PEEK Cages versus PMMA Spacers in Anterior Cervical Discectomy: Comparison of Fusion, Subsidence, Sagittal Alignment, and Clinical Outcome with a Minimum 1-Year Follow-Up

Table 4

Comparison of sagittal alignment, subsidence, pain level, and functional outcome according to fusion status.

	PEEK; cage	PMMA; Sulcem	PMMA; Palacos	Overall
Change in SSA
Fused levels; Nonfused levels; ^#𝑃	−5.2^∘±4.4^∘; −2.1^∘±3.9^∘; 0.030^∗	−2.2^∘±7.4^∘; −3.0^∘±3.8^∘; 0.662	−1.4^∘±3.4^∘; −0.5^∘±6.0^∘; 0.605	−3.3^∘±5.7^∘; −1.8^∘±4.6^∘; 0.133
Subsidence (mm)
Fused levels; Nonfused levels; ^#𝑃	2.7±2.7; 1.7±1.7; 0.152	3.2±3.2; 2.2±1.8; 0.204	3.1±2.1; 2.3±2.6; 0.336	3.0±2.8; 2.1±2.1; 0.055
VAS
Fused patients; Nonfused patients; ^#𝑃	2.9; 3.1; 0.667	3.4; 3.8; 0.626	2.0; 3.3; 0.168	2.8; 3.4; 0.216
NDI
Fused patients; Nonfused patients; ^#𝑃	24.1; 28.0; 0.439	32.7; 37.0; 0.512	19.9; 28.6; 0.140	26.0; 31.2; 0.136
SF-36; Physical function
Fused patients; Nonfused patients; ^#𝑃	66.4; 72.1; 0.443	56.4; 42.2; 0.160	63.0; 63.3; 0.974	62.2; 58.9; 0.538
SF-36; Physical component summary
Fused patients; Nonfused patients; ^#𝑃	39.6; 39.7; 0.971	37.7; 28.5; 0.024^∗	37.8; 40.7; 0.489	38.5; 36.3; 0.349

The table shows means (with standard deviations) of change in segmental sagittal alignment, subsidence, pain level, and functional outcome according to the fusion status.
SSA: segmental sagittal alignment.
VAS: Visual Analog Scale.
NDI: Neck Disability Index.
SF-36: Short Form 36 Health Survey.
^#Student's 𝑡-test (two-tailed).
^∗𝑃<0.05.