Earticle

Percutaneous epidural neuroplasty (PEN) is an interventional treatment option for chronic low back and lower extremity radicular pain that is refractory to conservative management or conventional epidural steroid injection. Traditional caudal PEN using a Racz catheter has been widely used; however, catheter manipulation can be difficult when the target lesion is located above L5/S1 or when severe spinal stenosis, postoperative adhesion, or degenerative anatomical changes are present. The retrodiscal approach allows more direct access to the disc–nerve interface and may provide targeted treatment around the affected nerve root while avoiding the vascular risk associated with the conventional safe triangle approach. The Whip catheter® is a steerable catheter system designed for retrodiscal approach PEN. Its unidirectional steerable tip, stylet-assisted stiffness, and blunt-tip side-hole needle may facilitate selective catheter placement, local drug delivery, and hydrostatic or chemical adhesiolysis near the target lesion. However, because the retrodiscal approach is performed close to the intervertebral disc and nerve root, careful fluoroscopic guidance, contrast confirmation, and monitoring for intradiscal or intravascular injection are essential. This review summarizes the anatomical rationale, technical considerations, potential advantages, limitations, and safety issues of retrodiscal approach PEN using the Whip catheter.

Complex regional pain syndrome (CRPS) is a clinical diagnosis and may be difficult to differentiate from other conditions, particularly in the early stage. We report the case of a 17-year-old male who presented with right ankle pain two months after a ligament injury. At presentation, he exhibited hyperalgesia, allodynia, asymmetry in skin temperature and color, edema, and increased uptake on three-phase bone scintigraphy, findings raising concern for early-stage CRPS. A lumbar sympathetic ganglion block was performed, and transient improvement in pain and swelling was observed. However, four days after the procedure, the patient developed progressive erythema, swelling, and bullae formation in the affected ankle. Although laboratory evaluation revealed only mild leukocytosis without other significant abnormalities, a soft tissue infection was suspected. Empirical antibiotic therapy was initiated, resulting in marked improvement in both pain and swelling. This case highlights that early CRPS and soft tissue infection such as cellulitis may present with overlapping clinical features, leading to diagnostic confusion, and may also coexist. It underscores the importance of ongoing reassessment and careful differential diagnosis when new inflammatory signs emerge during follow-up.

The transversus abdominis plane (TAP) block is utilized for managing somatic pain in the anterolateral abdominal wall. In cases of intractable cancer pain, neurolytic TAP block using alcohol can provide long-term relief. However, reports on TAP neurolysis remain limited, and the concentration and dosage of alcohol vary widely. High concentrations (80–100%) are commonly used for neurolysis, but they carry risks of neurotoxicity and injection-related pain. In an effort to reduce these adverse effects, we explored the use of a moderate alcohol concentration for pain management. TAP neurolysis was performed by sequential injection of 0.75% ropivacaine followed by a mixture of ropivacaine and 100% alcohol within the TAP space, resulting in a final total volume of approximately 15 mL with an estimated alcohol concentration of 50%. The patient experienced immediate and sustained relief from right flank pain without procedural complications. This case suggests that a moderate concentration of alcohol may effectively manage cancer-related abdominal wall pain while minimizing the associated risks. Further prospective studies are needed to establish optimal concentrations and dosages for TAP neurolysis.

Spinal pain is frequently encountered in pain clinics and is often attributed to benign musculoskeletal conditions; however, serious underlying diseases may present with similar symptoms, leading to diagnostic challenges. We report two cases that illustrate clinical pitfalls in interpreting spinal magnetic resonance imaging (MRI) in patients with cervicothoracic pain. The first case involved a 60-year-old man presented with persistent posterior neck and upper back pain accompanied by weight loss and sleep disturbance. On the outside cervical spine MRI, the lesion was overlooked because it was located beyond the primary region of interest on the far lateral sagittal images; subsequent chest computed tomography (CT) revealed a Pancoast tumor. In the second case, a 64-year-old man was referred for a bone biopsy after multifocal signal alterations on spinal MRI were interpreted as suspicious for malignancy at a primary clinic. However, the biopsy revealed only reactive marrow changes, and his symptoms improved after a cervical epidural block. These cases demonstrate that while MRI is indispensable in the evaluation of spinal pain, it should not be considered definitive without careful clinical correlation. Thorough history-taking, vigilance regarding red flags, and careful review of all imaging planes and adjacent anatomical structures are essential to avoid delayed diagnosis or unnecessary invasive intervention in pain clinic practice.

Thoracic transforaminal epidural steroid injection (TFESI) is a procedure often performed for managing thoracic radicular pain. Postdural puncture headache (PDPH) and pneumocephalus are complications occasionally reported in epidural injection with interlaminar approach. We report a rare case of both complications following thoracic TFESI. A 38-year-old woman underwent right T12 TFESI for chronic right upper abdominal and subcostal pain. Two hours after the procedure, she developed severe postural headache accompanied by nausea and vomiting. Brain computed tomography demonstrated intradural free air in the right prepontine/suprasellar cistern, and third ventricle. Although the intracranial air volume was small, the positional nature of the headache and the prompt response to epidural blood patch suggested that PDPH was the main contributor, while pneumocephalus may also have contributed to the symptoms. Since contrast spread was confirmed only before medication injection, delayed dural puncture may have occurred during subsequent syringe exchange or drug administration. A small amount of air may have entered the subarachnoid space during syringe replacement through the three-way stopcock system. The presence of an underlying meningeal cyst, such as a Tarlov cyst, could not be excluded because spinal MRI was unavailable. The patient was treated with epidural blood patch (EBP) at T12/L1 level, resulting in complete symptom resolution. Fluoroscopic images should be carefully examined to reduce dural puncture, furthermore, air should be completely removed from devices during TFESI.