Peripheral Nerve Stimulation(PNS) for Subacromial Impingement Syndrome(SIS)

The medical and socioeconomic impact of subacute and chronic shoulder pain is high, resulting
in 12 million visits to physicians and over $7 billion in direct costs in the United States.
The most common cause is subacromial impingement syndrome (SIS), which accounts for 30% of
all shoulder pain. Approximately 35% of patients who present with subacromial impingement
syndrome (SIS) are refractory to conservative management. For patients who have failed
conservative management, there are no established treatments to reduce the pain. The
long-term goal is to develop a therapeutic intervention to reduce pain related to subacromial
impingement syndrome(SIS). A pilot trial of 3-week percutaneous peripheral nerve stimulation
(PNS) for participants with chronic shoulder pain due to subacromial impingement syndrome
(SIS) that was refractory to conservative treatment that showed 60% of participants had
successful treatment of pain that lasted at least 3 months. Thus, the primary objective of
this 2 site randomized control trial (RCT) is to confirm the findings of this preliminary
trial and determine the efficacy of peripheral nerve stimulation (PNS) for chronic
subacromial impingement syndrome (SIS). The secondary objectives of this multisite randomized
control trial (RCT) is to explore mechanisms of peripheral nerve stimulation (PNS) for the
treatment of subacromial impingement syndrome (SIS), and to determine which characteristics
can predict successful treatment with peripheral nerve stimulation (PNS). In order to
accomplish these objectives, this trial is a multi-site, placebo controlled, double-blinded
randomized control trial (RCT) to compare the efficacy of peripheral nerve stimulation (PNS)
to sham peripheral nerve stimulation (PNS). Measures of pain, pain interference with
activities of daily living (ADLs), capacity for activities of daily living (ADLs), Quality of
life (QoL), and measures of central sensitization (pain thresholds, secondary hyperalgesia,
and temporal summation) will be measured. Participants will be followed for a total of 24
weeks after treatment has concluded.

Inclusion Criteria:

1. Shoulder pain of >3 months

2. Age>=21

3. Worst pain in the last week>=4 (0-10 scale)

4. Ability to check skin and perform dressing changes, independently or with assistance

5. Stable dose of pain medication (Not taking more than than 1 opioid or 1 non-opioid
analgesic)

Exclusion Criteria:

1. Current shoulder joint or overlying skin infection, or current bacterial infection
requiring antibiotics

2. Other chronic pain syndrome (Pain in another area of the body 15 or more days in the
last 30 (more than half of the time) or taking daily analgesics for another pain
syndrome)

3. Prior shoulder surgery to ipsilateral shoulder joint (glenohumeral, rotator cuff,
acromioclavicular (AC) Joint, etc.)

4. Corticosteroid injection in the ipsilateral shoulder in last 12 weeks

5. Uncontrolled bleeding disorder

6. Medical instability based on physician opinion after review of medical information

7. Pregnancy

8. Neurological condition affecting ipsilateral upper limb (add (such as central
neurologic injury/illness, radiculopathy, diabetic amyotrophy, Complex Regional Pain
Syndrome, etc.)

9. Current Worker's compensation claim for the ipsilateral shoulder

10. Shoulder instability, severe glenohumeral osteoarthritis(OA) based on patient symptoms
and physical examination

11. Ipsilateral shoulder injury due to severe trauma (Fall from greater than standing
height; Motor vehicle crashes; Struck by vehicle or other fast-moving projectile
(e.g., bullet, baseball, etc.); Assault (i.e., injuries intentionally inflicted by
another person))

12. Current osseus fracture in ipsilateral arm

13. Ipsilateral upper limb amputation other than a single digit (digits 2-5, partial or
full)

14. Surgical indication for shoulder treatment based on physician opinion

15. Compromised immune system (immunodeficiency or immunosuppression)

16. Current use of a Deep Brain Stimulation (DBS) system, implanted active cardiac implant
(e.g. pacemaker or defibrillator), any other implantable neuro-stimulator whose
stimulus current pathway may overlap with that of the SPRINT System

17. Patients who have a tape or adhesive allergy

18. Contraindication to Magnetic resonance imaging (metal in body, claustrophobia, body
habitus, etc) - exclude from Magnetic resonance imaging (MRI) only