Projected cost to continue was not supported by the study budget and additional funds could not be obtained so the decision to close the study was made.

This study is being done to assess the safety of using the Angel Concentrated Platelet Rich Plasma System to process Platelet Rich Plasma (PRP) to treat arthritis of the low back (lumbar spondylosis).

This study is a pilot of the safety of using the FDA cleared Angel® Concentrated Platelet Rich Plasma System and Angel® cPRP Processing Set to process PRP to treat arthritis of the low back (lumbar spondylosis). Subjects will be screened at outpatient clinic visit appointments and interested qualified subjects will be consented and offered participation in this trial. Once consent has been obtained baseline values will be established and subjects will begin treatment and follow-up for the next 12 months. A final visit for evaluation and collection of lab samples will be conducted at the end of the study.

Inclusion Criteria:

• Clinical and radiographic (MRI, CT or lumbar x-ray) evidence of symptomatic facet arthropathy involving the bilateral bottom two facets (e.g., L4-5 or L5-6 and L5-S1 or L6-S1).
• Positive response, defined according to current clinical standards for the diagnosis of facet-mediated low back pain as greater than or equal to 75% pain improvement (as reported by patient) to diagnostic medial branch nerve blocks, one block with lidocaine and the other with bupivacaine.
• Low back pain VAS score of greater than or equal to 5 at the clinical visit just prior to the first medial branch nerve block.

Exclusion Criteria:

• Prior facet related procedure (intraarticular corticosteroid injection, radiofrequency ablation (RFA)) in last 6 months or prior fusion in the bottom two facets.
• Current opioid use of greater than 50mg oral morphine milligram equivalents per day.
• No advanced imaging (MRI, CT or lumbar x-ray) of the lumbar spine within the last 6 months.
• BMI > 34.99 (WHO class I obesity).
• Active systemic or local infection as evidenced by fever >100.4 degrees Fahrenheit, or any other clinical signs or symptoms of infection within 24 hours of the procedure.
• On anticoagulation drug and has been on hold for less than 7 days prior to the investigational procedure.
• Imaging evidence of high likelihood of failure for intra-articular injection in the opinion of the PI or delegate review of MRI, CT or lumbar x-ray imaging.
• History of chronic thrombocytopenia (or pre-operative platelet count less than 195,000 per μl).
• Undergoing chemotherapy at time of injection.
• Pregnant or breastfeeding.
• Use of illicit drugs within 30 days prior to study entry.
• NSAID use during the pre-procedural period (one week before Treatment Day 0).
• Preoperative hematocrit less than 36%.
• History of hemodynamic instability or inability to maintain stable oncotic pressure.
• History of prolonged clotting times.
• Prior history of lumbar procedure.
• Redness, swelling, rash or other concerning lesions at the injection site just prior to the procedure.
• Prior history of allergy to lidocaine or other local anesthetic agent.