Obturator Nerve Block Using Ultrasound-guided Intraneural Alcohol Injection in Patient with Hip Adductor Spasticity

ABSTRACT

OBJECTIVE: To investigate the effects of obturator nerve blocks with ultrasound guided intraneural alcohol injection. METHOD: Nine quadriplegic patients suffering hip adductor spasticity were included in this study. The obturator nerve was identified at just below inguinal ligament area on anteromedial surface of upper leg at supine position. An 23 G needle was inserted into anterior branch of obturator nerve under real time ultrasonography. The 50% alcohol solution was injected 3~5 ml at a time within the epineurium of the anterior branch of obturator nerve until the expanding nerve was visualized. We examed modified Ashworth scale (MAS) of hip adductor and passive range of movement of hip abduction at supine position at study entry, 1, 4, and 12 weeks after ultrasound guided intraneural injection. RESULTS: There were statistically significant improvement was seen in MAS of hip adductors and hip abduction angle at 1, 4, and 12 weeks after ultrasound guided intraneural injection, compared with parameters measured at previous injection (p<0.05). CONCLUSION: Ultrasound guided intraneural alcohol injection into anterior branch of obturator nerve for treatment of hip adductor spasticity in patients with quadriplegia is an effective and safe procedure for relieving localized spasticity of the hip adductors.