Correlation between paravertebral spread of injectate and clinical efficacy in lumbar transforaminal block

Quantitative Analysis of Real-Time Infrared Thermography for the Assessment of Lumbar Sympathetic Blocks: A Preliminary Study

Lumbar sympathetic blocks (LSBs) are commonly performed to treat pain ailments in the lower limbs. LSBs involve injecting local anesthetic around the nerves. The injection is guided by fluoroscopy which is sometimes considered to be insufficiently accurate. The main aim was to analyze the plantar foot skin temperature data acquired while performing LSBs in patients with complex regional pain syndrome (CRPS) affecting the lower limbs. Forty-four LSBs for treating lower limb CRPS in 13 patients were assessed. Pain medicine physicians visualized the infrared thermography (IRT) video in real time and classified the performance depending on the observed thermal changes within the first 4 min. Thirty-two percent of the cases did not register temperature variations after lidocaine was injected, requiring the needle to be relocated. Differences between moments are indicated using the 95% confidence intervals of the differences (CI 95%), the Cohen effect size (ES) and the significance (p value). In successful cases, after injecting lidocaine, increases at minute 7 for the mean (CI 95% (1.4, 2.1 °C), p < 0.001 and ES = 0.5), at minute 5 for maximum temperature (CI 95% (2.3, 3.3 °C), p < 0.001 and ES = 0.6) and at minute 6 for SD (CI 95% (0.2, 0.3 °C), p < 0.001 and ES = 0.5) were observed. The results of our preliminary study showed that the measurement of skin temperature in real time by infrared thermography is valuable for assessing the success of lumbar sympathetic blocks.

Ultrasound-Guided Lumbar Paravertebral Block After Pre-Designed Route on X-Ray Film for Radicular Pain Following Failed Back Surgery Syndrome: A Case Report

Background

Persistent or recurring radicular pain after lumbar surgery is a clinical condition of failed back surgery syndrome (FBSS) that seriously affects the life quality of patients. Conventional medication and physiotherapy do not fully relieve this pain. A simpler, safer, and less invasive option is lumbar selective nerve root block or paravertebral block. Here, we share our experience regarding lumbar paravertebral block for a patient with FBSS, which successfully alleviated radicular pain after lumbar surgery.

Case Presentation

An 80-year-old man with left lower limb radicular pain diagnosed as L4-5, L5-S1 intervertebral disc protrusion, spinal canal stenosis, and degenerative scoliosis underwent lumbar surgery. Four months after surgery, he experienced left lower limb radicular pain. After designing the puncture route based on X-ray film, we performed a combined ultrasound-guided L4 and L5 paravertebral block. With his improved pain control, his functional status and ability to perform daily activities also markedly improved.

Conclusion

Real-time ultrasound-guided lumbar paravertebral block performed with a pre-designed route on X-ray film can provide a simple and safe way to relieve radicular pain in FBSS.