Should We Re-Instrument the Originally Fused Level in ACDF Revision for Adjacent Segment Disease?: A Quality Outcomes Database Study.

STUDY

DESIGN

Retrospective cohort.

OBJECTIVE

To investigate differences in perioperative variables, patient-reported outcomes measures (PROMs), and reoperation rates between revision involving reinstrumentation of the originally fused level versus fusion of the adjacent segment alone in revision ACDF patients.

SUMMARY OF BACKGROUND DATA: Adjacent segment disease (ASD) continues to be a significant issue for patients undergoing anterior cervical discectomy and fusion (ACDF) surgery. Reinstrumenting the originally fused segment provides greater biomechanical stability. However, there remains a paucity of research investigating the differences in outcomes between patients undergoing reinstrumentation of the originally fused level versus only the adjacent segment level.

METHODS

Patients who underwent single-level, adjacent segment revision ACDF were identified from the Quality Outcome Database. The primary exposure was reinstrumentation of the original segment. Patient characteristics were compared. Outcomes were perioperative variables, 3-month and 12-month reoperation, and 3-month, 12-month, and 24-month PROMs, including numeric rating scale for neck and arm pain, neck disability index, EuroQol 5 Dimensions, and modified Japanese Orthopaedic Association scores. Multivariable regression models were fitted for each outcome.

RESULTS

Of the 767 patients undergoing revision ACDF, 25.0% had reinstrumentation. On analysis, patients with reinstrumentation had greater blood loss (60.7±11.6 vs. 40.9±10.8 mL, P  < 0.001), operative time (123.8±8.0 vs. 93.8±7.4 mins, P  < 0.001), and hospital length of stay (1.63±0.35 vs. 1.30±0.26 d, P  = 0.004) than patients with single-level fusion alone. There was no difference in neck and arm pain, NDI, and mJOA PROMs at 3-months, 12-months, and 24-months between groups ( P  > 0.05). Further, there was no difference in reoperation rates at 3-months (4.3% vs. 3.2%, P  = 0.154) and 12-months (5.7% vs. 4.5%, P  = 0.194).

CONCLUSIONS

Given comparable PROMs and reoperation rates, when clinically feasible, surgeons may consider avoiding reinstrumentation of the original ACDF fusion, opting for a more conservative single-level revision to minimize the negative risks/complications associated with increased perioperative blood loss, operative time, and length of stay.