Evaluation of interadductor approach in neurolytic blockade of obturator nerve in spastic patients.

Background: Spasticity is a syndrome associated with a persistent increase in involuntary reflex activity of a muscle in response to stretch. Adductor muscle spasticity is a common complication of spinal cord and brain injury. It needs to be treated if it interferes with activities of daily living and self-care. Obturator neurolytic blockade is one of the cost-effective therapeutic possibilities to treat spasticity of adductor group of muscles. In this study, we assessed the efficacy of interadductor approach in alleviating the spasticity.

Methods: Obturator neurolysis using 8-10 ml 6% phenol was given with the guidance of a peripheral nerve stimulator in 20 spastic patients. Technical evaluation included number of attempted needle insertions, time to accurate location of the nerve, depth of needle insertion, and success rate. Pain, spasticity, hip abduction range of motion (ROM), number of spasms, gait, and hygiene were evaluated at 1(st) hour, 24(th) hour, end of the 1(st) week, and in the 1(st), 2(nd), and 3(rd) months following the intervention.

Results: The success rate was 100% with mean time to accurate nerve location 4.9±2.06 min. Average depth of needle insertion was 2.91±0.32 cm. Compared with the scores measured immediately before the block, all studied parameters improved significantly. An increase in the Modified Ashworth Scale values was observed in the 2(nd) and 3(rd) months, but they did not reach their initial values.

Conclusion: The interadductor approach proved to be accurate and fast, with a high success rate. Phenol blockade is an efficient and cost-effective technique in patients with adductor spasticity. It led to a decrease in spasticity and pain with an increase in the ROM of the hip and better hygiene, with an efficacy lasting for about 3 months.