Expansive Open-Door Laminoplasty

Abstract

Until 1968, when Kirita [1] devised a sophisticated technique for extensive laminectomy in which the laminae were thinned and divided at the midline with a high-speed drill, both patients and surgeons had suffered from unpredictable results with conventional laminectomy. Being both safe and effective, Kirita’s technique brought remarkable progress in the surgical results of cervical compressive myelopathy. However, problems such as postoperative kyphosis, the vulnerability of the unprotected spinal cord, and the formation of a laminectomy membrane remained unsolved problems [2]. To address these problems, in 1973, Hattori and co-workers devised an expansive Z-laminoplasty in which the spinal canal was totally reconstructed with preservation of the posterior protective structures [3,4]. However, this technique did not gain widespread acceptance because it was too technically demanding as well as time-consuming. Hirabayashi et al. [5] modified Kirita’s method and decompressed the spinal cord by making bony gutters in both sides of the lamina followed by en-bloc resection of the laminae. The idea of open-door laminoplasty evolved when Hirabayashi [6] noted that pulsation of the dural tube occurred when he lifted one side of the laminae, indicating that sufficient decompression was obtained even before total resection of the laminae. He performed the first case of this procedure in 1977, and named it expansive open-door laminoplasty (ELAP; eelap). Since then, more than 500 patients have undergone this procedure at Keio University Hospital and affiliated hospitals with favorable results.