Degenerative Cervical Myelopathy (DCM) is considered a progressive disease, but the rate of progression varies greatly from one person to the next. Some people remain only mildly affected for years, whereas others deteriorate rapidly. This rate or pattern of progression cannot currently be predicted accurately on an individual basis, which makes clinical decision-making (for example, establishing whether the benefits of surgery outweigh the risks) very difficult.
We are working to investigate this. One general principle has been demonstrated: the likelihood of further deterioration increases when the disease is more severe or actively progressing. International guidelines therefore state that for patients with moderate, severe or progressive disease, surgery is recommended; whereas, for patients with mild or stable cases, surgery is more of an option.
Our research is helping to shed light on this critical knowledge gap, to help people living with DCM and their healthcare professionals make more confident treatment decisions.
Myelopathy.org is working to understand the course of DCM. To learn more about the disease course, listen to our podcast, ‘The Natural History of DCM’. This podcast episode, and more in the same series, is based on our work with partners at AO Spine in which we brought people with DCM together with surgeons and allied healthcare specialists, to exchange knowledge and experience of the disease.
With your support, we can make further scientific advances.
Bumps in the Road: the Significance of Falls
People with cervical stenosis (narrowing of the spinal canal containing the spinal cord) are at risk of sudden deterioration due to a trauma such as a minor fall.
Why is this? Normally, the spinal cord moves within its canal in response to movements of the neck. However, when there is a narrowing of the canal, there is less room for the spinal cord to move. So, if a sudden force is applied to the neck, the spinal cord is more easily bruised and, in rare cases, this can lead to paralysis.
What is the chance of this happening? This is not well understood. In the latest review of evidence, it was estimated that an acute spinal cord injury (SCI) occurs in 13.8 per 1000 person years (or 4.8 per 1000 person years if your DCM is largely caused by Ossification of the Posterior Longitudinal Ligament). Person years are a method of combining patient follow-up data to represent risk: if 1000 patients were followed for 1 year, this would equal 1000 patient years. The occurrence of acute SCI in people with DCM is higher than in the healthy population (0.18 per 1000 person years), but remains a rare event . For example, one small study which followed 55 people with DCM found that whilst 1 in 5 experienced a fall, none experienced a worsening of their DCM as a result .
Once DCM surgery is completed, and cervical stenosis resolved, the risk of acute SCI following a trauma is believed to return to that of the healthy population.
In people with DCM who have not yet undergone surgery, healthcare professionals will often therefore advise caution in the activities they pursue; for example, avoiding sports with risks of high energy falls. Whilst this is logical, there is no evidence currently to provide recommendations on what type of activity modification should occur, if any.
Altering the DCM Disease Course
Once a Magnetic Resonance Imaging (MRI) scan shows that the spinal cord is compressed, approximately one-quarter of people will develop symptoms of DCM within four years. However, long periods can occur in which the disease remains stable, or the symptoms even improve.
The only treatment for DCM at present is surgery to relieve the pressure on the cord. This will stop or reduce further spinal cord damage, but the amount of recovery depends on the extent of the injury at the time of surgery.
A number of other treatments are in use to manage symptoms during this period, including physiotherapy; however, the evidence at this stage is uncertain . In our survey of the Myelopathy.org community, although half of people with DCM underwent physiotherapy as part of their non-operative management, only 1 in 5 people found it of any benefit.
International guidelines recommend that any such physiotherapy is performed as part of a structured surveillance programme overseen by a DCM specialist. The reason for this is firstly to detect in a timely manner any deterioration that may warrant surgery, but also, secondly, to ensure that therapies are not harmful. Historically, non-operative therapy for DCM included neck manipulation and neck traction. For the same reasons outlined above, these forceful movements of the neck, in people with cervical stenosis, risk causing an acute spinal cord injury.