Introduction: With the increasing frequency of spine surgery,1-6 there is an important need to demonstrate the effectiveness of these procedures to provide clinical benefit.7, 8 Patient reported outcomes (PROs) have become the standard measurement of recording outcomes, with achieving a minimally clinically important difference (MCID) of the PRO being considered a successful surgery. We sought to identify which patient characteristics that increase the likelihood of achieving EQ-5D MCID after lumbar spine surgery.

Methods: The Michigan Spine Surgery Improvement Collaborative (MSSIC) is a statewide multicenter quality improvement collaborative.9 Using MSSIC, we identified 2493 patients at 90d,1583 patients at 1yr, and 439 patients at 2yr with complete EQ-5D data. Multivariate logistic regression models were constructed to identify risk factors for achieving MCID. EQ-5D MCID was defined as a change of 0.15.

Results: At 90d follow-up, 56.48% achieved EQ-5D MCID. At 1yr follow-up, 56.6% achieved MCID. At 2yr follow-up, 53.53% achieved MCID. Factors that decreased likelihood of achieving EQ-5D MCID at 90d, 1yr and 2yrs include higher baseline EQ-5D (p<0.001), liability (p<0.04), depression (p=0.002), and symptoms =3mo (p<0.001). Factors that decreased likelihood of achieving EQ-5D MCID at 90d and 1yr include lower baseline ODI (p<0.001), higher baseline back pain score (p<0.004), workman’s comp (p<0.04), tobacco usage (p<0.033). Opioid usage =6mo decreased likelihood of achieving EQ-5D MCID at 1yr and 2yr (p<0.001). Factors that decreased likelihood of achieving EQ-5D MCID at 1yr only include lower income (p<0.05), unemployment (p<0.032), anxiety (p<0.001), and having spinal stenosis (p<0.025). Factors that decreased likelihood of achieving EQ-5D MCID at 90d only include public insurance (p<0.04), BMI=30 (p<0.04), previous spine surgery (p<0.001), and predominant back pain (p<0.04).

Conclusions: We identified patient characteristics that influence the likelihood of achieving MCID. Knowledge of these characteristics can be potentially be useful in prognosticating clinical benefit after surgery.

Patient Care: My research will improve patient care by identifying which patients are more likely to undergo a successful lumbar spine surgery.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of minimally clinically important difference (MCID) 2) Describe which patient demographic factors increase or decrease likelihood of achieving EQ-5D MCID

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