Treatment of discogenic low back pain by minimally invasive lumbar disc shunt

Abstract

Objective To study the mechanism of minimaliy invasive lumbar disc shunt on treating discogenic low back pain, and analyze its short-term clinical outcome. Methods First, use nylon suture to perform a shunt study about its ability to change acid fluid＇ s PH. Second, evaluate the influence of proteoglycan＇ s content pre-and post-nylon suture implanting into lumber disc of sheep, meanwhile, observe nylon suture＇ s biocompatibility inside of lumbar disc. Third, a clinical trial is per-formed , which is named ＂disc shunt＂. Fifteen patients were diagnosed as discogenic low back pain by discography. All of them accepted ＂disc shunt＂ through pathway of discography at once, local anesthesia was used in all cases. Patients had shunts （using nylon suture） implanted into the following level of discs： one at L3-4, six at L4-5, seven at L5S1, and one at both L3-4 and L4-5. Clinical outcome evaluation is based on VAS score, ODI score and radiology at one week, three months, one year and two year after implantation. Results In virto study showed pH of lactic acid solution was gradually raised from 4.0 to 7.14 after shunt by nylon suture. Shunted discs of sheep were harvested at one, three, twelve and twenty-four months. Safranine 0 staining showed gradually increasing of proteoglycans in disc. No obvious inflammatory reaction surround nylon suture after 24 months observation. Nylon suture＇ s bioeompatibility was satisfactory inside lumbar disc. For clinical trial study, the low back pain and disability was significantly improved after operation. At the final twenty-four months follow up, evaluations showed all of the patients＇ VAS and ODI scores were reduced significantly, average rate of VAS scores improvement was 79.16%± 12.33%, and average rate of ODI was 77.42%±12.20%. Radiological examinations after implant showed no reduction of disc height index, and no aggressive disc degeneration according to Thompson scale. In addition, shunted discs were whitened under MRI, probably from disc hydration through the disc shunts. Conclusion Percutaneous disc shunt is an efficacious therapy for discogenic low back pain with multi- ple advantages such as being minimally invasive, having few risks, reducing pain and disability, and having treatment concurrent with diagnostic discography. Key words: Intervertebral disc degeneration; Low Back Pain; Intervertebral disc; Surgical procedures, minimally invasive