Korean Journal of Pain最新文献

Coccydynia is a debilitating pain disorder. However, its pathophysiology is not well understood. When approaching coccydynia, the exact underlying cause of pain must be identified to develop an appropriate treatment plan. The specific approach to coccydynia can vary depending on an individual's condition and the underlying cause. Thorough evaluation by a pain physician is essential to determine the most appropriate course of treatment. The purpose of this review is to examine the various causes contributing to coccygeal pain and specifically focus on the exact anatomical neurostructures, such as the anococcygeal nerve, perforating cutaneous nerve, and ganglion impar. We also reviewed the relevant clinical outcomes and suggested recommendations for each anatomical structure.

Background: Spinal N-methyl-D-aspartate (NMDA) receptor activation is attributed to remifentanil-induced hyperalgesia (RIH). However, the specific mechanism and subsequent treatment is still unknown. Previous studies have shown that the dynamin-related protein 1 (DRP1)-mitochondria-reactive oxygen species (ROS) pathway plays an important role in neuropathic pain. This study examined whether antisense oligodeoxynucleotides against DRP1 (AS-DRP1) could reverse RIH.

Methods: The authors first measured changes in paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) at 24 hours before remifentanil infusion and 4, 8, 24, and 48 hours after infusion. The expression levels of DRP1 and NR₂B were measured after behavioral testing using Western blotting. In addition, DRP1 expression was knocked down by intrathecal administration of AS-DRP1 to investigate the effects of DRP1 on RIH. The behavioral testing, the expression levels of spinal DRP1 and NR₂B, and dorsal mitochondrial superoxide were measured. Changes in mitochondrial morphology were assessed using electron microscopy.

Results: After remifentanil exposure, upregulation of spinal DRP1 and NR₂B was observed along with a reduction in PWMT and PWTL. In addition, AS-DRP1 improved RIH-induced PWTL and PWMT (P < 0.001 and P < 0.001) and reduced remifentanil-mediated enhancement of spinal DRP1 and NR₂B expression (P = 0.020 and P = 0.022). More importantly, AS-DRP1 reversed RIH-induced mitochondrial fission (P = 0.020) and mitochondrial superoxide upregulation (P = 0.031).

Conclusions: These results indicate that AS-DRP1 could modulate NMDA receptor expression to prevent RIH through the DRP1-mitochondria-ROS pathway.

Background: This study is primarily aimed to determine whether transcutaneous electrical nerve stimulation (TENS) and interferential current (IFC) treatments have any effect on central sensitization (CS) in patients with knee osteoarthritis (OA) and to investigate which treatment is more effective.

Methods: In this randomized controlled trial, 80 patients were randomized into four treatment groups: TENS, Plasebo-TENS, IFC, and Plasebo-IFC. All interventions were applied 5 times a week for 2 weeks. Primary outcome was pressure pain threshold (PPT), which is accepted as the objective indicator of CS, at the painful knee and at the shoulder as a painless distant point. Other outcome measures were the visual analog scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index, Timed Up and Go Test, pain catastrophizing scale, Beck Depression Inventory, and Tampa Scale of Kinesiophobia.

Results: All assessment parameters were improved, without a significant difference among the groups except PPT. PPT scores were significantly improved in TENS and IFC groups when compared with the sham groups at 2 weeks and 3 months. In addition, this improvement was even more pronounced in the TENS group. Multivariable logistic regression analysis showed that the patient's inclusion in the TENS group, an initial high PPT, and an initial low VAS score were independent risk factors for improvement in the PPT.

Conclusions: This study shows that TENS and IFC reduced pain sensitivity as compared to placebo groups in patients with knee OA. This effect was more pronounced in the TENS group.

Background: Recent attention has been directed towards fatty infiltration in the cervical extensor muscles for predicting clinical outcomes in several cervical disorders. This study aimed to investigate the potential association between fatty infiltration in the cervical multifidus and treatment response following cervical interlaminar epidural steroid injection (CIESI) in patients with cervical radicular pain.

Methods: The data of patients with cervical radicular pain who received CIESIs between March 2021 and June 2022 were reviewed. A responder was defined as a patient with a numerical rating scale decrease of ≥ 50% from the baseline to three months after the procedure. The presence of fatty infiltration in the cervical multifidus was assessed, along with patient characteristics, and cervical spine disease severity. To assess cervical sarcopenia, fatty infiltration in the bilateral multifidus muscles was evaluated at the C5-C6 level using the Goutallier classification.

Results: Among 275 included patients, 113 (41.1%) and 162 (58.9%) were classified as non-responders and responders, respectively. The age, severity of disc degeneration, and grade of cervical multifidus fatty degeneration were significantly lower in responders. Multivariate logistic regression analysis revealed that pre-procedural symptoms (radicular pain with neck pain, odd ratio [OR] = 0.527, P = 0.024) and high-grade cervical multifidus fatty degeneration (Goutallier grade 2.5-4, OR = 0.320, P = 0.005) were significantly associated with an unsuccessful response to CIESI.

Conclusions: These results suggest high-grade cervical multifidus fatty infiltration is an independent predictor of poor response to CIESI in patients with cervical radicular pain.

Background: The data related to pain and catastrophic health expenditure (CHE) needed to be further explored. This study aims to understand the relationship between pain and CHE.

Methods: Using cross-sectional analysis of 4-year data (2015-2018) from the Korea Health Panel, the prevalence of CHE and adjusted odds ratio (AOR) by pain type were confirmed.

Results: Among participants (n = 46,597), the prevalence of pain and severe pain were 24.2% and 1.1%, respectively. The use of medical services in emergency rooms, hospitalizations, and outpatients increased in the order of pain-free, pain, and severe pain (P < 0.001). Prevalence of household CHE was 3.3% vs. 11.1% vs. 25.9%, (P < 0.001). The AOR of CHE was 1.5 (95% confidence interval [CI], 1.4-1.7) for pain and 3.1 (95% CI, 2.5-3.9) for severe pain. Household capacity to pay per year was lower and lower in the order of pain-free, pain, and severe pain ($25,094 vs. $17,965 vs. $14,056, P < 0.001). Also, the household out-of-pocket expenditure per year was higher and higher in the order of pain-free, pain, and severe pain ($1,649, $1,870, $2,331, P < 0.001).

Conclusions: It can be inferred that pain is one of the mechanisms of poverty. Positivist healthcare policies for the prevention and management of pain should be sought.

Background: Among the four genicular nerves innervating the anterior aspect of the knee, the inferior lateral genicular nerve has been omitted as a target of blocking. Some authors have suggested that the inferior lateral genicular nerve of the knee might pass beneath the lateral collateral ligament of knee. The authors aimed to study the location of the inferior lateral genicular nerve and the spread of injectate during the inferior lateral genicular nerve block.

Methods: In ten knees from fresh frozen cadavers, the authors performed on each an ultrasound-guided block of the inferior lateral genicular nerve of the knee just below the lateral collateral ligament. The needle was inserted below the lateral collateral ligament, and 2 mL of blue dye was injected. A week later, the cadavers were dissected, and the existence of the inferior lateral genicular nerve and the spread of dye around it was investigated.

Results: The proportion of inferior lateral genicular nerves branching from the common peroneal nerve was found in 8 of 10 (80.0%) cadavers. Of these eight cadavers with inferior lateral genicular nerve, five specimens (62.5%) were stained with blue dye. The common peroneal nerve was not infiltrated with dye in any specimens.

Conclusions: When 2 mL of dye was inserted inferiorly to the lateral collateral ligament, the inferior lateral genicular nerve could be blocked in 62.5% of specimens. Because the common peroneal nerve was not involved in any specimen, motor weakness would be avoided with this method.