Introduction: Following trends in healthcare, there has been a shift toward critical longitudinal assessment of subjective and objective outcomes after lumbar spine surgery. Accordingly, the emergence and routine use of real-world institutional registries have been vital to the longitudinal assessment of quality. However, prospectively obtaining longitudinal outcomes for patient 24 months after spine surgery remains challenging. Here, we assessed whether 12-month measures of treatment effectiveness accurately predict long-term outcomes (24 months).
Methods: A nationwide, multi-institutional, prospective spine outcomes registry was utilized. Enrollment criteria included available demographic, surgical and clinical outcomes data. All patients had prospectively collected outcomes measures and 2-year follow-up. Patient reported outcomes instruments (ODI, SF-36, VAS-BP/VAS-LP) were completed before surgery, then at 3, 6, 12, and 24 months after surgery. The Health Transition Index of SF-36 was used to determine the 1-year Minimum Clinical Important Difference (MCID) and logistic regression modeling was performed to determine whether achieving MCID at 1-year adequately predicted improvement and achievement of MCID at 24-months.
Results: The study included 1506 patients: 300 underwent ALIF, 606 underwent TLIF and 600 underwent XLIF. There was correlation between 12- and 24-month ODI (r=0.82; p<0.0001), SF-36 PCS (r=0.89; p<0.0001), VAS-BP(r=0.90; p<0.0001) and VAS-LP(r=0.85; p<0.0001). For ALIF cohort, patients achieving MCID for ODI at 12-months were 13 fold (p<0.0001) more likely to achieve MCID at 24-months. Similarly, for TLIF and XLIF cohorts, patients achieving MCID for ODI at 12-months were 13-fold and 14-fold (p<0.0001) more likely to achieve MCID at 24-months, respectively. 12-months outcomes metrics are predictive of 24-month outcomes for patients undergoing ALIF, TLIF and XLIF procedures.
Conclusions: In a multi-institutional prospective study, patient centered measures of surgical effectiveness obtained at 12-months adequately predict long-term (24-months) outcomes after lumbar spine surgery. Patients achieving MCID at 1-year were more likely to report meaningful and durable improvement by 24 months.
Patient Care: Determining whether a patient has had 'successful' surgical intervention one year earlier can help devise a plan of care earlier.
Learning Objectives: By the conclusion of this session, participants should be able to:
1. Identify patient reported outcomes used for longitudinal assessment of lumbar spine surgery
2. Discuss one-year predictive ability of outcome measures on longer term (e.g., 2-year) outcomes