====== C2-7 Cobb Angle ======


{{ ::c2_c7_angle.jpg?400|}}


[[T1 slope]] minus [[C2 C7 angle]] lordosis (TS-CL) and [[cervical sagittal alignment]] reportedly affect health-related quality-of-life (HRQOL) scores following multilevel posterior cervical fusion surgery.

see also [[C2-C7 sagittal vertical axis]]

see also [[T1 slope]]

see also [[C7 slope]]

see also [[Neck tilt]]

[[Expandable cage]]s are frequently used to reconstruct the anterior [[spinal column]] after a [[corpectomy]]. In a [[retrospective]] study, Pojskic et al. evaluated the perioperative [[advantage]]s and [[disadvantage]]s of corpectomy [[reconstruction]] with an expandable cage.

Eighty-six patients (45 male and 41 female patients, medium age of 61.3 years) were treated with an expandable [[cervical titanium cage]] for a variety of [[indication]]s from January 2012 to December 2019 and analyzed retrospectively. The mean follow-up was 30.7 months. Outcome was measured by clinical examination and [[visual analogue scale]] ([[VAS]]); [[myelopathy]] was classified according to the EMS ([[European Myelopathy Score]]) and gait disturbances with the [[Nurick scale]]. Radiographic analysis comprised measurement of [[fusion]], [[subsidence]] and the [[C2-C7 angle]]. 

Indications included [[spinal canal stenosis]] with [[myelopathy]] (46 or 53.5%), [[metastases]] (24 or 27.9%), [[spondylodiscitis]] (12 or 14%), and [[fracture]] (4 or 4.6%). In 39 patients (45.3%), additional dorsal [[stabilization]] (360° fusion) was performed. In 13 patients, [[hardware failure]] occurred, and in 8 patients, [[adjacent segment disease]] occurred. Improvement of pain symptoms, [[myelopathy]], and [[gait]] following surgery were statistically significant (p < 0.05), with a medium preoperative [[VAS]] of 8, a postoperative score of 3.2, and medium EMS scores of 11.3 preoperatively vs. 14.3 postoperatively. Radiographic analysis showed successful fusion in 74 patients (86%). As shown in previous studies, correction of the C2-C7 angle did not correlate with improvement of neurological symptoms. 

The results show that [[expandable titanium cage]]s are a safe and useful tool in anterior cervical corpectomies for providing adequate anterior column support and stability
((Pojskic M, Saβ B, Nimsky C, Carl B. Application of an Expandable Cage for Reconstruction of the Cervical Spine in a Consecutive Series of Eighty-Six Patients. Medicina (Kaunas). 2020 Nov 25;56(12):E642. doi: 10.3390/medicina56120642. PMID: 33255605.)).
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Design variations of expandable cages for [[vertebral body replacement]] do not show any significant effect on the biomechanical results. There was no significant difference found, between the biomechanical properties of expandable and non-expandable cages. After corporectomy, isolated implantation of expandable cages plus anterior plating was not able to restore normal stability of the motion segment. As a consequence, isolated anterior stabilization using cages plus LCDCP should not be used for vertebral body replacement in the thoraco-lumbar spine
((Khodadadyan-Klostermann C, Schaefer J, Schleicher P, Pflugmacher R, Eindorf T,
Haas NP, Kandziora F. [Expandable cages: biomechanical comparison of different
cages for ventral spondylodesis in the thoracolumbar spine]. Chirurg. 2004
Jul;75(7):694-701. German. PubMed PMID: 15258751.
)).