PNS vs RFA for Facet Joint Pain

• Sprint PNS system (Device): Temporary electrical stimulation of the medial nerve with implanted wires and wearable stimulator
• Radiofrequency Ablation (Procedure): Thermal ablation of the medial nerve

Primary outcomes

• Multifidus muscle activity [pre-treatment]: Muscle contraction quantification via shear wave elastography
• Multifidus muscle activity [within two weeks of treatment completion]: Muscle contraction quantification via shear wave elastography
• Multifidus muscle activity [12 months after pre-treatment measurement]: Muscle contraction quantification via shear wave elastography

Secondary outcomes

• Pain Intensity [pre-treatment]: Visual Analog Scale, scale range 1 - 10, 10 being worse possible pain.
• Pain Intensity [within two weeks of treatment completion]: Visual Analog Scale, scale range 1 - 10, 10 being worse possible pain.
• Pain Intensity [12 months after pre-treatment measurement]: Visual Analog Scale, scale range 1 - 10, 10 being worse possible pain.
• Oswestry Disability Index [pre-treatment]: Survey evaluating disability level, 0 - 4 No disability 5 - 14 Mild disability 15 - 24 Moderate disability 25 - 34 Severe disability 35 - 50 Completely disabled
• Oswestry Disability Index [within two weeks of treatment completion]: Survey evaluating disability level, 0 - 4 No disability 5 - 14 Mild disability 15 - 24 Moderate disability 25 - 34 Severe disability 35 - 50 Completely disabled
• Oswestry Disability Index [12 months after pre-treatment measurement]: Survey evaluating disability level, 0 - 4 No disability 5 - 14 Mild disability 15 - 24 Moderate disability 25 - 34 Severe disability 35 - 50 Completely disabled
• PROMIS-29 v2.0 [pre-treatment]: Survey assessing pain intensity using a single 0-10 numeric rating item and seven health domains (physical function, fatigue, pain interference, depressive symptoms, anxiety, ability to participate in social roles and activities, and sleep disturbance)
• PROMIS-29 v2.0 [within two weeks of treatment completion]: Survey assessing pain intensity using a single 0-10 numeric rating item and seven health domains (physical function, fatigue, pain interference, depressive symptoms, anxiety, ability to participate in social roles and activities, and sleep disturbance)
• PROMIS-29 v2.0 [12 months after pre-treatment measurement]: Survey assessing pain intensity using a single 0-10 numeric rating item and seven health domains (physical function, fatigue, pain interference, depressive symptoms, anxiety, ability to participate in social roles and activities, and sleep disturbance)
• isometric back strength [pre-treatment]: Measurement of peak force generated by the torso in extension in Newtons
• Isometric back strength [within two weeks of treatment completion]: Measurement of peak force generated by the torso in extension in Newtons
• isometric back strength [12 months after pre-treatment measurement]: Measurement of peak force generated by the torso in extension in Newtons
• Functional Reach [pre-treatment]: distance between the length of an outstretched arm in a maximal forward reach, 10"/25 cm or greater Low risk of falls, 6"/15cm to 10"/25cm Risk of falling is 2x greater than normal, 6"/15cm or less Risk of falling is 4x greater than normal, Unwilling to reach Risk of falling is 8x greater than normal.
• Functional Reach [within two weeks of treatment completion]: distance between the length of an outstretched arm in a maximal forward reach, 10"/25 cm or greater Low risk of falls, 6"/15cm to 10"/25cm Risk of falling is 2x greater than normal, 6"/15cm or less Risk of falling is 4x greater than normal, Unwilling to reach Risk of falling is 8x greater than normal.
• Functional Reach [12 months after pre-treatment measurement]: distance between the length of an outstretched arm in a maximal forward reach, 10"/25 cm or greater Low risk of falls, 6"/15cm to 10"/25cm Risk of falling is 2x greater than normal, 6"/15cm or less Risk of falling is 4x greater than normal, Unwilling to reach Risk of falling is 8x greater than normal.
• Repetitive Trunk Rotation [pre-treatment]: Time to complete 20 rotations, seconds, longer times are worse performance.
• Repetitive Trunk Rotation [within two weeks of treatment completion]: Time to complete 20 rotations, seconds, longer times are worse performance.
• Repetitive Trunk Rotation [12 months after pre-treatment measurement]: Time to complete 20 rotations, seconds, longer times are worse performance.
• Repeated Chair Stands [pre-treatment]: Time to perform 5 repeated chair stands, higher times mean worse outcomes.
• Repeated Chair Stands [within two weeks of treatment completion]: Time to perform 5 repeated chair stands, higher times mean worse outcomes.
• Repeated Chair Stands [12 months after pre-treatment measurement]: Time to perform 5 repeated chair stands, higher times mean worse outcomes.
• Pfirmmann grade [pre-treatment]: Degeneration of lumbar discs at the treated level, grade 1 - 5, 1 is normal and 5 is completely collapsed disc.
• Pfirmmann grade [within two weeks of treatment completion]: Degeneration of lumbar discs at the treated level, grade 1 - 5, 1 is normal and 5 is completely collapsed disc.
• Pfirmmann grade [12 months after pre-treatment measurement]: Degeneration of lumbar discs at the treated level, grade 1 - 5, 1 is normal and 5 is completely collapsed disc.
• t2-relaxation time [pre-treatment]: T2 relaxation time of the disc at the treated level. Lower values indicate more degeneration.
• t2-relaxation time [within two weeks of treatment completion]: T2 relaxation time of the disc at the treated level. Lower values indicate more degeneration.
• t2-relaxation time [12 months after pre-treatment measurement]: T2 relaxation time of the disc at the treated level. Lower values indicate more degeneration.
• 2-point dixon MRI [pre-treatment]: Intramuscular fat percentage, higher percentage means worse outcome.
• 2-point dixon MRI [within two weeks of treatment completion]: Intramuscular fat percentage, higher percentage means worse outcome.
• 2-point dixon MRI [12 months after pre-treatment measurement]: Intramuscular fat percentage, higher percentage means worse outcome.

Sex: All, ages: 18 Years to 80 Years

Inclusion Criteria:

1. Age range (18-80 years): The age range of the patient population at Hershey Medical Center with facet pain is 24 to 90 years old, with a mean age of 63 years old. Due to the physical tests planned in the study, the maximum age limit will be restricted to 80 years old.
2. English Speaking: Adults who only speak other languages will not be included because of the lack of feasibility of employing reliable instruments and interviewers fluent in other languages.
3. Facet Joint Pain: male and female patients having a diagnosis of facet joint pain based upon accepted diagnostic criteria (i.e., two positive nerve blocks) and assessed by an experienced physical therapist or physician.
4. Indication for Surgical Procedure: Physical therapy is the first line of action for facet joint pain. If PT is not effective, patients are eligible for RFA or PNS.

Exclusion Criteria:

1. Previous Spinal Conditions Surgery: We will exclude patients with other spinal conditions like scoliosis or who have received previous spinal surgeries.
2. Systemic neurological or neuromuscular disease: Such disorders (e.g., stroke, muscular dystrophy, myopathies) affect muscle and may confound muscle data and/or balance and physical performance data.
3. Allergic reaction to ultrasound gels: It is possible, although rare, that patients develop allergic reaction to ultrasound gels. Those subjects will be excluded from the study.
4. Physical Activity: Subjects will be asked to fill out the Physical Activity Readiness Questionnaire (PAR-Q), and if they answer yes to any of the questions, they need to be cleared by their physician prior to participating in the study.
5. Current infection, illness, or condition: Individuals with a current infection, illness, or condition (e.g., uncontrolled blood pressure, pregnancy) that may affect their ability to safely participate will be excluded.
6. Mental incompetency: Individuals who cannot legally consent themselves to the surgical procedure and participation in the research study, will not be considered for inclusion.
7. Patients who have a Deep Brain Stimulation (DBS) system.
8. Patients who have an implanted active cardiac implant (e.g. pacemaker or defibrillator).
9. Patients who have any other implantable neuro-stimulator whose stimulus current pathway may overlap with that of the SPRINT System.

• Daniel H. Cortes, Ph.D., Principal investigator, Penn State University