A systematic review of surgical procedures on thoracic myelopathy.
PURPOSE
The surgical treatment of thoracic myelopathy is still controversial and also a challenge for spine surgeons. Therefore, the objective of this study was to review the related literature on the surgical treatment of thoracic myelopathy and try to define treatment guidelines for spine surgeons on thoracic myelopathy.


METHODS
Relevant literatures were searched based on the PubMed, EMBASE, and Cochrane Library between January 2008 and December 2018. Some data on the characteristics of patients were extracted, including number of patients, mean age, surgical procedures, blood loss, complications, and pre-/post-operation modified JOA score. Recovery rate was used to assess the effect of surgery outcome, and the safety was evaluated by blood loss and incidence of complications.


RESULTS
Thirty-five studies met the inclusion criteria and were retrieved. A total of 2183 patients were included in our systematic review, with the average age of 55.2 years. There were 69.8% patients diagnosed as ossification of ligamentum flavum (OLF), 20.0% as ossification of posterior longitudinal ligament (OPLL), 9.3% as disk herniation (DH), and 0.9% as others including diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS). The volume of blood loss was more in the treatment of circumferential decompression (CD) than posterior decompression (PD), and the incidence of complications was higher in CD (P < 0.05). The volume of blood loss in minimally invasive surgery (MIS) was lowest and the incidence of complications was 19.2%. Post-operation recovery rate was 0.49 in PD, 0.35 in CD, and 0.29 in MIS while the recovery rate was 0.54 in PD, 0.55 in CD, and 0.49 in MIS at the last follow-up. When focusing on the OLF specifically, incidence of complications in PD was much lower than CD, with less blood loss and higher recovery rate. Focusing on the OPLL specifically, incidence of complications in PD was much lower than CD, with less blood loss while there was no statistical difference in recovery rate between these two methods.


CONCLUSIONS
This systematic review showed that posterior decompression for thoracic myelopathy is safer and better than circumferential decompression according to the complication rate and surgical outcome. And we should also consider the location of compression before the operation.
['Zhu|Shiqi|S|', 'Wang|Yu|Y|', 'Yin|Peng|P|', 'Su|Qingjun|Q|http://orcid.org/0000-0001-9563-138X']
D016063:Blood Loss, Surgical D005260:Female D006801:Humans D008297:Male D017887:Ossification of Posterior Longitudinal Ligament D011183:Postoperative Complications D017410:Practice Guidelines as Topic D013118:Spinal Cord Diseases D013130:Spinal Stenosis D013904:Thoracic Vertebrae D016896:Treatment Outcome
Ossification of ligamentum flavum (OLF) Ossification of posterior longitudinal ligament (OPLL) Thoracic myelopathy (TM) Thoracic spine decompression Thoracic spine stenosis (TSS)