Exceptional Conditions for Favorable Neurological Recovery After Laminoplasty in Cases with Cervical Myelopathy Caused by K-line (−) Ossification of Posterior Longitudinal Ligament

• Published in: Spine (Philadelphia, Pa. 1976) Pa. 1976), 2021-08, Vol.46 (15), p.990-998
• Main Authors: Tsujimoto, Takeru, Endo, Tsutomu, Menjo, Yusuke, Kanayama, Masahiro, Oda, Itaru, Suda, Kota, Fujita, Ryo, Koike, Yoshinao, Hisada, Yuichiro, Iwasaki, Norimasa, Takahata, Masahiko
• Format: Article
• Language: English
• ISSN: 0362-2436; 1528-1159
• DOI: 10.1097/BRS.0000000000003945

A retrospective observational study. To clarify the exceptional conditions for a favorable neurological recovery after laminoplasty (LMP) for cervical myelopathy caused by K-line (-) ossification of the posterior longitudinal ligament (OPLL). The K-line-based classification of cervical OPLL was developed to predict insufficient neurological recovery after LMP. For patients with K-line (-) OPLL, LMP generally yields the least improvement because of inadequate decompression of the spinal cord; however, there are some exceptional cases wherein LMP promotes favorable neurological recoveries. We retrospectively reviewed the medical records of 106 consecutive patients who underwent LMP for cervical OPLL to determine the demographic data, radiographic findings, and neurological recoveries of the patients as assessed preoperatively and 2 years postoperatively by their Japanese Orthopedic Association (JOA) scores. The factors associated with favorable outcomes after LMP in patients with K-line (-) were then investigated. Of 106 total patients, 31 were classified as K-line (-), of whom 21 achieved the least neurological recovery after LMP (JOA recovery rate