The rate of patients who came back for their six month examinations and
x-rays was 74% for the CervicalStim device group and 73% for the control
group. Patients who did not come back for scheduled examinations could not
be evaluated; thus their success or failure is not known. These unavailable
data could have a positive or negative effect on the overall success of this
study.
One hundred and twelve (112) patients reported a total of 157 adverse
(negative) effects for both groups combined at six months after surgery. There
was no significant (meaningful) difference in the total number of adverse
events or the number of patients reporting effects in the control group
and the CervicalStim device group nor in the numbers of patients in each
group who experienced an adverse event. The adverse effects that may be
experienced include: increased pain, numbness and tingling, headache,
migraines and nausea. These effects may or may not be directly related to the
use of the CervicalStim device.
Clinical success with regard to symptoms was evaluated by the following:
• no worsening in neurological function
• an improvement in pain
• no worsening in Neck Disability Index
Based on the criteria above, there was no major difference between the
control group and the CervicalStim device group in clinical success. An equal
number of patients in both groups showed an improvement in their clinical
condition after surgery, regardless of treatment.
Long-term x-ray information collected at 11 months after surgery or later
showed no meaningful difference in fusion rate between the CervicalStim
device treatment group and the control group who received routine care
alone.
The results of this study show that the use of the CervicalStim device is both
safe and effective in increasing the frequency of fusion by six months after
surgery in high-risk subjects having cervical fusion.
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