Myoarchitectonic spinolaminoplasty: efficacy in reconstituting the cervical musculature and preserving biomechanical function.
OBJECTIVE
Laminoplasty has been used to expand the cervical spinal canal, based on the belief that reconstruction of the laminae preserves musculoskeletal function. The true efficacy of laminoplasty for maintaining spinal alignment, stability, and flexibility, however, remains to be proven. The authors have developed a new method, myoarchitectonic spinolaminoplasty (MSLP), which preserves all of the nuchal muscles and reconstitutes all of the musculoskeletal couplings to the posterior elements of the vertebrae. The details of this technique are described, and the efficacy of the technique in conserving muscle volume, alignment, and motion, as well as in preventing postoperative musculoskeletal discomfort, is assessed.


METHODS
The authors' previous midline-splitting laminoplasty procedure, which utilized a hydroxyapatite (HA) implant as a substitute for the spinous process, was improved. Detachment of the muscles is avoided with this new technique by cutting inside the spinous process. The bone-muscle flaps are affixed to the HA spinous process. Radiographs, computed tomography scans, and neurological evaluations obtained at the 1-year follow-up in the groups of consecutive patients assessed immediately prior to and after the modification of the previous technique (the control and the MSLP groups, respectively) were analyzed and compared.


RESULTS
The HA bone constructs became integrated due to osteoconduction. The cross-sectional area of the semispinalis capitis, semispinalis cervicis, and multifidus muscles remained significantly larger in the MSLP group. Slight attenuation in lordosis was observed in the control group, but was prevented in the MSLP group. Range of motion was somewhat restricted in the MSLP group, but the incidence of neck pain and shoulder strain was significantly reduced.


CONCLUSIONS
The new MSLP method was effective in preserving the volume and functions of the nuchal musculature and helping to minimize postoperative musculoskeletal complaints.
Kim
Phyo
P
Department of Neurosurgery, Dokkyo University School of Medicine, Tochighi, Japan. kim@dokkyomed.ac.jp
Murata
Hidetoshi
H
Kurokawa
Ryu
R
Takaishi
Yoshiyuki
Y
Asakuno
Keizo
K
Kawamoto
Toshiki
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001672:Biocompatible Materials; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D017886:Durapatite; D005260:Female; D006801:Humans; D007796:Laminectomy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009133:Muscular Atrophy / Q000000981:diagnostic imaging; D009334:Neck Muscles / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D010147:Pain Measurement; D010149:Postoperative Pain; D016059:Range of Motion, Articular; D019651:Plastic Surgery Procedures; D013130:Spinal Stenosis / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D001672:Biocompatible Materials; D017886:Durapatite