Postoperative Peripheral Nerve Stimulation for Management of Post-amputation Pain

Not Applicable

Completed

Conditions: Neuroma
Residual Limbs
Amputation
Phantom Limb Pain
Postoperative Pain
Acute Pain
Chronic Pain

Interventions: Device: Peripheral nerve stimulation
Other: Standard Medical Therapy

Registration Number: NCT03484429

Lead Sponsor: Hunter Holmes Mcguire Veteran Affairs Medical Center

Brief Summary: Limb loss is frequently associated with postamputation pain that can be challenging to treat and often involves opioids. Advances in the field of neuromodulation has led to development of an intentionally reversible percutaneous peripheral nerve stimulation (PNS) system that has had promising results when treating chronic postamputation pain. PNS may offer sustained pain relief even after the treatment period has ended. Currently, there is no convincing evidence regarding the role of PNS in the acute postoperative period, which may be a critical time to control pain as those with higher pain appear to be at higher risk for developing persistent post-procedural pain. The investigators of this study aim to evaluate the feasibility and effects of PNS in the acute postoperative period and determine the feasibility of completing a randomized controlled treatment outcome study.

Detailed Description: 16 patients with new nontraumatic transfemoral or transtibial amputation will be enrolled in the study

Having met inclusion criteria, the patients will be randomized to experimental or control groups

Patients in the experimental group undergo placement of PNS leads within 7 days of amputation surgery

Patients in both groups will be treated with standard pharmacologic and nonpharmacologic pain therapies and evaluated weekly for 8 weeks, then at 3, 6, and 12 months postamputation

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 16

Inclusion Criteria

Nontraumatic transfemoral (above-the-knee) or transtibial (below-the-knee) amputation
Presence of postamputation pain rated at least 4 or more

Exclusion Criteria

Beck Depression Inventory score greater than 20
Systemic infection
Immunocompromised or taking immunosuppressive medications
Implanted electronic device
Pregnancy
Previous allergy to skin contact materials and/or anesthetic agent
Altered mental status
Inability to provide informed consent

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Group 1	Peripheral nerve stimulation	Standard medical therapy and 30 to 60 days of peripheral nerve stimulation starting within 7 days after surgery
Group 1	Standard Medical Therapy	Standard medical therapy and 30 to 60 days of peripheral nerve stimulation starting within 7 days after surgery
Group 2	Standard Medical Therapy	Standard medical therapy only

Primary Outcome Measures

Name	Time	Method
Average Residual Limb Pain (RLP) Score	Baseline, Weeks 1-4, Weeks 5-8, and Month 3	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate their RLP over the past 24 hours on a scale of "0"=no pain to "10"=worst pain they have ever experienced. A lower score is better. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.
Worst Phantom Limb Pain (PLP) Score	Baseline, Weeks 1-4, 5-8, and Month 3	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate their PLP over the past 24 hours on a scale of "0"=no pain to "10"=worst pain they have ever experienced. A lower score is better. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.
Worst Residual Limb Pain (RLP) Score	Baseline, Weeks 1-4, Weeks 5-8, and Month 3	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate their RLP over the past 24 hours on a scale of "0"=no pain to "10"=worst pain they have ever experienced. A lower score is better. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.
Best Residual Limb Pain (RLP) Score	Baseline, Weeks 1-4, Weeks 5-8, and Month 3	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate their RLP over the past 24 hours on a scale of "0"=no pain to "10"=worst pain they have ever experienced. A lower score is better. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.
Best Phantom Limb Pain (PLP) Score	Baseline, Weeks 1-4, Weeks 5-8, and Month 3	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate their PLP over the past 24 hours on a scale of "0"=no pain to "10"=worst pain they have ever experienced. A lower score is better. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.
Average Phantom Limb Pain (PLP) Score	Baseline, Weeks 1-4, Weeks 5-8, and Month 3.	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate their PLP over the past 24 hours on a scale of "0"=no pain to "10"=worst pain they have ever experienced. A lower score is better. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.

Secondary Outcome Measures

Name	Time	Method
Pain Catastrophizing Scale (PCS)	Baseline, Weeks 4, 8, and 12	Pain catastrophizing is the tendency to magnify the threat value of a pain stimulus and to feel helpless in the presence of pain. This is further characterized by the inability to prevent or inhibit pain-related thoughts surrounding a painful event. Pain catastrophizing affects how individuals experience pain. The PCS is a 13-item inventory of statements in which the subject is asked to rate the degree to which they agree, on a scale of "0" = not at all to "4" = all the time. The responses for each item are added for a total PCS score (range 0-52). A lower score is better.
Number Taking Opioids	Preop, Hospital Discharge, Weeks 1-4, Weeks 5-8, Week 12	The number of subjects prescribed any opioid medication and any dose. Data from Weeks 1-4 and Weeks 5-8 were averaged to obtain a numerical score for these time points.
Functional Independence Measure (FIM) Scores	Preoperative, Week 4, and Week 8	FIM mobility subscores were recorded by a physical therapist to measure the ability to walk, use a wheelchair, transfer to tub/shower, transfer to toilet, and mobility in bed, chair, and wheelchair. Scores range from "1" = subject requires total assistance for the task to "7" = complete independence. A higher score is better.
Patient Global Impression of Change (PGIC)	Weeks 4, 8, and 12	Self-report measure PGIC reflects a patient's belief about the efficacy of treatment. PGIC is a 7 point scale depicting a patient's rating of overall improvement. Patients rate their change as 1 = "very much improved," 2 = "much improved," 3 = "minimally improved," 4 = "no change," 5 = "minimally worse," 6 = "much worse," or 7 = "very much worse." A lower score is better.
Hospital Length of Stay (LOS)	Number of days from surgery to discharge	Hospital LOS was calculated from day of surgery to day of discharge from inpatient hospital ward to rehabilitation facility.
Average Oral Morphine Equivalents (OME)	Preoperative, Hospital discharge, Weeks 1-4, Weeks 5-8, and Week 12	Opioid consumption (daily OME) over time was collected for all subjects.
Pain Interference	Baseline, Weeks 4, 8, and 12	Using the Brief Pain Inventory-Short Form (BPI-SF) questionnaire, subjects were asked to rate how much pain has interfered with daily activities over the past 24 hours on a scale of "0" = no interference to "10" = completely interferes with activities. A lower score is better.
Pain Disability Index (PDI)	Weeks 4, Week 8, and Week 12	The PDI is designed to measure the degree to which aspects of life are disrupted by chronic pain. The impact of pain on various aspects of life (e.g. family/home responsibilities, recreation, social activity, occupation, sexual behavior, self-care, and life-support activities) are recorded on a 10-point scale from "0" = no disability to "10" = worst disability. The sum of scores is recorded for a total PDI score (range 0-70). A lower score is better.
30-day Readmission Rate	30 days from hospital discharge	Percent of Group that was readmitted to the hospital within 30 days following hospital discharge.