined foraminal stenosis and lateral soft disc herniation who were treated between 2021 and 2023. All patients underwent CEDF using a posterior full-endoscopic approach. Clinical outcomes were assessed preoperatively, at 6 weeks, and at 12 months using the Visual Analog Scale for arm and neck pain, the Neck Disability Index, and modified MacNab criteria. Quantitative MRI assessment included minimal foraminal diameter, Foraminal Symmetry Index (FSI), and Quantitative Cervical Expansion (QCE). Correlations between radiological and clinical outcomes were analyzed as exploratory, hypothesis-generating analyses. Results: Mean minimal foraminal diameter increased from 1.9 ± 0.7 mm preoperatively to 4.1 ± 0.8 mm postoperatively, with improvement in FSI from 0.40 ± 0.12 to 0.89 ± 0.11. Significant clinical improvement was observed across all outcome measures. Mean arm pain decreased from 7.2 ± 1.3 preoperatively to 1.3 ± 1.4 at final follow-up, while NDI improved from 48.0 ± 14.0% to 18.3 ± 12.0%. The minimum clinically important difference for arm pain reduction was achieved in 14 of 15 patients. A moderate positive exploratory association was observed between foraminal enlargement and reduction in arm pain severity. No major neurological complications, postoperative instability, or revision procedures were observed in this small cohort during the available follow-up. Conclusions: In this preliminary retrospective single-center cohort, CEDF was associated with clinical improvement and measurable postoperative foraminal enlargement in carefully selected patients with unilateral cervical radiculopathy caused by combined foraminal stenosis and lateral soft disc herniation. The observed association between foraminal enlargement and arm pain reduction should be interpreted cautiously because of the small sample size and exploratory design. QCE and FSI should be regarded as preliminary quantitative radiological indices rather than validated markers of decompression adequacy or clinical response. Larger prospective comparative studies are required to validate these findings and define the role of CEDF among established cervical decompression procedures.