Although the interaction between chronic pain and physical functioning is a well-accepted
paradigm, objective data on how pain affects individuals' daily life is scanty. Most data
are based on patient questionnaires. The purpose of this study is to objectively assess
the activity of daily living in chronic pain patients treated with spinal cord
stimulation (SCS).
Indication: Chronic pain in the low-back and/or leg(s) due to failed back surgery
syndrome
Study Design: Prospective, open-label, multi-center, observational, study.
Sample Size: 50 patients receiving an Intellis neurostimulator for treatment with SCS.
Study Centers: Up to 10 sites in Europe
Objectives:
Utilize an existing neurostimulator-based data diary to measure gross daily activity
in patients with chronic pain
Test the usefulness of this data diary as a tool for objective evaluation of SCS
efficacy on chronic pain.
Investigate how the collected objective data relates to the subjective experience of
the patient when evaluating the effects of SCS.
Materials/Methods:
Patients diagnosed with failed back surgery syndrome (FBSS) with chronic back and leg
pain that have been evaluated as candidates for SCS will be included.
Gross daily activity is recorded using the Intellis neurostimulator (Medtronic Inc.)
which contains a diary (AdaptiveStim™ Diary) that continuously stores data of seven
different body positions: upright, upright mobile, recline and 4 lying positions.
Recordings are performed for 4 weeks before the SCS trial (baseline) using an external
Intellis device adhered to the skin of the abdomen and thereafter, in patients who
responded to SCS during the SCS-trial period, utilizing the permanent Intellis implanted
subcutaneously at the same site. Data will be extracted from the data diary at 3, 6 and
12 months after implantation of the SCS system and compared with changes in pain, quality
of life and sleep as assessed by patient self-report questionnaires using validated
tools.
Study Duration:
The estimated duration of the study from first enrolment to final report is 24 months,
including a 10 months enrolment period. The estimated duration of a subject's
participation in the study is approximately 12 months. Interim analyses will be performed
after 3 and 6 months follow up.
BACKGROUND The use of spinal cord stimulation (SCS) for pain control has already a
history of more than 50 years. During the last decades many articles have been published,
indicating the effectiveness and safety of SCS in the pain management of chronic
neuropathic pain, and in particular in patients with chronic back and leg pain due to
persisting, new or recurrent pain after spinal surgery, so called failed back surgery
syndrome (FBSS).1 In this patient group the interaction between chronic pain and physical
functioning is a well-accepted paradigm, although objective data that shows how pain
affects individuals' daily life is scanty. Correlation between reduction in pain
intensity and sustained improvement in physical activity has previously been demonstrated
using kinematical sensors.2.3 In SCS, most outcome data are based on patient
questionnaires. The lack of tools for objective evaluation of the effects of SCS on
chronic pain has posed a barrier for providing solid proof of the therapy. Currently,
however, SCS-devices with an accelerator included are available on the market. The
position orientation data provided by the neurostimulator therefore gives new
possibilities for objective measurement of gross activity in daily life.
In an earlier single center pilot study with the first implantable neurostimulator with
an accelerometer the potential of objective outcome measurements was explored in six
patients with FBSS.4 A positive correlation between decrease in pain and increase in time
spent in upright position has been demonstrated by the preliminary pilot study utilizing
this neurostimulator in which position and upright/upright mobile changes were recorded
based on 24-hour cycles. However, not all patients that experience good pain relief
showed an increased activity level depending on which position that is painful.
With the new neurostimulator (Intellis), position changes and level of activity are
recorded on an hour by hour basis, which makes it possible to differentiate between day
and night activity. The goal of the current study is to repeat the pilot study on
objective outcomes with the newly available neurostimulator with inbuilt accelerometer
using a prospective, open-label, observational study design.
OBJECTIVES
Utilize an existing neurostimulator-based data diary to measure gross daily activity
in patients with CBLP.
Test the usefulness of this data diary as a tool for objective evaluation of SCS
efficacy on CBLP.
Investigate how the collected objective data relates to the subjective experience of
the patient when evaluating the effects of SCS.