In 2012, a research from the Spine Patient Outcomes Research Trial (SPORT) has provided valuable insights into which patients with intervertebral disc herniation (IDH) benefit most from surgical intervention. By combining a prospective randomized controlled trial with an observational cohort study, researchers aimed to identify factors that modify the treatment effect (TE) of surgery for IDH.

The SPORT study, led by Adam Pearson and his team, sought to determine how individual characteristics influence the effectiveness of surgery compared to nonoperative treatments. Specifically, the study aimed to identify modifiers that affect the difference in outcomes between surgical and nonoperative care for IDH patients.

The study involved 1,192 patients with IDH, divided into two groups: 788 underwent discectomy (surgical group), while 404 received nonoperative care. Researchers used 37 baseline variables to define subgroups and calculate the time-weighted average treatment effect (TE) for the Oswestry Disability Index (ODI) over four years. Variables showing significant interactions with treatment were included in a multivariate model to identify independent predictors of TE.

All subgroups analyzed showed significantly greater improvement with surgery compared to nonoperative care. Key findings from univariate analyses indicated that certain factors were associated with greater surgical benefits. These factors included being married, absence of joint problems, worsening symptoms at baseline, lower education levels, older age, lack of worker’s compensation, longer symptom duration, and a low SF-36 mental component score (MCS).

Three factors emerged as independent modifiers of TE:

1. Marital Status: Married patients experienced a significantly greater TE (-15.8) compared to single patients (-7.7).
2. Joint Problems: Patients without joint problems had a higher TE (-14.6) than those with joint issues (-10.3).
3. Symptom Trend: Those with worsening symptoms at baseline saw a greater TE (-15.9) compared to patients with stable symptoms (-11.8).

The most notable difference was observed in married patients with worsening symptoms, who had the highest TE (-18.3), compared to single patients with stable symptoms (-7.8).

The SPORT study conclusively showed that patients meeting specific criteria for IDH experienced more significant improvements with surgery than with nonoperative treatments, irrespective of individual characteristics. However, the treatment effect was notably higher in patients who were married, without joint problems, and experiencing worsening symptoms. These findings can help guide clinical decisions and personalize treatment plans for individuals suffering from intervertebral disc herniation.

By understanding these key factors, healthcare providers can better identify which patients are likely to benefit most from surgical intervention, ultimately leading to more effective and tailored patient care.

Reference: Pearson, A., Lurie, J., Tosteson, T., Zhao, W., Abdu, W., Mirza, S., & Weinstein, J. (2012). Who should have surgery for an intervertebral disc herniation?: comparative effectiveness evidence from the spine patient outcomes research trial. Spine, 37(2), 140-149.