One-year patient reported outcomes after single-level lumbar fusion at orthopedic specialty hospital compared to tertiary referral center

Background context: Lumbar spinal fusion is an increasingly common operation to treat symptoms related to degenerative disorders of the spine including radiculopathy and pain. As the volume of spine surgeries grows, it is becoming increasingly common for procedures to take place in nontertiary care centers, including orthopaedic specialty hospitals (OSH). While previous research demonstrates that surgical outcomes at an OSH are noninferior to those at a tertiary referral center (TRC), the implications of this difference on patient-reported outcome measures (PROMs) have not been sufficiently assessed.

Purpose: The objectives of this study were (1) to determine if changes in patient reported outcome measures (PROMs) after elective lumbar spinal fusion surgery differ between patients who undergo surgery at an orthopedic specialty hospital (OSH) and those who undergo surgery at a tertiary referral center (TRC) and (2) to characterize differences in short-term outcomes between hospitals.

Study design: Retrospective cohort study.

Patient sample: Adult patients (≥18 years old) who underwent primary, elective single-level posterior lumbar decompression and fusion between January 2014 and December 2021 at a tertiary referral center or an orthopaedic specialty hospital.

Outcome measures: PROMs: Oswestry Disability Index (ODI), Short-form 12 (SF12) Mental Component Summary (MCS); SF12 Physical Component Summary (PCS); Visual Analogue Back and Leg (VAS Back/Leg).

Methods: PROMs were collected preoperatively, 6 months after surgery, and 1 year after surgery. Six-month and 1-year delta PROM values were calculated by subtracting the preoperative PROM score from the 6-month or 1-year score, respectively. Multivariable linear regression analyses were conducted to assess the independent effect of hospital location on postoperative PROM scores.

Results: A total of 288 patients were identified as part of the study cohort including 205 patients who underwent surgery at the tertiary hospital and 83 patients who underwent surgery at the OSH. OSH patients had shorter length of stay (1.57±0.72 vs 3.28±1.32, p<.001), however there was no difference in discharge disposition or 90-day readmission rates between hospitals (p>.05). At 6 months, having surgery at the specialty hospital was associated with higher PCS (estimate=2.96, confidence interval: 0.21-5.71, p=.035). At 1-year postoperatively, the location of surgery no longer demonstrated significant associations with PROM scores. Preoperative PROM scores demonstrated significant associations with 6-month and 1-year scores for each PROM (p<.05) except VAS leg at 6 months postoperatively.

Conclusion: To our knowledge, this is one of the largest studies investigating PROMs at OSH versus TRCs for single-level lumbar fusions. We demonstrated that at 1-year follow-up, there is not a significant difference in PROM improvement between patients who undergo surgery at a TRC and patients who do so at an OSH.