|Year : 2016 | Volume
| Issue : 4 | Page : 839--840
Department of Neurological Sciences, Christian Medical College Hospital, Vellore - 632 004, Tamil Nadu, India
Department of Neurological Sciences, Christian Medical College Hospital, Vellore - 632 004, Tamil Nadu
|How to cite this article:|
Rajshekhar V. Author's reply.Neurol India 2016;64:839-840
|How to cite this URL:|
Rajshekhar V. Author's reply. Neurol India [serial online] 2016 [cited 2022 Aug 13 ];64:839-840
Available from: https://www.neurologyindia.com/text.asp?2016/64/4/839/185376
I thank Dr. Goel for his interest in our article on 3-level corpectomy in patients with cervical spondylotic myelopathy (CSM) and ossified posterior longitudinal ligament (OPLL) published recently in the Journal.
Dr. Goel's hypothesis on the pathogenesis of spondylotic disease and OPLL rests exclusively on “instability” due to degenerative changes in the facet joints. Hence, his proposed management strategy involves stabilizing the cervical spine using spacers placed in the facet joints without any decompression. He cannot, however, deny that the disc and the ligaments such as the posterior longitudinal ligament (PLL) also participate in the degenerative process and contribute to cord compression. Therefore, the two main points of contention with respect to the pathogenesis of CSM are whether the degenerative process started in the facet joints or the discs and PLL, and whether instability alone (dynamic compression) or both static and dynamic compression play a role.
The first argument is more of “chicken or egg” situation and it is almost impossible to prove whether the degeneration starts initially in the facet joints or the discs and subsequently involves the other. The second argument, to my mind, is a settled issue. Dynamic compression due to instability as a cause of CSM has a long history. As far back as 1954, Pallis et al., documented the contribution of instability, recognized on plain radiographs as “subluxation” of the bodies, to the causation of CSM. Nurick, in his landmark article in 1972, corroborated their findings by reporting that the proportion of patients with subluxation was higher in the poorer grades than in those in the better grades. In other words, dynamic compression was recognized by these early workers to be an important component for the pathogenesis of CSM.
Flowing from these early observations of “instability” in patients with CSM and experimental evidence, “stabilization” of the cervical spine was suggested as a necessary component of the surgical management, although, almost always with decompression of the neural elements.,, In the case of conservative therapy, however, immobilization of the neck alone in a cervical orthosis is a valid option and has been shown to be associated with improvement. I do not agree that fusion following decompression surgeries such as central corpectomy is only done because of the destabilizing effects of the corpectomy; it is also done as a method for addressing any existing instability in the spine caused by the spondylotic process. In recent years, even proponents of a posterior decompression surgery such as a laminectomy have incorporated fusion into the procedure.
The management of CSM or OPLL is generally accepted to consist of both decompression and stabilization. It would not be prudent to ignore the obvious “static” compression seen on imaging and rely solely on immobilization of the spine to achieve good outcomes. The good outcomes reported with ventral decompression and fusion reported by different surgeons from across the world over the last five decades stands as testimony to its efficacy., Currently, I believe, as do most neurosurgeons, that some form of decompressive surgery is the standard of care for patients with significant myelopathy due to CSM or OPLL.
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Conflicts of interest
There are no conflicts of interest.
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