Improved foraminal expansion and pain scores following placement of novel expandable interlaminar stabilization device for lumbar spinal stenosis.

STUDY

DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate radiographic durability and clinical outcomes following placement of a novel expandable interlaminar stabilization device for single-level lumbar spinal stenosis. Specifically, we aimed to: 1) quantify immediate postoperative posterior column distraction; 2) determine whether foraminal expansion is improved postoperatively without radiographic subsidence; and (3) assess potential improvements in patient-reported pain/clinical outcomes.

METHODS

A retrospective review was performed of adult patients undergoing single-level decompression supplemented by an interlaminar device for symptomatic lumbar spinal stenosis by a single surgeon from 2024 to 2025. Radiographic parameters included anterior, middle, and posterior disc height, foraminal height, and segmental lordosis that were measured preoperatively and longitudinally through 12 months. Postoperative changes were assessed relative to preoperative using paired t-tests, with longitudinal trends analyzed by linear mixed-effects modeling. Clinical outcomes were assessed using Visual Analog Scale (VAS) pain scores. Complications and reoperations were recorded, with statistical significance defined as P < 0.05.

RESULTS

A total of 33 patients (mean age 72.6 ± 10.0 years) were included. Posterior disc height increased from 0.46 cm to 0.58 cm (mean +0.12 cm, P < 0.001), and foraminal height increased from 1.88 cm to 2.13 cm (mean +0.26 cm, P < 0.001). There were no significant changes in anterior disc height, middle disc height, or segmental lordosis. Mixed-effects modeling demonstrated no progressive loss of posterior disc height/foraminal expansion through 12 months postoperatively. Mean VAS improved from 6.8 preoperatively to 4.5 at latest follow-up (mean -2.36, P < 0.001). 31/33 patients (93.9%) had no perioperative complications; two (6.1%) required hardware removal following unrelated postoperative trauma or spinous process fracture.

CONCLUSIONS

Expandable interlaminar stabilization produced immediate posterior column distraction and foraminal expansion improved at 12 months postoperatively. Clinically meaningful pain reduction was observed in this lumbar stenosis cohort. Our findings support the biomechanical durability and clinical efficacy of interlaminar posterior column stabilization as an adjunct to decompression.