A retrospective review of outcomes for single and multilevel ACDF with a zero-profile stand-alone device vs traditional plate-and-cage implants

Thursday, June 1, 2023

8:30 AM – 6:15 PM

Location: Salons 7-8

Presenting Author (Person doing the Podium Present(s)

Robert Kamil, BS

Medical Student Research Fellow
Hospital for Special Surgery, United States

View E-Poster

Co-Author(s)

AP

Anthony Pajak, BS

Hospital for Special Surgery, United States
AK

Andrew Kim, BA

Hospital for Special Surgery, United States
TA

Tomoyuki Asada, MD

Hospital for Special Surgery, United States
GK

Gregory Kazarian, MD

Hospital for Special Surgery, United States
TA

Troy Amen, MD, MBA

Hospital for Special Surgery, United States
AK

Austin Kaidi, MD

Hospital for Special Surgery, United States
YO

Yousi Oquendo, MD

United States
OB

Olatunde Badejo, MD

United States
NV

Nathan Varady, MD

United States
RM

Robert Merrill, MD

Hospital for Special Surgery, United States
MJ

Michell Johnson, MD

Hospital for Special Surgery, United States
KA

Kasra Araghi, BS

Research Fellow
Hospital for Special Surgery
Scottsdale, Arizona, United States
MK

Maximillian Korsun, BS

Hospital for Special Surgery, United States
OT

Olivia Tuma, BS

Hospital for Special Surgery
New York, New York, United States
SS

Sumedha Singh, MD, MBBS

Hospital for Special Surgery, United States
NS

Nishtha Singh, MBBS

hospital for special surgery, United States
SI

Sravisht Iyer, MD

Assistant Attending, Spine Surgery
Hospital for Special Surgery
New York, New York, United States
JD

James E. Dowdell, MD

Spine Fellow
Hospital for Special Surgery
New York, New York, United States
JF

James Farmer, MD

Surgeon
Hospital for Special Surgery
New York, New York, United States
TA

Todd J. Albert, MD

Professor
Hospital for Special Surgery
New York, New York, United States
RH

Russel C. Huang, MD

Surgeon
Hospital for Special Surgery
New York, New York, United States
HS

Harvinder S. Sandhu, MD

Surgeon
Hospital for Special Surgery
New York, New York, United States
SQ

Sheeraz A. Qureshi, MD, MBA

Attending Surgeon
Hospital for Special Surgery
York, New York, United States
HK

Han Jo Kim, MD

Surgeon
Hospital for Special Surgery
New York, New York, United States

Submitter(s)

HS

HSS SpineTeam

New York, New York, United States

Disclosure(s):

Robert Kamil, BS: No financial relationships to disclose

Anthony Pajak, BS: No financial relationships to disclose

Tomoyuki Asada, MD: No financial relationships to disclose

Robert Merrill, MD: No financial relationships to disclose

Nishtha Singh, MBBS: No financial relationships to disclose

Sravisht Iyer, MD: No financial relationships to disclose

Introduction: In recent years, increasing numbers of cervical disease cases have been treated with zero-profile devices (Zero-p) in anterior cervical discectomy and fusion (ACDF). However, the evidence for long-term efficacy for different surgical levels in the literature remains insufficient.
Aims/

Objectives: The aim of this study was to compare the clinical efficacy of the Zero-p with that of the traditional cervical plate-and-cage implants in patients undergoing 1, 2, 3, and 4 level ACDF.

Methods: 1500 adult patients (18-80 years old) who underwent primary ACDF by 7 surgeons at a single institution between 01/2016 and 09/2022 were included. Fusion rates were assessed at least 1 year postoperatively via CT scans and Flexion/Extension Radiographs. Patients with any concurrent procedures (i.e. Posterior cervical fusion, hybrid cervical disc arthroplasty, etc.), revision spinal procedures, metabolic bone diseases (ie. Osteoporosis), active inflammatory arthritis, chronic steroid use, CKD stages 4 and 5 (eGFR 30 ml/min), non-English speaking, or required the use of BMP during fusions were excluded. Propensity score matching was utilized to determine the plate/cage group and standalone group using variables including age, sex, BMI, preoperative CCI scores, and surgical level (single or multiple level). The matched tolerance was the standard deviation of the propensity scores multiplied by 0.20. The final cohorts yielded 54 patients from each group. Continuous values and categorical values were compared with independent t-test and chi square test, respectively. All statistical analysis was performed with SPSS ver.22 and statistical significance was taken at p-value < 0.05.

Results: 54 patients were included in the standalone group. The mean age was 57.1 +/- 10.3 years, the mean BMI was 27.0 +/- 4.5 kg/m2, 40.7% of the patients were female, and CCI scores were distributed 0 (81.5%), 1 (13%), 2 (3.7%), and 3 (1.9%). The surgical levels in the stand-alone group were also distributed 1 (40.7%), 2 (44.4%), 3 (14.8%), and 4 (0%). 54 patients were included in the matched plate/cage group. The mean age was 58.7 +/- 12.8, the mean BMI was 26.8 +/- 4.1, 37% of the patients were female, and CCI scores were distributed 0 (68.5%), 1 (18.5%), 2 (11.1%), and 3 (1.9%). The surgical levels in the plate/cage group were distributed 1 (40.7%), 2 (31.5%), 3 (25.9%), and 4 (1.9%). There were no significant differences in fusion rates at 1 year for all matched surgical levels (p-value = 0.627, table 1). Among patients who underwent a single level ACDF, there were no significant differences in fusion rates between standalone (81.8%) and cage/plate group (90.9%) (p-value= 0.380, table 2). Similarly, among those who underwent multilevel ACDF, there were no significant differences in fusion rates between standalone (75.0%) and cage-plate groups (78.1%) (p-value= 0.768, table 2).

Conclusions: Although the overall fusion rate for the standalone groups was 77.8% and the overall fusion rate for the plate/cage groups was 83.3%, both fusion cohorts yielded no statistically significant difference for single level and multilevel ACDFs.