A new paradiscal injection technique for the relief of back spasm after chemonucleolysis

Back spasm, or spasm of the back muscles, is the commonest adverse reaction encountered after chemonucleolysis. In order to overcome this troublesome complication, the authors present a new 'paradiscal injection technique'. After the injection of chymopapain into the affected disc, the needle is withdrawn to just outside the annulus. Bupivacaine is injected into the paradiscal 'space' which acts upon the paravertebral muscles. Eighty consecutive patients have been treated by chemonucleolysis with paradiscal injection for pain relief. All patients were discharged the same day or the following day and no immediate complications occurred. When reviewed 3 weeks later, only three (3.8%) patients complained of back pain (which was different in character to that present before the injection or was exacerbated by the injection). Pain persisted in the same patients until 6 months after the injection but was negligible. None of the remaining patients had developed back pain as a result of chymopapain. The authors suggest that the addition of paradiscal injection of bupivicaine after cymopapain injection can reduce the incidence of spasm of the back muscles. This technique is a major contribution to increasing the efficacy of chemonucleolysis for the treatment of herniated lumbar disc.