415 - Global Cervical Sagittal Alignment, Balance and Segmental Contribution...

#415 Global Cervical Sagittal Alignment, Balance and Segmental Contribution: Radiographic Outcomes of Three and Four Level Disc Replacement with NuNec and Prestige LP Implants

Cervical Therapies and Outcomes

Poster Presented by: A. Berg

Author(s):

A.J. Berg (1)
R.P. Jeavons (1)
G. Reddy (1)
T. Friesem (1)

(1) University Hospital of North Tees, Spinal Unit, Stockton on Tees, United Kingdom

Abstract

Introduction: Cervical disc replacement provides an alternative to fusion; maintaining motion, restoring alignment and relieving stenosis related symptoms. Little outcome data is available for 3 or 4 level surgery. We present radiographic outcome data.

Aims: Assess the ability of different cervical disc replacements to improve global cervical sagittal alignment and balance and to assess the segmental contribution of each disc replacement to the global sagittal balance.

Methods: Review of radiographic data regarding NuNec (Pioneer Surgical Technology. USA) and Prestige LP (Medtronic Ltd. UK ) cervical disc replacements over 5 years.

57 patients included.

3 level: Nunec n=31; Prestige n=15

4 level: Nunec n=10; Prestige n=1

Lateral neutral, flexion and extension radiographs analysed (pre-operative, initial post-operative and recent follow-up (FU)) for:

Global Cervical Sagittal Alignment

- Cobb angle from inferior end plates of C2 - C7 on lateral neutral radiographs

Global Cervical Sagittal Balance.

- Difference between Cobb angle from inferior end plates of C2 - C7 in flexion and extension.

Segmental Contribution

- Posterior vertebral body angle of replaced segments.

Results: At current follow-up.

Mean time since surgery:

3 level: NuNec = 24.52 months; Prestige = 39.8 months

4 level: NuNec = 23.9 months; Prestige = 10 months

Conclusions: 3 level NuNec improves global sagittal alignment and sagittal balance but there does not appear to be a correlation with the observed segmental contributions. Prestige showed reduced global sagittal alignment and sagittal balance which was supported by a segmental loss at each level.

4 level NuNec and Prestige improve global sagittal alignment but show reduced global sagittal balance post operatively. There does not appear to be a correlation with the observed segmental contributions.

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