Intradiscal Platelet Rich Plasma

To assess changes in pain and function in patients with discogenic low back pain after a standard of care intradiscal injection of Platelet-Rich Plasma (PRP).

Low back pain is one of a few conditions which affects all individuals through the lifespan. The etiology of low back pain is multifactorial and in many cases self-limiting, however it also is the leading cause for working age adults to be disabled with more than $87 billion spent on low back pain disorders in 2013 Lumbar disc herniation and internal disc disruption are two causes more common in these younger age groups reaching 39-42% with a predicted probability above 60% until age 50y. While the natural history of disc herniation suggests most individuals will return to a prior level of function in 3-6 months, there is a high rate of recurrent episodes which can cause short-term disability. Continued pain from a discogenic source can lead to decreased activity levels and accelerate degenerative changes in the disc and facet joints as described by Kirkaldy-Willis.

Current guidelines for treatment of axial low back pain from discogenic sources including those with radiculopathy include a 6-12-week course of conservative care including medications, therapy, acupuncture, chiropractic and exercise before an interventional paradigm of injections and/or surgical treatment. For those individuals who do not improve with conservative care and have predominately axial pain, options are limited as success rates from epidural steroid injections and surgery are 50% or less. Other treatments include chymopapain injection, intradiscal electrothermal annuloplasty (IDET), nucleoplasty, methylene blue injection, ozone injection , fibrin sealant injections. All of which have 50% or less likelihood of reducing pain more than 50%, although much of this data is from uncontrolled or prospective case-control studies only.

Platelet- rich plasma (PRP) injections stand apart from those listed above in that they are purported to be "regenerative" interventions for the diseased lumbar disc. PRP is a concentrated injectant of growth factors and anabolic factors which have in vitro and animal studies that have demonstrated upregulated proteoglycan synthesis and nucleus pulposus proliferation, restoration of disc height, healing of annular puncture wounds and anti-inflammatory effect with down regulation of TNF-alpha and IL-1. There has been limited clinical trials in humans on the effect of intradiscal PRP, including 3 trials of which 1 is a RCT and 2 are prospective series. Efficacy of intra-discal injection has shown statistically significant benefits in reduction in pain, improvement in physical function at follow-up points from 3-24 months. Each of these trials have limited sample sizes, short duration follow-up and lack of a standardized PRP preparation, making the generalizability difficult.

Eligibility Criteria:
Inclusion Criteria:

1. Age greater than 18 years of age at day of enrollment.
2. Clinical diagnosis of refractory discogenic low back pain for \>3 months.
3. Magnetic resonance imaging pathology consistent with clinical symptoms/signs or positive lumbar provocative discography according to SIS/IASP standards at one or two levels.
4. Back pain greater than leg pain with an intensity of at least 4/10 or higher using the Numerical Rating Scale (NRS).
5. Pain duration of more than 12 weeks despite trial of conservative therapy (medications, physical therapy, or chiropractic care) for 2 months.

Exclusion Criteria:

1. Refusal to participate, provide consent, or provide follow-up information for the 24-month duration of the study.
2. Contraindications to intradiscal injection of PRP (active infection, bleeding disorders, current anticoagulant or antiplatelet medication use, allergy to iodinated contrast, penicillin or clindamycin and pregnancy or breastfeeding).
3. More than 2 levels of clinical or discogram proven pain.
4. Non-discogenic source of low back pain as identified by separate diagnostic blocks.
5. Negative lumbar provocation discography.
6. Active moderate to severe lumbar radiculopathy.
7. Intradural disc herniation.
8. Spinal fracture within the past 6 months.
9. Steroid injection in the spine within the last 30 days.
10. Any intradiscal injection other than contrast dye or anesthetic in the last 30 days.
11. Prior fusion at level considered to be the source of the pain.
12. Prior lumbar spine surgery within the last 6 months.
13. AP diameter of spinal canal less than or equal to 9mm at level to be treated.
14. Severe uncontrolled medical condition.
15. Moderate to severe hepatic dysfunction.
16. Severe psychological illness.
17. History of Inflammatory arthritis.
18. Malignancy within past 5 years except basal cell or squamous cell skin cancer.
19. Current use of equal to greater than 30mg morphine-equivalent per day of opioid use.
20. A history of alcohol or drug abuse within past 5 years.
21. Use of any investigational drug within past 30 days.
22. A known allergy or sensitivity to citrate (used for processing PRP).
23. Severe anaphylactic/anaphylactoid reaction to any medications used.
24. Pending litigation involving subject's back pain.
25. No insurance coverage for any subsequent tests or procedures.
26. Disc protrusion greater than 5mm from base of vertebral body.
27. Greater than 50% disc height loss at involved level(s).
28. Inability or unwillingness to continue rehabilitation protocols.