The Effectiveness of Ultrasound Guidance in Caudal Epidural Block

STUDY DESIGN: A prospective study. OBJECTIVES: To evaluate the effectiveness of ultrasound guidance in caudal epidural block and sonographic feature of sacral hiatus. SUMMARY OF LITERATURE REVIEW: High success rate of ultrasound-guided regional nerve block has been reported and recently, ultrasound-guided nerve block in spinal field has been introduced. MATERIALS AND METHODS: Ultrasound-guided caudal epidural block was performed in 48 patients with radiating pain to leg. Patient was placed in the prone position and sonographic image of sacral hiatus was obtained using linear probe. After measuring the intercornual distance, thickness of sacrococcygeal membrane and depth of sacral canal in transverse view, then the probe was rotated 90degrees to obtain the longitudinal view of the sacral hiatus. Under ultrasound guidance, a 21-gauge needle was inserted into the sacral hiatus in parallel with sacrum base. After contrast dye injection, needle placement was checked by the fluoroscopy and then medication was injected into the caudal epidural space. We investigated the change of radiating pain after caudal epidural block using visual analogue scale(VAS). RESULTS: The intercornual distance was mean 16.4+/-2.3mm, thickness of sacrococcygeal membrane was mean 2.8+/-0.9mm and depth of sacral hiatus was mean 2.6+/-0.9mm. There was 97.9% success rate of the caudal epidural block under ultrasound guidance. The mean VAS for radiating pain was improved from 7.5+/-0.7 before the block to 2.8+/-1.5 after the block. CONCLUSIONS: Ultrasound-guided caudal epidural block seems to provide good anatomical landmark of sacral hiatus and an effective tool with high success.

Relationship between New Osteoporotic Vertebral Fracture and Instrumented Lumbar Arthrodesis

STUDY DESIGN: Retrospective study. PURPOSE: To evaluate the relationship between a new osteoporotic vertebral fracture and instrumented lumbar arthrodesis. OVERVIEW OF LITERATURE: In contrast to the growing recognition of the importance of adjacent segment disease after lumbar arthrodesis, relatively little attention has been paid to the relationship between osteoporotic vertebral fractures and instrumented lumbar arthrodesis. METHODS: Twenty five patients with a thoracolumbar vertebral fracture following instrumented arthrodesis for degenerative lumbar disorders (study group) were investigated. The influence of instrumented lumbar arthrodesis was examined by comparing the bone mineral density (BMD) of the femoral neck in the study group with that of 28 patients (control group) who had sustained a simple osteoporotic vertebral fracture. The fracture after instrumented arthrodesis was diagnosed at a mean 47 months (range, 7 to 100 months) after the surgery. RESULTS: There was a relatively better BMD in the study group, 0.67 +/- 0.12 g/cm2 compared to the control group, 0.60 +/- 0.13 g/cm2 (p = 0.013). The level of back pain improved from a mean of 7.5 +/- 1.0 at the time of the fracture to a mean of 4.9 +/- 2.0 at 1 year after the fracture (p = 0.001). However, 12 (48%) patients complained of severe back pain 1 year after the fracture. There was negative correlation between the BMD of the femoral neck and back pain at the last follow up (r = - 0.455, p = 0.022). CONCLUSIONS: Osteoporotic vertebral fractures after instrumented arthrodesis contribute to the aggravation of back pain and the final outcome of degenerative lumbar disorders. Therefore, it is important to examine the possibility of new osteoporotic vertebral fractures for new-onset back pain after lumbar instrumented arthrodesis.