Unilateral instrumented fixation for cervical dumbbell tumors.
OBJECTIVE
The purpose of this study was to describe the radiological outcomes in patients with unilateral instrumented fixation for cervical dumbbell tumors.


METHODS
Fourteen consecutive individuals were included in the present study. We included Eden type II and III tumors in this cohort study and analyzed fixed segment fusion rates, screw failure with multiplanar reconstruction computed tomography (CT) scan radiographs and lateral radiographs with flexion-extension dynamic views, and immediate postoperative and last follow-up radiographs after surgery.


RESULTS
The mean follow-up was 105.4 months. There were six men and eight women ranging in age from 32 to 70 years (mean age, 48 years). Twenty pedicle screws (PSs) and 11 lateral mass screws (LMSs) were used in total. There were seven patients with only PSs, four with only LMSs, and three with PSs at C2 and LMSs at C3. PS misplacement occurred in three screws of insertions including two screws with grade 1 misplacement and one screw with grade 2 misplacement, and no grade 3 misplacement occurred. All screws breached the lateral wall with no apparent superior or inferior misplacement. None of the LMSs were misplaced. Fortunately, no complication could be directly attributed to screw insertion. Radiological evidence showed that all patients achieved successful fusion with no screw loosening or breakage. However, two patients who received only LMS fixation had degenerative spondylolisthesis at the upper fusion segment at the last follow-up.


CONCLUSIONS
Grade 2 PS misplacement occurred in one screw of insertions. Unilateral pedicle screw fixation for cervical dumbbell tumors is a useful surgical method that can successfully fuse vertebrae with good postoperative alignment.
Kei
K
Ando
Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65-Tsurumai, Nagoya City, Aichi 466-8550, Japan. si1222@b-star.jp.
Shiro
S
Imagama
Zenya
Z
Ito
Kazuyoshi
K
Kobayashi
Junichi
J
Ukai
Akio
A
Muramoto
Ryuichi
R
Shinjo
Tomohiro
T
Matsumoto
Hiroaki
H
Nakashima
Yoshihiro
Y
Nishida
Naoki
N
Ishiguro
D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016268:Internal Fixators; D008297:Male; D008875:Middle Aged; D011859:Radiography; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*