Does Interbody Height and Material Influence Radiographic Pseudarthrosis in ACDF? Insights From a Single-Institution Study.

STUDY

DESIGN

Single-institution retrospective cohort study.

OBJECTIVE

Determine the impact of graft height and material on radiographic pseudarthrosis, pseudarthrosis requiring reoperation, and patient-reported outcome measures (PROMs).

SUMMARY OF BACKGROUND DATA: The success of an anterior cervical discectomy and fusion (ACDF) depends on obtaining solid bony fusion to achieve stability and restore disc height. While various interbody graft options exist, the impact of graft height and material on fusion rate remains an area of ongoing investigation.

METHODS

Patients who underwent 1-3 level primary ACDF between 2010 and 2021 were studied. Graft height and material (structural allograft vs. prosthetics) were the primary independent variables. The primary outcome was pseudarthrosis, defined as interspinous motion >2 mm on flexion-extension lateral x-rays at 1-year postoperatively. PROMs included Numeric Rating Scale-Arm/Neck and Neck Disability Index. Multivariable logistic regression was performed. A subanalysis was conducted for prosthetic submaterial (PEEK vs. titanium).

RESULTS

One hundred fifty-three patients were included (mean age: 51.8±11.0 y; 42.5% male). Most patients had 1-2 levels operated on and 33.3% had structural allograft as the interbody implant. Prosthetic implants were used in 66.7% of patients, with PEEK being the most common (80.4%). At 1-year postoperatively, 11.1% of patients developed pseudarthrosis, and 2.0% underwent reoperation. There were no significant differences in graft height, material, or prosthetic submaterial between patients with and without pseudarthrosis. Multivariable logistic regression also did not show any significant associations between graft height, material, or prosthetic submaterial with pseudarthrosis, reoperation, or PROMs (all P >0.05).

CONCLUSION

This study found that graft height and material did not significantly affect pseudarthrosis, reoperation, or PROMs in patients undergoing primary ACDF. While graft height and composition alone may not be critical determinants for fusion success in ACDF, Other factors, such as patient-specific characteristics and surgical technique may contribute to the risk of pseudarthrosis and should be explored in future studies.

LEVEL OF EVIDENCE: Level III.