Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report

Ultrasound guide technology, which can provide real-time visualization of the needle tip and tissues and avoid many adverse events, is widely used in minimally invasive therapy. However, the studies on ultrasound-guided Lateral recess block (LRB) are limited, this is probably because there is no recognized standard method for ultrasound scanning. This study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis (LRS). A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower limb. Physical examination showed tenderness on the spinous process and paraspinal muscles from L1 to S1, extensor hallucis longus and tibialis anterior weakness (muscle strength: 4-), and a positive straight leg raising test in the left lower limb (60°). Magnetic resonance imaging showed L4-L5 disc degeneration with left LRS and nerve root entrapment. Subsequently, the patient was diagnosed with LRS. This patient was treated with a novel ultrasound-guided LRB approach. The patient's symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month follow-up. This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane technique. Further studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS.