New Test to Rate Severity of Cervical MyelopathyJapanese scientists have come up with a possible answer to a sticky problem. Patients with cervical myelopathy often have trouble walking because of damage to the spinal cord in the neck area. Finding a way to rate the severity of this condition can't rely on walking tests. Some patients can no longer walk, while others aren't safe doing a walking test. So, they devised and tested a sitting foot tapping test. This study presents the results of testing the new performance test!
Cervical myelopathy refers to any condition that causes degeneration, damage, or pathologic changes of the spinal cord in the cervical (neck) area. This condition can present with many different signs and symptoms. Difficulty walking has been mentioned. Limb spasticity (increased muscle tone) creates balance and walking problems. Other symptoms include neck and arm pain, electric shock sensation down the arms (called Lhermitte's sign), clumsiness of the hand(s), and difficulty with finger motion to name just a few.
Cervical myelopathy can develop as a result of a disc protrusion pressing on the spinal cord. Changes in the alignment of the vertebral bodies such as occur with spondylolisthesis can also contribute to this problem. In spondylolisthesis, there is a fracture and separation of one of the supporting columns of the vertebra. The affected vertebral body shifts forward over the bone below it. As this shift occurs, the spinal canal narrows between the two vertebrae and traction (pull) is placed on the spinal cord and spinal nerve roots.
Age-related factors are another category of factors leading to the development of myelopathy. For example, thickening and/or ossification (hardening) of the spinal ligaments within the spinal canal takes up space normally needed for the passage of the spinal cord. Degenerative changes of the vertebral bodies with bone spur formation and narrowing of the joint spaces compress the vertebral bodies. The result is a narrowing of the spinal canal. Any time the spinal canal space is decreased, the condition is called spinal stenosis. Spinal stenosis is a big reason why older adults develop cervical myelopathy.
So, why is a performance test really even needed for this group of patients? It provides a way to measure progression of the disease (i.e., is the patient getting worse and by how much?) and it gives a before and after measurement of results from surgery. Both of these measures are important when trying to provide evidence that a particular treatment is effective and should (or shouldn't) be recommended. Surgeons are also trying to decide when is the best time for patients with cervical myelopathy to have surgery. A test of this sort might help researchers pinpoint an answer.
The authors first proposed the triangle step test (TST) about 10 years ago. They've been testing it ever since and have some results for us now. They call it the triangle step test because of the way it's performed. No walking or upright balance is required. The patient sits in a chair and uses one foot to tap the three corners of a triangle (one corner after another). The number of steps or taps completed in 10 seconds is recorded. The test is repeated using the other foot.
By testing healthy adults (the control group), they were able to determine norms for comparison with the cervical myelopathy group. They also compared results using the triangle step test (TST) before and after surgery. Surgery was done to take pressure off the spinal cord and stabilize the spine. The TST showed rate of recovery after surgery. They tested the same patients using several other tests already available to check the validity of the TST. The other tests included the Nurick score, the finger grip and release (GRT) test, and the Japanese Orthopedic Association (JOA) score. Statistical analysis showed that the results of the TST correlated well (matched) the results of these other tests.
In summary, the triangle step test (TST) is a safe and simple test of lower extremity (leg) function. It can be used to test the severity of spinal cord compression in patients with cervical myelopathy. It takes less than one minute to complete and it doesn't require any equipment or cost anything. Even patients who can no longer stand up safely or walk can be tested using this tool. Those are all major advantages of this new performance test. The TST is also a sensitive measure of change from before to after surgery. In fact, it looks like the TST can be used to predict when surgery might be helpful. They found that patients who could complete 20 or more steps in 10 seconds would benefit from surgery.
The authors aren't quite ready to launch the test for general use with myelopathy patients. They say there are some things yet to consider. For example, many of the patients with age-related cervical myelopathy also have spinal stenosis of the lumbar spine or arthritis affecting the hips, knees, and lumbar spine. These comorbidities (additional problems) can cause pain and weakness, resulting in difficulty lifting the feet. Poor eyesight or dementia affecting the ability to follow directions can also affect the results of the TST. The authors plan to analyze how much each of these factors affects test results as their next research step.
Hisanori Mihara, MD, et al. A New Performance Test for Cervical Myelopathy. In Spine. January 2010. Vol. 35. No. 1. Pp. 32-35.
|*Disclaimer:* The information contained herein is compiled from a variety of sources. It may not be complete or timely. It does not cover all diseases, physical conditions, ailments or treatments. The information should NOT be used in place of visit with your healthcare provider, nor should you disregard the advice of your health care provider because of any information you read in this topic.|
|All content provided by eORTHOPOD® is a registered trademark of Medical Multimedia Group, L.L.C.. Content is the sole property of Medical Multimedia Group, LLC and used herein by permission.|