Subsidence of the Wing titanium cage after anterior cervical interbody fusion: 2-year follow-up study

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Cage subsidence occurs after anterior cervical discectomy and fusion (ACDF). The aim of this prospective study was to evaluate subsidence and total segmental height after implantation of a newly designed Wing titanium cage. Furthermore, alignment of the entire cervical spine was analyzed 2 years after surgery.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Fifty-four patients (26 women and 28 men) whose mean age was 48.3 years underwent ACDF. Follow-up examinations were performed at discharge and 6, 12, and 24 months postoperatively by an independent investigator. The clinical course was evaluated using the visual analog pain scale and the Prolo scales. Measurements of subsidence and total segmental height were conducted, and the alignment of the entire cervical spine was classified using two methods.</jats:p> <jats:p>In 54 patients 64 levels were fused. The patients noted a significant reduction of pain, and scores on both Prolo scales were significantly improved. At the 2-year follow-up examination, subsidence was present in 30 of the 67 fused segments. There was a statistically significant correlation between subsidence and the presence of posterior spondylosis at the initial surgery. Furthermore, there was a significant correlation between reduction of total segmental height and the presence of subsidence; however, subsidence did not prevent the development of a solid bone arthrodesis (fusion rate 98%) or have an adverse effect on the alignment of the cervical spine.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Titanium Wing cage–augmented ACDF was associated with comparatively good long-term results. Subsidence was present but did not cause clinical complications. Furthermore, radiological studies demonstrated that the physiological alignment of the cervical spine was preserved and a solid bone arthrodesis was present at 2 years after surgery.</jats:p></jats:sec>

Cage subsidence does not, but cervical lordosis improvement does affect the long-term results of anterior cervical fusion with stand-alone cage for degenerative cervical disc disease: a retrospective study

“…Gercek et al [10] reported that 5 of 8 patients (9 levels, 62.5%) had radiological signs of cage subsidence and recommended additional stabilization is necessary to avoid this problem though cage subsidence did not correlate with clinical symptoms. In a prospective study [22], subsidence was present in 30 of the 67 (44.8%) fused segments of ACDF using a titanium cage, but the height of the foramen was well maintained among the subsidence cases. The occurrence of local kyphosis was rare and did not cause any clinical complications after 2 years follow-up.…”

Comparison of titanium and polyetheretherketone (PEEK) cages in the surgical treatment of multilevel cervical spondylotic myelopathy: a prospective, randomized, control study with over 7-year follow-up

“…Cage subsidence is the most considered problem for stand-alone cage technology. Subsidence of titanium cages is observed in 13 to 45 % of cases in larger series [3,25]. The reported rate of PEEK cage subsidence varies from 8 to 15 % [13,35].…”

Three- and four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct

“…This phenomenon may occur due to insufficient fixation power of the cage alone. Indeed, some surgeons [5,7,8,14,15] have reported a significantly higher incidence of cage subsidence and subsequent local kyphosis in patients who received a cage alone compared to patients who received plate augmentation. Furthermore, fusion time was significantly delayed in these studies, and the fusion rate was significantly lower amongst patients who had the cage alone compared to those who had plate augmentation.…”

“…The cage can provide stability, high fusion rates and low subsidence [12][13][14][15]. There are many studies [5,6,12] on the favourable results of one-or twolevel anterior cervical fusion using a PEEK (polyetheretherketone) cage in degenerative cervical spine disease, including our previous report [5,12].…”