Rapid progressive clinical deterioration of cervical spondylotic myelopathy

Abstract

Study Design: Retrospective clinical study. Objective: To elucidate the pathophysiology of rapid progressive clinical deterioration following the onset of cervical myelopathy. Setting: Spinal Injuries Center, Fukuoka, Japan. Methods: A total of 43 cervical spondylotic myelopathy (CSM) patients were treated surgically by a senior surgeon. All patients showed intramedullary intensity changes on magnetic resonance (MR) imaging. Overall, eight patients suffered rapid progressive clinical deterioration; four of them had obvious anamnesis of minor trauma. We assessed the responsible injured segment by MR T2-weighted images. Clinical instabilities at the focal segment were evaluated using functional sagittal plain radiographs. Neurological evaluations were performed preoperatively and at 12 months postoperatively using American Spinal Injury Association (ASIA) motor scores and Japanese Orthopaedic Association (JOA) scores for cervical myelopathy. Intraoperatively, we evaluated the presence of adhesive scar tissue on the dura mater at the focal segment. Results: The responsible injured segment was C3-4 in 75% of the rapid progressive (rp)-CSM and in 28.57% of the conventional CSM subjects. One with rp-CSM showed sagittal translational segmental instability. Preoperative ASIA motor scores and JOA scores in the rp-CSM were significantly lower than those in the conventional CSM subjects. Postoperative ASIA motor scores between the subjects showed no significant differences; however, postoperative JOA scores in the rp-CSM subjects were significantly lower. Moreover, an epidural membrane was observed in 62.5% of rp-CSM and 11.4% of conventional CSM subjects. Conclusions: We hypothesized that the pathophysiology of rp-CSM might be additional cervical cord disorder following the onset of cervical myelopathy. Early decompression surgery is recommended in such patients. INTRODUCTIONThe etiologies of cervical spondylotic myelopathy (CSM) include spinal cord compression, dynamic factors and ischemia of the spinal cord. Several anatomical structures in the cervical motion segment can be involved in cervical spinal cord compression. The spondylotic changes in anterior structures, such as bulging, ossified or herniated discs, as well as anterior osteophytic spurs are generally responsible for cord compression in CSM. Disorders in posterior structures, such as hypertrophy, or rarely, ossification/calcification of the ligamentum flavum (CLF) or facet joints may also contribute to cord compression. Compression of the spinal cord within a narrow spinal canal is believed to cause neural injury and ischemia. The cord and its vascular supply have the ability to adapt to a chronic, slowly progressing compression; therefore, dynamic compression may be more important than static compression in the development of myelopathy symptoms. Patients with canal stenosis also have limited cord excursion, and spinal column motion may increase the strain and shear forces on the spinal cord. 1 CSM is a relatively slowly progressive disorder. However, we r...

Signal intensity ratio on magnetic resonance imaging as a prognostic factor in patients with cervical compressive myelopathy

“…[15,20,21] For patients with mild myelopathy, a progressive course with intractable pain or angular-edged deformity should be considered an indicator for surgery. [22–24] A Cochrane review on the role of surgery in mild cervical myelopathy concluded that a surgical operation impacts pain, weakness, and sensory loss, compared to conservative management; however, there is little or no difference in the long term. [25,26] …”

Venous hypertensive myelopathy associated with cervical spondylosis

“…The typical course of CSM is a relatively slow, progressive, and stepwise deterioration in neurologic function with stable plateau periods [1,2]. Rapid progress of neurologic deterioration of patients with CSM is fairly rare, and most cases are associated with minor trauma or segmental instability [3]. Even in such cases, signal changes are not often observed on MRI.…”

Outcome and predictive factors in rapid progressive cervical spondylotic myelopathy: A retrospective case-control study

“…The prognosis of patients with rapid progressive CSM is quite different among previous studies, Morishita reported that the preoperative JOA score is 5.4 and 9.6 at 1 year after surgery, which were signi cantly lower than in chronic CSM which were 10.1 and 12.9, respectively, and they concluded that prognosis of rp-CSM group was inferior than those in c-CSM group [3]. However, in the study of Takasawa [4] , JOA score was 5.7 preoperative and 12.9 after one year surgery (improvement rate was 64.5%) in rp-CSM group and 10.1 preoperative and 12.8 after one year surgery (improvement rate was 40.7%) in c-CSM, they reached a conclusion that patients with rp-CSM can get better recovery than those in c-CSM.…”

“…The patients were divided into rp-CSM group and c-CSM group according to the rp-CSM de ned by Morishita [3] and categorization of mJOA described by Fehlings [10]. In brief, rp-CSM means that CSM patients develop rapid and severe neurological dysfunction without history of trauma within the rst month after diagnosis, and preoperative mJOA score was from 0-11.…”

“…Previous studies have shown that 82% and 56% of CSM patients will not experience severe neurological deterioration 5 years and 10 years after systematic conservative treatment [2]. However, neurological function of some CSM patients develop to severe dysfunction (such as unable to button shirt or walk) in a very short time without any trauma, which called in previous studies as rapid progressive CSM (rp-CSM) [3][4][5].…”