Radiographic Outcomes Following ACDF With Hyperlordotic Implants to Achieve Cervical Anterior Column Realignment

Background: Degenerative disc disease and progressive sagittal malalignment can both contribute to degenerative cervical myelopathy and radiculopathy. For patients with symptoms refractory to conservative management, anterior cervical discectomy and fusion (ACDF) is a thoroughly vetted intervention shown to improve pain and disability measures. Hyperlordotic implants can also help restore cervical sagittal balance through anterior column realignment (ACR).

Methods: A consecutive bi-institutional series of patients who underwent ACDF with hyperlordotic polyetheretherketone (PEEK) implants between 2014 and 2016 was reviewed. All included patients underwent ACDF between C3 and C7 inclusive of a hyperlordotic PEEK cervical implant (>10° lordosis), and had ≥12 months of radiographic follow-up. Lateral radiographs were analyzed to compare pre- and postoperative cervical parameters.

Results: Forty-six patients were included (mean age, 58.0 years; male, 35%). Mean body mass index was 28.3 kg/m², and mean radiographic follow-up 14.4 months. Overall, cervical lordosis increased from -7.8° preoperatively to -14.8° postoperatively and to -15.7° at last follow-up (P < 0.001). Additionally, the mean segmental lordosis of ACR levels treated increased from -0.2° preoperatively to -4.8° postoperatively (P < 0.001), but no significant change was observed at last follow-up. Lastly, improvement in segmental lordosis was seen at both postoperative time points at the C3-C4 (P = 0.002 and P = 0.005, respectively), C4-C5 (P < 0.001 and P < 0.001, respectively), and C5-C6 levels (P < 0.001 and P < 0.001, respectively).

Conclusions: Our study demonstrates that hyperlordotic PEEK implants used for ACR effectively contribute to restoration of cervical lordosis in patients undergoing ACDF, potentially reducing the need for additional posterior surgery.