Results Summary

What was the research about?

Cervical spondylotic myelopathy, or CSM, happens when the spinal cord becomes compressed, or squeezed, as people age. CSM can cause neck pain, loss of balance, and weakness in the hands and arms.

In this study, the research team compared types of surgery to treat CSM:

  • Ventral decompression and fusion: A surgeon stabilizes the spine from the front of the neck.
  • Dorsal decompression: A surgeon stabilizes the spine from the back of the neck. A surgeon can do two types of dorsal surgery. One type is a technique called fusion. The second type is called dorsal laminoplasty.

What were the results?

One year after surgery, the research team found no difference in physical function for patients with ventral or dorsal surgery. Patients with ventral surgery had more problems swallowing than patients with dorsal surgery.

Compared with the other two types of surgery, patients with dorsal laminoplasty had better physical function and fewer problems from surgery. They were also less likely to report using opioids for pain, having imaging tests, and having ongoing physical therapy. Patients didn’t differ in spinal function, quality of life, ability to return to work, or number of doctor visits. But the patients with dorsal laminoplasty may have differed from most patients with CSM. Also, only 28 patients had dorsal laminoplasty. As a result, it’s hard to say that these patients’ results were due to the type of surgery.

Who was in the study?

The study included 163 patients ages 45–80 who needed surgery for CSM. Of these, 85 percent were white, 8 percent were black, 3 percent were Asian, 2 percent were American Indian, and 1 percent were another race; 4 percent were Hispanic. The average age was 62, and 51 percent were women. Among patients, 66 had ventral decompression and fusion, 69 had dorsal decompression and fusion, and 28 had dorsal laminoplasty.

What did the research team do?

The research team assigned patients by chance to receive either ventral or dorsal surgery. For patients assigned to have dorsal surgery, their surgeons chose whether to perform dorsal decompression and fusion or dorsal laminoplasty.

One year after surgery, patients completed surveys about their physical and spinal cord function and quality of life. The research team also asked patients to keep a diary of their return to work and healthcare use. Patients tracked imaging tests, use of opioids for pain, and visits with physical therapists and doctors.

Patients, surgeons, and health insurers provided input on the study.

What were the limits of the study?

Because surgeons chose which type of dorsal surgery to perform, patients’ results may be due to reasons other than surgery type. Most patients in the study were white. Results may differ for patients of other races.

Future research could compare the three types of surgery with a more diverse group of patients who are assigned by chance.

How can people use the results?

Patients with CSM and their doctors can use the results when considering type of surgery for CSM.

Final Research Report

View this project's final research report.

Journal Citations

Article Highlight: Cervical spondylotic myelopathy, or CSM, occurs when the spinal cord becomes compressed as people age and is the most common cause of spinal cord dysfunction worldwide. This PCORI-funded study — conducted by a team at the Lahey Clinic in Massachusetts — examined patient-reported outcomes one year after surgery among patients who received any of the three common surgical treatments for CSM. As reported in JAMA, compared with the other two types of surgery, patients with dorsal laminoplasty had better physical function and fewer problems from surgery. They were also less likely to report using opioids for pain, having imaging tests, and having ongoing physical therapy.

Peer-Review Summary

Peer review of PCORI-funded research helps make sure the report presents complete, balanced, and useful information about the research. It also assesses how the project addressed PCORI’s Methodology Standards. During peer review, experts read a draft report of the research and provide comments about the report. These experts may include a scientist focused on the research topic, a specialist in research methods, a patient or caregiver, and a healthcare professional. These reviewers cannot have conflicts of interest with the study.

The peer reviewers point out where the draft report may need revision. For example, they may suggest ways to improve descriptions of the conduct of the study or to clarify the connection between results and conclusions. Sometimes, awardees revise their draft reports twice or more to address all of the reviewers’ comments. 

Peer reviewers commented and the researchers made changes or provided responses. Those comments and responses included the following:

  • The reviewers questioned the importance of the study’s comparison groups of patients undergoing surgery for cervical spondylotic myelopathy (CSM), noting that there is general agreement among surgeons that the choice between anterior and posterior surgery options depends on whether the lesion is more or less than three segments long. The researchers acknowledged this general practice but noted that their study demonstrated that there was no difference between anterior and posterior surgical approaches at the same levels of stenosis. The researcher agreed with the reviewers, however, that the best next step for this research would be a randomized trial comparing laminoplasty with posterior laminectomy and fusion.
  • The reviewers asked why the researchers chose to enroll patients aged 45 to 80, noting that older age correlates with an increased risk for spine surgery complications. The researchers agreed that including older patients may have increased the number of complications identified in the study. However, the researchers said they included patients up to age 80 so as to be representative of the spectrum of patients who undergo surgery for CSM in the United States, including the increasing number of older patients undergoing such surgery.
  • The reviewers suggested more prominent discussion of swallowing difficulties as a complication found in a subset of patients. The researchers agreed that difficulty swallowing would be a concerning complication for patients and their doctors to know about but explained that the swallowing difficulty that the researchers observed as a complication in a subset of patients resolved by one year after surgery, so the researchers did not report it as a major complication.
  • The reviewers suggested that the researchers explain the low rate of minority participation in the study and asked whether that low rate reflected wider difficulty for minorities in obtaining access to CSM surgery. The researchers said they tried to recruit minorities and added urban study sites to try to increase minority participation, but the centers that perform large numbers of CSM surgeries serve mostly Caucasian people. The researchers noted that minorities should be included in studies of CSM and recommended that future studies include more minorities in the study population than they were able to accomplish in the current study. 

Conflict of Interest Disclosures

Project Information

Zoher Ghogawala, MD
Lahey Clinic, Inc.
Cervical Spondylotic Myelopathy Surgical Trial (CSM-S Trial)

Key Dates

September 2013
September 2020

Study Registration Information


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Last updated: April 12, 2024