Clinical trial NCT03027947: Spinal Root and Spinal Cord Stimulation for Restoration of Function in Lower-Limb Amputees
Official title: Spinal Root and Spinal Cord Stimulation for Restoration of Function in Lower-Limb Amputees
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Traumatic Amputation of Lower Extremity
Phantom Limb Pain
Keywords: Phantom Limb Pain
Lower-Limb Amputation
Electrodes
Stimulation
Pain
Sensation
Lead sponsor: University of Pittsburgh
Sponsor class: OTHER
Collaborators: name: National Institute of Neurological Disorders and Stroke (NINDS)
First posted: 2017-01-23
Enrollment: 5
Sex: ALL
Minimum age (years): 18
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The goals of this study are to provide sensory information to amputees and reduce phantom limb pain via electrical stimulation of the lumbar spinal cord and spinal nerves. The spinal nerves convey sensory information from peripheral nerves to higher order centers in the brain. These structures still remain intact after amputation and electrical stimulation of the dorsal spinal nerves in individuals with intact limbs and amputees has been demonstrated to generate paresthetic sensory percepts referred to portions of the distal limb. Further, there is recent evidence that careful modulation of stimulation parameters can convert paresthetic sensations to more naturalistic ones when stimulating peripheral nerves in amputees. However, it is currently unclear whether it is possible to achieve this same conversion when stimulating the spinal nerves, and if those naturalistic sensations can have positive effects on phantom limb pain. As a first step towards those goals, in this study, the investigators will quantify the sensations generated by electrical stimulation of the spinal nerves, study the relationship between stimulation parameters and the quality of those sensations, measure changes in control of a prosthesis with sensory stimulation, and quantify the effects of that stimulation on the perception of the phantom limb and any associated pain.

Detailed description: During the study, FDA-cleared spinal cord stimulator leads will be placed in the lumbar epidural space of lower limb amputees and steered laterally towards the dorsal spinal roots under fluoroscopic guidance. This approach is essentially identical to the FDA-cleared procedure in which these devices are placed in the lumbar epidural space for treatment of intractable low back and leg pain. In that procedure, it is common clinical practice to place 2-3 leads temporarily in the epidural space through a percutaneous approach and perform a multiday trial to determine if the patient experiences any pain reduction from spinal cord stimulation. Following the trial, the percutaneous leads are typically removed by gently pulling on them, and the patient is referred to a neurosurgeon for permanent surgical implantation.

Similarly, in this study, the device will be tunneled percutaneously through the skin and secured in place with tape or suture. Using the stylet included with the spinal cord stimulator leads, the devices will be steered laterally under fluoroscopic guidance to target the dorsal spinal nerves. During lab experiments, the leads will be connected to an external stimulator. In this study, the devices will remain in the epidural space for less than 30 days and will be removed by gently pulling on the external portion. Throughout the study, the investigators will perform a series of psychophysical evaluations to characterize the sensory percepts evoked by epidural stimulation, along with functional evaluations of the effects of stimulation on the ability to control a prosthetic limb. In addition, the investigators will perform surveys to characterize changes in phantom limb sensation and pain that occur during stimulation.

Eligibility criteria: Inclusion Criteria:

* have an amputation of at least one lower limb, at a level between the ankle and hip joints
* be at least 6 months post-amputation at time of lead placement

Exclusion Criteria:

* women who are pregnant or breast-feeding
* has any serious diseases or disorders that affect ability to participate
* currently receiving medications that may affect blood coagulation
* allergic to contrast medium, or has kidney failure that could be exacerbated by contrast agent
* implanted metallic devices that are not cleared for MRI

Primary outcomes:
measure: Stimulation perceptual thresholds to a variety of stimulus parameters
timeFrame: 30 days
measure: Stimulation neurophysiology thresholds to a variety of stimulus parameters
timeFrame: 30 days
Secondary outcomes:
measure: Location of evoked sensory percepts
timeFrame: 30 days
measure: Qualitative self-report of evoked sensations
timeFrame: 30 days
measure: Change (reduction) in pain ratings
timeFrame: 30 days
measure: Ability to use a prosthetic limb with neural signals
timeFrame: 30 days
Other outcomes:
Locations:
city: Pittsburgh
country: United States
facility: Debbie
state: Pennsylvania
Study officials:
affiliation: University of Pittsburgh
name: Lee Fisher, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Ziegler-Graham K, MacKenzie EJ, Ephraim PL, Travison TG, Brookmeyer R. Estimating the prevalence of limb loss in the United States: 2005 to 2050. Arch Phys Med Rehabil. 2008 Mar;89(3):422-9. doi: 10.1016/j.apmr.2007.11.005.
citation: Etter K, Borgia M, Resnik L. Prescription and repair rates of prosthetic limbs in the VA healthcare system: implications for national prosthetic parity. Disabil Rehabil Assist Technol. 2015 Nov;10(6):493-500. doi: 10.3109/17483107.2014.921246. Epub 2014 May 22.
citation: Raichle KA, Hanley MA, Molton I, Kadel NJ, Campbell K, Phelps E, Ehde D, Smith DG. Prosthesis use in persons with lower- and upper-limb amputation. J Rehabil Res Dev. 2008;45(7):961-72. doi: 10.1682/jrrd.2007.09.0151.
citation: Deer TR, Grigsby E, Weiner RL, Wilcosky B, Kramer JM. A prospective study of dorsal root ganglion stimulation for the relief of chronic pain. Neuromodulation. 2013 Jan-Feb;16(1):67-71; discussion 71-2. doi: 10.1111/ner.12013. Epub 2012 Dec 14.
citation: Liem L, Russo M, Huygen FJ, Van Buyten JP, Smet I, Verrills P, Cousins M, Brooker C, Levy R, Deer T, Kramer J. A multicenter, prospective trial to assess the safety and performance of the spinal modulation dorsal root ganglion neurostimulator system in the treatment of chronic pain. Neuromodulation. 2013 Sep-Oct;16(5):471-82; discussion 482. doi: 10.1111/ner.12072. Epub 2013 May 13.