Cervical spondylotic myelopathy is a degenerative spinal disease which may lead to significant clinical morbidity. The onset of symptoms is usually insidious, with long periods of fixed disability and episodic worsening events. Regarding the pathophysiology of CSM, the repeated injuries to the spinal cord are caused by both static and dynamic mechanical factors. The combination of these factors affects the spinal cord basically through both direct trauma and ischemia. Regarding the diagnosis, both static and dynamics X-rays, as well as magnetic resonance imaging are important for preoperative evaluation as well as individualizing surgical planning. The choice of the most appropriate technique is affected by patient's clinical condition radiologic findings, as well as surgeon's experience. In opposition to the old belief that patients presenting mild myelopathy should be treated conservatively, there has progressively been amount of evidence indicating that the clinical course of this disease is progressive deterioration and that early surgical intervention improves long-term functional recovery and neurological prognosis. 1. Introduction Cervical spondylosis is the most common nontraumatic cause of myelopathy in the cervical spine [1]. Different from the majority of the other spinal problems in which the clinical treatment is usually the first option, early surgery is a key point to interfere in the natural history of cervical spondylotic myelopathy (CSM) and improve the neurological prognosis. In fact, there is strong evidence showing that surgery within one year from onset of symptoms strongly improves prognosis in CSM [1–3]. Nevertheless, the diagnosis of CSM can be difficult because the signs and symptoms can vary widely among the population. Besides, onset of symptoms is usually insidious, with long periods of fixed disability and episodic worsening events. Some findings that can commonly appear are gait spasticity, followed by upper extremity numbness and loss of fine motor control in the hands [2, 3]. Although it is generally agreed that surgical intervention positively impacts the prognosis of CSM, the decision algorithm for the selection of the most appropriate surgical technique is complex. In fact, the choice between a ventral or a dorsal approach depends on several factors such as the relative location of the primary compression (dorsal × ventral) and the alignment of the cervical spine (lordosis × kyphosis), as well as patient-specific spinal biomechanics [2–4]. 2. Pathophysiology CSM has been first defined by Brain et al. in 1952 [2]. The
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