The Change of Range of Motion at Anterior Compression of the Cervical Cord after Laminoplasty in Patients with Cervical Spondylotic Myelopathy

Abstract

ObjectiveDegenerative diseases of the spine, such as cervical spondylotic myelopathy (CSM), are increasing among the old age population, and surgical treatment of CSM is becoming more and more common. The aim of this study was to investigate how functional recovery can be influenced by anterior compression of the spinal cord (ACS) after laminoplasty for treatment of patients with CSM.MethodsWe retrospectively analyzed 32 patients admitted to Ewha Womans Mok-Dong Hospital with CSM who underwent open-door laminoplasty from January 2012 to December 2014. We divided patients into 2 groups according to whether ACS was or not preoperatively. Each group was analyzed clinical and radiological parameters which were Japanese Orthopedic Association (JOA) scores and its recovery rate, sagittal alignment and range of motion (ROM).ResultsThe mean duration of symptom was 11.2 months (range, 6-22 months). A significant difference in recovery rate of the total JOA score was shown between the 2 groups, especially upper extremity motor function. No difference in preoperative JOA score between the 2 groups, but recovery rate of each group was 20.05%±18.1%, 32.21%±25.4%, statistically significant (p<0.005). Upper motor and sensory function was not significantly different in the 2 groups. Preoperative, postoperative and preservation of ROM was 44.3°±10.1°, 41.8°±15.7°, 87.9%±35.4% each at ACS (-) group. A significant difference in postoperative ROM was identified between ACS (-) and ACS (+) group. Postoperative anterior compression of the spinal cord was recognized 14 cases which were classified from its causes.Conclusion Cervical ROM decreased significantly after laminoplasty, but 85.3% of the preoperative ROM was preserved. The postoperative reduction of ROM in group with anterior compression of spinal cord was identified.

Cervical Spondylotic Myelopathy: Pathophysiology and Surgical Approaches

“…However, they did not describe the preservation of the muscle attachment at the C2 level in the technique. Conversely, Cho [37] and Sakaura et al [40] preserved the C2 muscle attachment in their technique, and this resulted in lesser loss of cervical lordosis than that reported by Uehara et al [34]. Interestingly, Su et al [36] reported lesser loss of cervical lordosis after performing C3-C6 laminoplasty without preserving the C2 muscle attachment.…”

“…Technique with preservation of C2 and C7 muscle attachment may reduce the risk of cervical ROM loss. Cho [37] demonstrated that they only preserved C2 muscle attachment; their study showed the lowest loss of cervical ROM. However, in their study, above 70% of their technique did not involve C7 in the extent of laminoplasty.…”

“…Several studies showed that laminoplasty reduced cervical ROM in various degrees [34,35,[37][38][39][40]. As shown in Table 2, it seems that the preservation of C2 and C7 muscle attachments have an important role in the preservation of cervical ROM postoperatively.…”

“…Most of these studies used the JOA score as a parameter of clinical outcome. They reported that laminoplasty provided significant enhancement of the JOA score in the short-term, mid-term, and long-term follow-up [34][35][36][37][38][39]. However, Sakaura et al [40] reported that the average JOA score was at its highest point in 12 months of follow-up and decreased slightly to 14.9 in the final follow-up.…”

“…Several studies reported that laminoplasty reduced the C2-C7 lordotic angle [34][35][36][37]. These studies used different laminoplasty methods to provide decompression of the spinal cord.…”