Biomechanical study of anterior cervical corpectomy and step-cut grafting with bioabsorbable screws fixation in cadaveric cervical spine model.
METHODS
An in vitro biomechanical study.


OBJECTIVE
To determine the initial stability of a novel construct in a 1-level cadaveric cervical spine model by comparing it with a conventional method.


BACKGROUND
Lots of endeavors have been made to enhance fusion rates and reduce complications in the anterior cervical spine procedure.


METHODS
There were 12 fresh human cadaveric cervical spines (C3-C7) randomly divided into 2 groups: group 1, 1-level corpectomy of C5 and step-cut grafting with bioabsorbable screw fixation (SCAS); and group 2, 1-level corpectomy of C5 and strut grafting with anterior plate fixation (SP). For each specimen, the intact underwent a flexibility test first, followed by the instrumented construct. Rotational angles of the C4-C6 segment were measured to study the immediate stability of anterior cervical corpectomy and SCAS, compared with the intact and anterior cervical corpectomy and SP.


RESULTS
Both anterior cervical corpectomy with SCAS and with SP significantly (P < 0.01) decreased the motions of C4-C6 in all 6 degrees of freedom after instrumentation. Compared with anterior cervical corpectomy and SP, anterior cervical corpectomy and SCAS had higher stability (P < 0.05) in extension, and comparable stability (P > 0.05) in flexion and axial rotation, but lower stability (P <or= 0.05) in lateral bending.


CONCLUSIONS
Anterior cervical corpectomy and SCAS, a novel method of anterior cervical spine decompression and reconstruction, was introduced. The in vitro biomechanical study showed that anterior cervical corpectomy and SCAS had sufficient immediate stability except for the lateral bending, compared with anterior cervical corpectomy and SP, in a 1-level cadaveric cervical spine model. However, an animal experimental in vivo evaluation of anterior cervical corpectomy and SCAS still has to be performed.
Zhang
Jian
J
Department of Orthopaedic Surgery, the 2nd Hospital of Xi'an Jiaotong University, PR China.
He
Xijing
X
Li
Haopeng
H
Wang
Dong
D
Zhao
Weidong
W
Xu
Jiehua
J
Lan
Binshang
B
Xu
Siyue
S
D020341:Absorbable Implants; D000328:Adult; D001696:Biomechanical Phenomena; D001863:Bone Screws; D016025:Bone Transplantation / Q000379:methods; D002102:Cadaver; D002574:Cervical Vertebrae / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007593:Joint Instability / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures; D013123:Spinal Fusion / Q000379:methods*