Cervical range of motion and alignment after laminoplasty preserving or reattaching the semispinalis cervicis inserted into axis.
METHODS
A radiographic study in 111 patients using radiographs was conducted.


OBJECTIVE
To clarify whether the modified laminoplasty with C3 laminectomy preserving the semispinalis cervicis (SSC) inserted into C2 could maintain the postopertive range of motion (ROM) and sagittal alignment compared with conventional C3-C7 laminoplasty reattaching the muscle to C2.


BACKGROUND
Intraoperative injury of the SSC is relevant to the significant loss of ROM and the malalignment after laminoplasty. To expose the C3 lamina, however, the SSC inserted into C2 could not be preserved in conventional C3-C7 laminoplasty.


METHODS
The ROM and sagittal alignment of 70 patients (group A) (52 men, 18 women, mean age 59 y, mean follow-up period 1 y and 7 mo) with C4-C7 laminoplasty with C3 laminectomy were compared with those of 41 patients (group B) (28 men, 13 women, mean age 59 y, mean follow-up period 2 y and 6 mo) with C3-C7 laminoplasty using radiographs of the cervical spine.


RESULTS
Regarding C2-C7 ROM, the postoperative ROM was larger (P=0.003) and the decrease rate of ROM was smaller (P=0.0006), and decreased ROM in extension was smaller (P<0.0001) in group A. Regarding O-C2 ROM, the increased ROM was smaller (P=0.043) and increased ROM in extension was smaller (P=0.001) in group A. Regarding O-C7 ROM, the postoperative ROM was larger (P=0.029) in group A. Regarding the cervical alignment, the increased lordotic angle at O-C2 was smaller (P=0.046) in group A.


CONCLUSIONS
This modified laminoplasty preserving the SSC inserted into C2 is an effective procedure for maintaining postoperative ROM, especially in extension, and sagittal alignment of the upper cervical spine well.
Department of Orthopaedic Surgery, Hirosaki University School of Medicine, Japan. naritake03@ybb.ne.jp
Kazunari
K
Takeuchi
Toru
T
Yokoyama
Atsushi
A
Ono
Takuya
T
Numasawa
Kanichiro
K
Wada
Gentaro
G
Kumagai
Junji
J
Ito
Kazumasa
K
Ueyama
Satoshi
S
Toh
D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007796:Laminectomy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009334:Neck Muscles / Q000601:surgery*; D011859:Radiography; D016059:Range of Motion, Articular; D016896:Treatment Outcome