The Impact of Lumbar Partial Microdiscectomy for Vertebral Ring Apophyseal Fractures in Adolescents on PROMIS Pain, Physical Function, and Mental Health Domains.

Background: Lumbar partial microdiscectomy (LPM) in adolescents is an infrequently performed procedure, reserved for pain and neurological symptoms unresponsive to nonsurgical management. Most studies have focused on the interventional impact on pain outcomes creating a paucity of data on physical function and mental health outcomes. The study hypothesis is LPMs in adolescents will provide improvements in measured PROMIS domains (mental health, physical function, and pain) at 2 years postoperatively.

Methods: This study is a retrospective analysis of patients under 21 years of age who underwent LPM surgery by 2 surgeons at a tertiary-care pediatric hospital. PROMIS scores [mobility (MOB), pain interference (PI), upper extremity (UE), physical functioning (PF), peer relationships (PR), anxiety, and depression] were obtained preoperatively and 6 weeks, 3 months, 6 months, 1 year, and 2+ years postoperative. The changes in PROMIS scores were then analyzed and compared at each time point using a mixed model analysis.

Results: Thirty-six patients with a mean age of 16.6 years (range: 13 to 20 y) at surgery were included in the analysis (2015 to 2022). All patients underwent nonsurgical treatments, which varied according to symptom type and severity and included over-the-counter medications, pain management or physiatry consultations, physiotherapy, selective nerve root and epidural injections, and bracing for a minimum of 3 months. Preoperatively, 4 patients had motor weakness, 11 lower extremity numbness, and 35 lower extremity radicular pain. Postoperatively, there were improvements for MOB ( P ≤0.05) at each time point, with an estimated mean difference of +11.3 at 2 years ( P= 0.0027). In PI there was a significant decrease ( P ≤0.0001) immediately after surgery with sustained improvement (-8.6) at 2 years ( P= 0.0009). For UE and PR, there was a statistically significant improvement from the preoperative baseline scores to the 1-year postoperative visit for UE (+10.6; P =0.008) and PR (+8.0; P =0.01), but no difference at 2 years. PF, anxiety, and depression domains did not demonstrate any statistically significant changes.

Conclusion: Using the PROMIS instrument, there were significant improvements postoperatively after LPM in adolescents in MOB, PI, UE, and PR up to 1 year postoperatively, and continued improvement in MOB and PI. These data demonstrate LPM can provide sustained improvement in PROMIS domains up to 2 years of follow-up after surgery.

Level of evidence: Level III-retrospective, single cohort study.