Epidural steroid injections and selective nerve root blocks.

Epidural steroid injections and lumbar nerve root block/steroid injection are commonly performed interventional treatments for spine-related pain. These procedures are the foundation of any image-guided spine pain management practice. While more generic and not target-specific, epidural steroid injections are highly effective in a large proportion of patients, including patients with axial pain (neck or low back pain), radiculopathy, or spinal stenosis with neurogenic claudication. When isolated lumbar nerve root irritation is more clearly suspected, transforaminal nerve root blocks can provide useful diagnostic information as well as deliver more specifically targeted steroid treatment. Sustained pain relief can be achieved in a substantial number of patients with both types of procedure. Here we review the clinical indications and technical approach to these fundamental image-guided procedures. Fluoroscopy can be the routine approach to all injections. Computed tomography or computed tomographic fluoroscopy can be used as the primary approach in lumbar epidural or nerve root injections or be used as an alternative technique in unique cases. While the basic technical approach to epidural steroid administration in the cervical, thoracic, and lumbar regions is similar, each region has unique issues that must be addressed.

Vertebroplasty and vertebral augmentation techniques.

Vertebroplasty, the percutaneous administration of acrylic bone cement into a vertebral body, was developed in France in 1984, initially as a treatment for a painful vertebral hemangioma. Subsequent adaptations of the technique, development of materials and devices, and expansion of indications have led to many vertebral augmentation variants that have proven highly successful in treating pain related to osteoporotic compression fractures and vertebral body pathology, such as metastasis and myeloma. Vertebroplasty involves the image-guided percutaneous placement of a bone access needle into the affected vertebral body, followed by injection of the bone cement under intermittent imaging to assure appropriate placement of the cement. Supplemental techniques, such as the use of a balloon to create a cavity in the vertebral body, and attempt restoration of height have also been developed. The indications for the procedure, potential risks, and basics of the technique are reviewed here. With careful attention to technique, vertebral augmentation is a very safe and highly effective treatment for back pain related to vertebral body compression and bony pathology.

Modic changes on MR images as studied with provocative diskography: clinical relevance--a retrospective study of 2457 disks.

PURPOSE: To assess the value of vertebral body endplate signal intensity (Modic) changes on magnetic resonance (MR) images in predicting a painful disk, with provocative diskography as the reference standard. MATERIALS AND METHODS: Lumbar spine diskograms and prediskogram MR images of 736 patients (2457 disks) were retrospectively reviewed as part of an institutional review board-approved HIPAA-compliant protocol. Each disk was assigned a Modic subtype: type 0, normal; type 1, nonfatty high signal intensity; type 2, fatty; and type 3, sclerosis. Statistical analysis involved use of a 2 x 2 contingency table of diskogram results for each of the subtypes. The subtype sensitivity, specificity, positive predictive value (PPV), negative predictive value, and confidence intervals (CIs) were calculated. Similar analyses of other MR variables (such as disk herniation, high signal intensity zone, and spondylolisthesis) and type 1 signal intensity changes also were performed. RESULTS: Type 1 changes (n = 155) had a high PPV (0.81; 95% CI: 0.74, 0.87) for a provocative diskogram. Type 2 changes (n = 126) had a lower PPV (0.64; 95% CI: 0.55, 0.72) for a positive diskogram. Type 3 changes (n = 21) had a PPV (0.57; 95% CI: 0.34, 0.78) that was not significant for a positive diskogram. The PPV of an endplate with a type 1 change (hereafter, type 1 endplate) for a tear in the annulus fibrosis of the disk was also insignificant (0.14; 95% CI: 0.09, 0.20). A similar analysis between a type 1 endplate and the presence of a disk herniation (PPV, 0.26; 95% CI: 0.19, 0.34) and between a type 1 endplate and vertebral body spondylolisthesis (PPV, 0.28; 95% CI: 0.20, 0.35) were significant. CONCLUSION: Type 1 signal intensity changes on MR images have a high positive predictive value in the identification of a pain generator.