Use of Baclofen as a Treatment for Nocturnal Calf Cramps in Individuals With Lumbar Spinal Stenosis: A Prospective Randomized Study.

OBJECTIVE: This study aimed to compare the efficacy and safety of baclofen and gabapentin in reducing leg pain from nocturnal calf cramps in lumbar spinal stenosis patients. DESIGN: In a randomized clinical trial, the patients with lumbar spinal stenosis who commonly experienced nocturnal calf cramps were included. Patients were randomly assigned to either the baclofen or gabapentin group. Overall leg pain intensity, nocturnal calf cramp frequency and severity, sleep disturbances and functional disability were assessed at baseline and after 4 and 12 wks. RESULTS: Thirty-six patients completed the 3-mo study. Both gabapentin and baclofen groups showed a significant reduction in overall leg pain, calf cramp frequency and intensity, and insomnia severity index scores from baseline to the endpoint. However, there were no significant differences between the two groups in terms of symptom reduction at different time points. The baclofen group also demonstrated a significant decrease in Oswestry Disability Index scores ( P < 0.001), while the gabapentin group did not ( P = 0.344). No adverse effects were reported in either group. CONCLUSIONS: Baclofen seems to be as effective and as safe as gabapentin in treating nocturnal calf cramps in lumbar spinal stenosis patients and even shows superiority in enhancing functional outcomes.

Subgrouping patients with zoster-associated pain according to sensory symptom profiles: A cluster analysis.

Background and goal of study: Patients with zoster-associated pain exhibit a variety of sensory symptoms and forms of pain and complain of different pain patterns. The purpose of this study is to subgroup patients with zoster-associated pain who visited a hospital using painDETECT sensory symptom scores, analyze their respective characteristics and pain-related data, and compare similarities and differences among the groups. Materials and methods: The characteristics of 1,050 patients complaining of zoster-associated pain and pain-related data were reviewed retrospectively. To identify subgroups of patients with zoster-associated pain according to sensory symptom profiles, a hierarchical cluster analysis was performed based on the responses to a painDETECT questionnaire. Demographics and pain-related data were compared among all subgroups. Results and discussion: Patients with zoster-associated pain were classified into 5 subgroups according to the distribution of sensory profiles, with each subgroup exhibiting distinct differences in the expression of sensory symptoms. Patients in cluster 1 complained of burning sensations, allodynia, and thermal sensitivity, but felt numbness less strongly. Cluster 2 and 3 patients complained of burning sensations and electric shock-like pain, respectively. Cluster 4 patients complained of most sensory symptoms at similar intensities and reported relatively strong prickling pain. Cluster 5 patients suffered from both burning and shock-like pains. Patient ages and the prevalence of cardiovascular disease were significantly lower in cluster 1. Patients in clusters 1 and 4 reported longer pain duration compared with those in clusters 2 and 3. However, no significant differences were found with respect to sex, body mass index, diabetes mellitus, mental health problems, and sleep disturbance. Pain scores, distribution of dermatomes and gabapentinoid use were also similar among the groups. Conclusions: Five different subgroups of patients with zoster-associated pain were identified on the basis of sensory symptoms. A subgroup of younger patients with longer pain duration showed specific and distinct symptoms, such as burning sensations and allodynia. Unlike patients with acute or subacute pain, patients with chronic pain were associated with diverse sensory symptom profiles.

Neuropathic pain component and its association with time elapsed since pain onset in patients with low back pain.

BACKGROUND: Time elapsed since pain onset might affect the likelihood of neuropathic component in low back pain. The aim of this study was to investigate the relationship between neuropathic pain component and pain duration in patients with low back pain and to identify factors associated with neuropathic pain component. METHODS: Patients with low back pain who received treatment at our clinic were enrolled. Neuropathic component was assessed using the painDETECT questionnaire at the initial visit. PainDETECT scores and the results for each item were compared according to pain duration category (< 3 months, 3 months to 1 year, 1 year to 3 years, 3 years to 10 years, and ≥ 10 years). A multivariate analysis was used to identify factors associated with neuropathic pain component (painDETECT score ≥ 13) in low back pain. RESULTS: A total of 1957 patients, including 255 patients who reported neuropathic-like pain symptoms (13.0%), fully satisfied the study criteria for analysis. No significant correlation between painDETECT score and pain duration was observed (ρ = -0.025, p = 0.272), and there were no significant differences between median painDETECT score or trend of change in the proportion of patients with neuropathic component and the pain duration category (p = 0.307, p = 0.427, respectively). The electric shock-like pain symptom was frequently reported in patients with acute low back pain, and the persistent pain pattern with slight fluctuations was predominant in chronic low back pain. The pattern of attacks with pain between them was much less common in patients with pain for 10 years or longer. Multivariate analysis revealed that a history of lumbar surgery, severe maximum pain, opioid use, lumbosacral radiculopathy, and sleep disturbance were significantly associated with a neuropathic component in low back pain. CONCLUSION: Time elapsed since current pain onset did not correlate with neuropathic pain component in patients with low back pain. Therefore, diagnostic and therapeutic approaches for this condition should be based on a multidimensional evaluation at assessment and not on pain duration alone.

Influence of Handgrip Strength and Psoas Muscle Index on Analgesic Efficacy of Epidural Steroid Injection in Patients With Degenerative Lumbar Spinal Disease.

BACKGROUND: Handgrip strength (HGS) and psoas muscle index (PMI) are widely used protocols for screening or diagnosing sarcopenia by measuring muscle strength and mass. Epidural steroid injection (ESI) is a common intervention for the treatment of spinal pain; however, the influence of pre-procedural sarcopenic status on therapeutic effects after ESI has not been investigated. OBJECTIVES: In the present study, whether pre-procedural HGS or PMI predicts analgesic efficacy of ESI in elderly patients with degenerative lumbar spinal disease was investigated. STUDY DESIGN: This was a retrospective observational study. SETTING: The study included patients from the outpatient department for interventional pain management at a university hospital. METHODS: Following institutional review board (IRB) approval, patients >= 65 years of age who underwent fluoroscopy-guided lumbar ESI from 2016 to 2017 in our clinic were enrolled in the present study. Good analgesia was defined as >= 50% reduction in pain score at 4 weeks after injection. Patient characteristics, pain-related factors, clinical factors, HGS, and PMI measurements were collected and analyzed using multivariate analysis to identify the predictors of good analgesia after lumbar ESI. In addition, a receiver operating characteristic curve (ROC) analysis was performed, and area under the curve (AUC) values with 95% confidence interval (CI) were calculated for the HGS. RESULTS: A total of 259 patients satisfied the study protocol requirements. HGS was significantly higher in the good analgesia group (23.12 ± 7.54 vs 16.55 ± 6.66 kg, P < 0.001). However, the PMI did not differ between the 2 groups (5.25 ± 1.55 vs 5.08 ± 1.69 cm2/m2, P = 0.406). Multivariate analysis revealed higher HGS (odds ratio, OR = 1.142, 95% CI = 1.094-1.193, P < 0.001) and low-grade foraminal stenosis (OR = 0.403, 95% CI = 0.199-0.814, P = 0.011) were significantly associated with good analgesia after injection. The AUC values with 95% CI for HGS were 0.819 (0.718-0.920) in men and 0.800 (0.732-0.869) in women. In addition, HGS cutoff values for predicting good analgesic outcomes were 26.5 kg in men and 16.5 kg in women. LIMITATIONS: This study was conducted in a single center, and sample size was relatively small. The lack of physical performance evaluation did not fully meet the current criteria for sarcopenia. In addition, post-procedural clinical data associated with disability or quality of life could not be collected. CONCLUSION: In the present study, pre-procedural HGS was an independent predictor of analgesic efficacy after ESI in elderly patients with degenerative lumbar spinal disease. However, the PMI was not associated with pain relief after injection.

Neuropathic-like Pain Symptoms and Their Association with Muscle Strength in Patients with Chronic Musculoskeletal Pain.

The relationship between sarcopenia and pain remains unclear; thus, this study evaluated whether muscle strength is independently associated with neuropathic-like pain symptoms in patients with chronic musculoskeletal pain. A cut-off score of painDETECT ≥13 was used to indicate a possible neuropathic component. Handgrip strength was measured, and muscle mass was estimated. A total of 2599 patients, including 439 patients who reported neuropathic-like pain symptoms (16.9%), were included for analysis. Handgrip strength was significantly lower in patients experiencing neuropathic-like pain symptoms (23.23 ± 10.57 vs. 24.82 ± 10.43 kg, p < 0.001), and this result was chiefly found in female patients. However, there was no difference in estimated muscle mass. Shorter duration of pain, opioid usage, pain in lower limbs, sleep disturbance, and lower handgrip strength were significantly associated with neuropathic-like pain symptoms. In patients with handgrip strength below the reference values by sex, experiencing radiating pain and at least moderate sensory symptoms by light touch and thermal stimulation were more frequently reported. In conclusion, lower handgrip strength appeared to be an independent factor associated with symptoms suggestive of neuropathic pain in this population. Interventional studies are required to determine whether improvement in muscle strength can reduce the neuropathic pain component in chronic musculoskeletal pain.

Influence of cross-sectional area and fat infiltration of paraspinal muscles on analgesic efficacy of epidural steroid injection in elderly patients.

BACKGROUND: An assessment of paraspinal muscle degeneration based on magnetic resonance imaging has been used to investigate both sarcopenia and myosteatosis. The morphologic changes in cross-sectional area and fat infiltration of the paraspinal muscles can affect pain outcomes after epidural steroid injection. METHODS: Patients ≥65 years of age who underwent fluoroscopy-guided lumbar epidural steroid injections were enrolled. Good analgesia was defined as ≥50% reduction in pain score at 4 weeks after injection. Cross-sectional area and grade of fat infiltration of the paraspinal muscles on magnetic resonance images at the level of L3-L4 disc were measured. Patient demographics, pain-related factors, clinical factors, and paraspinal muscle measurements were compared between good and poor analgesia groups. The factors associated with pain outcomes after injection were identified using multivariate analysis. RESULTS: A total of 245 patients consisting of 149 and 96 patients in the good and poor analgesia groups, respectively, fully satisfied the study criteria for analysis. Patients of older age, opioid use, and high-grade foraminal stenosis were frequently observed in the poor analgesia group. The grade of fat infiltration of the paraspinal muscles was significantly higher in the poor analgesia group (Grade 2, 20.8% vs. 42.7%, p < 0.001), and this result was predominantly observed in female patients. However, there was no difference in the muscle cross-sectional area between the two groups (18.29 ± 3.16 vs. 18.59 ± 3.03 cm2 /m2 , p = 0.460). The percentage of patients with good analgesia decreased as the grade of fat infiltration increased (Grade 0 = 75.0%, Grade 1 = 65.8%, Grade 2 = 43.0%, p < 0.001). Multivariate logistic regression analysis revealed that preinjection opioid use [adjusted odds ratio (aOR) = 1.926, 95% confidence interval (CI) = 1.084-3.422, p = 0.025], moderate to severe foraminal stenosis (aOR = 2.859, 95% CI = 1.371-5.965, p = 0.005), and high-grade fat infiltration of the paraspinal muscles (aOR = 4.258, 95% CI = 1.805-10.043, p = 0.001) were significantly associated with poor analgesia after injection. CONCLUSION: High fat infiltration of the paraspinal muscles at the mid-lumbar region appeared to be an independent factor associated with poor analgesia after epidural steroid injection in elderly patients with symptomatic degenerative lumbar spinal disease receiving conservative care. However, the cross-sectional area of the paraspinal muscles was not associated with pain relief after injection.

Influence of needle-insertion depth on epidural spread and clinical outcomes in caudal epidural injections: a randomized clinical trial.

BACKGROUND: A caudal epidural steroid injection (CESI) is a commonly used method to improve symptoms of lumbosacral pain. We compared the achievement of successful epidurograms and patient-reported clinical outcomes following different needle-insertion depths during CESI. METHODS: For the conventional method group, the needle was advanced into the sacral canal. For the alternative method group, the needle was positioned immediately after penetration of the sacrococcygeal ligament. Epidural filling patterns and vascular uptake during fluoroscopy were determined to verify successful epidural injection. Procedural pain scores were investigated immediately after the procedure. Pain scores and patient global impression of symptom change were evaluated at 1-month follow-up. RESULTS: Assessments were completed by 127 patients (conventional method, n=64; alternative method, n=63). The incidence of intravascular injection was significantly lower in the alternative method group than in the conventional method group (3.2% vs 20.3%, P=0.005). Procedural pain during needle insertion was significantly lower in the alternative method group (3.7±1.3 vs 5.3±1.2, P<0.001). Epidural contrast filling patterns were similar in both groups. One-month follow-up pain scores and patient global impression of symptom change were comparable in both groups. CONCLUSION: Compared with the conventional method, the alternative method for CESI could achieve similar epidural spread and symptom improvement. The alternative technique exhibited clinical benefits of a lower rate of intravascular injection and less procedural pain.

Predictors of the analgesic efficacy of pulsed radiofrequency treatment in patients with chronic lumbosacral radicular pain: a retrospective observational study.

BACKGROUND: Pulsed radiofrequency (RF) targeting the adjacent dorsal root ganglion (DRG) is one treatment option for lumbosacral radicular pain. However, the analgesic efficacy of this procedure is not always guaranteed. The aim of this retrospective study was to identify the predictors of the analgesic efficacy of pulsed DRG RF treatment in patients with chronic lumbosacral radicular pain. METHODS: Patients who underwent pulsed DRG RF treatment from 2006 to 2017 at our clinic were enrolled. Positive response was defined as a ≥50% reduction in pain score from baseline at day 30. Patient demographics, pain-related factors, and clinical factors were evaluated using logistic regression analysis to identify the predictors of a positive response to the treatment. RESULTS: A total of 60 patients satisfied the study protocol requirements. Twenty-eight patients (46.7%) had a positive outcome. Multivariate logistic regression analysis revealed that the absence of comorbid musculoskeletal pain (OR=0.518, 95% CI=0.029-0.858, P=0.033) and positive response to previous epidural steroid injection (OR=3.269, 95% CI=1.046-10.215, P=0.042) were independent predictors of the analgesic efficacy of pulsed DRG RF treatment. CONCLUSION: Comorbid musculoskeletal pain and previous epidural injection response appear to affect the outcome of pulsed DRG RF treatment in patients with chronic lumbosacral radicular pain.

Cadaveric Evaluation of Different Approaches for Quadratus Lumborum Blocks.

Background: A quadratus lumborum (QL) block is an abdominal truncal block technique that primarily provides analgesia and anaesthesia to the abdominal wall. This cadaveric study was undertaken to compare the dye spread between different needle approaches for ultrasound-guided QL blocks in soft-embalmed cadavers. Methods: After randomization, an experienced anesthesiologist performed two lateral, three posterior, and five alternative QL blocks on the left or right sides of five cadavers. The target injection point for the alternative approach was the lumbar interfascial triangle, same as that of conventional posterior QL block, with a different needle trajectory. For each block, 20 ml of dye solution was injected. The lumbar region and abdominal flank were dissected. Results: Ten blocks were successfully performed. Regardless of the approach used, the middle thoracolumbar fascia was deeply stained in all blocks, but the anterior layer was less stained. The alternative approach was more associated with spread of injectate to the transversus abdominis and transversalis fascia plane. Despite accurate needle placement, all lateral QL blocks were associated with a certain amount of intramuscular or subcutaneous infiltration. Two posterior QL blocks showed a deeply stained posterior thoracolumbar fascia, and one of them was associated with obvious subcutaneous staining. The subcostal, iliohypogastric, and ilioinguinal nerves were mostly involved, but the thoracic paravertebral space and lumbar plexus were not affected in all blocks. Conclusions: The alternative approach for QL blocks was able to achieve a comparable extent when compared to the conventional approach.

Predictors of analgesic efficacy of neurolytic celiac plexus block in patients with unresectable pancreatic cancer: the importance of timing.

BACKGROUND: Neurolytic celiac plexus block (NCPB) is a safe and effective method for reducing abdominal cancer pain. However, the analgesic efficacy of NCPB is not always guaranteed. The aim of this retrospective study was to identify predictors for the analgesic efficacy of NCPB in patients with unresectable pancreatic cancer. METHODS: Patients with unresectable pancreatic cancer who underwent NCPB from 2006 to 2015 were enrolled. Good analgesia after NCPB was defined as ≥ 50% reduction in pain score at day 30. Patient demographics, cancer characteristics, and pain-related factors were evaluated using a logistic regression analysis to identify predictors for good analgesia after NCPB. Additionally, survival outcomes were compared between patients with poor and good analgesia after NCPB. RESULTS: A total of 112 patients satisfied the study protocol requirements. Forty-seven patients (41.9%) showed good analgesia after NCPB. Better performance status, lower serum CA 19-9 level, shorter pain duration, and lower opioid dose were observed in patients with good analgesia after NCPB. Good performance status (ECOG performance status 1 vs. 2 or 3, OR = 2.737, 95% CI = 1.149 to 6.518, P = 0.023) and low daily opioid use (< 150 vs. ≥ 150 mg, OR = 2.813, 95% CI = 1.159 to 6.831, P = 0.022) before NCPB were independent predictors of good analgesia after NCPB. The median survival was significantly lower for patients with poor analgesia after NCPB (68 vs. 150 days, P < 0.001). CONCLUSION: NCPB should be offered early to selected patients to improve its analgesic efficacy in advance of deterioration from disease and pain in this population.

Comparison of Incidences of Intravascular Injection between Medial and Lateral Side Approaches during Traditional S1 Transforaminal Epidural Steroid Injection.

Purpose. Intravascular injection rates are higher during traditional S1 transforaminal epidural steroid injection (TFESI) compared with lumbar transforaminal injection. We compared the incidences of intravascular injection between the medial and lateral approaches to the S1 foramen during S1 TFESI. Materials and Methods. A total of 139 patients underwent one or more TFESIs (170 total injections). The patients received S1 TFESI by either medial or lateral side of S1 foramen under fluoroscopic anteroposterior view using digital subtraction method. The intravascular injection rates, epidural spread patterns, and contrast volumes required to reach the superior aspect of the L5-S1 intervertebral disc (SIVD) were compared between groups. Results. Intravascular injection rates during S1 TFESI were significantly lower in the medial approach compared with the lateral approach patients (4.9% versus 38.6%, resp., P < 0.001). The medial approach group had more epidural spread to the L5-S1 SIVD than the lateral group (82.1% versus 58.8%, resp.); lower contrast volume amounts were required to extend the L5-S1 SIVD (1.46 ± 0.48 versus 1.90 ± 0.62, resp.). Conclusion. During S1 TFESI, approaching the needle towards the medial part of the S1 foramen may reduce intravascular injection risk.

Botulinum Toxin Treatment for Nocturnal Calf Cramps in Patients With Lumbar Spinal Stenosis: A Randomized Clinical Trial.

OBJECTIVES: To evaluate the clinical effectiveness of botulinum toxin (BTX) injection into the gastrocnemius muscles in patients with lumbar spinal stenosis (LSS) who have frequent nocturnal calf cramps (NCCs). DESIGN: Prospective, randomized clinical trial. SETTING: Outpatient department for interventional pain management. PARTICIPANTS: Patients (N=50) with LSS who have NCCs at least once per week were enrolled. INTERVENTION: Patients were randomly allocated to receive either conservative treatments plus gabapentin (group GPN) or BTX injection (group BTX). MAIN OUTCOME MEASURES: We assessed back/leg pain intensity, the frequency and severity of NCCs, insomnia severity, and functional disability at baseline and after 2 weeks, 1 month, and 3 months. Additionally, Patient Global Impression of Change was assessed. RESULTS: Forty-five patients completed all assessments (group GPN, n=21; group BTX, n=24). Compared with group GPN, leg pain intensity, cramp frequency, and cramp severity were significantly decreased in group BTX at all follow-up visits (all, P<.01). Also, insomnia significantly improved in group BTX at the 2-week (P=.018) and 1-month follow-up (P=.037). Functional disability significantly improved in group BTX at 2 weeks' follow-up (P=.041). At the 3-month follow-up, patients in group BTX reported a higher impression of improvement for NCC symptoms than did those in group GPN (P<.001). A mean dose of 642.8mg of gabapentin was given daily in group GPN, but 7 patients (33.3%) reported systemic side effects. There were no serious complications related to BTX use. CONCLUSIONS: BTX treatment appears to be effective and safe for NCCs in symptomatic LSS patients receiving conservative care.

The Effect of Skin Pressure on Needle Entry Point Accuracy During Fluoroscopically Guided Lumbar Transforaminal Epidural Injections: A Randomized Clinical Trial.

OBJECTIVE: The aim of this study was to investigate the effect of skin pressure on needle entry point accuracy during fluoroscopically guided lumbar transforaminal epidural injection. DESIGN: This study is a prospective randomized clinical trial; 64 patients with a body mass index of 25 kg/m or greater were enrolled. For patients in the pressing group, the operator marked the needle entry point on the patient's back while pressing the patient's skin with the tip of an indicator. For patients in the nonpressing group, the tip of the indicator was gently positioned on the patient's skin. The data related to technical performance and radiation exposure during the procedure were compared. RESULTS: Sixty patients (nonpressing group, n = 30; pressing group, n = 30) were analyzed. There were more attempts to reposition the needle (n) and increased procedure time (in seconds) in the pressing group (median, 5 vs. 4 [P = 0.019]; 400.0 vs. 358.5 [P = 0.033]). The fluoroscopy time (in seconds) and the kerma-area product (in cGy cm) were also significantly longer and greater in the pressing group, respectively (median, 63.5 vs. 50.5 [P = 0.038]; 416.3 vs. 318.6 [P = 0.014]). CONCLUSIONS: This study shows that practitioners should not press the skin with a radiopaque indicator when determining the needle entry point by fluoroscopy during lumbar transforaminal epidural injection.

Factors Associated with Higher Reported Pain Levels in Patients with Chronic Musculoskeletal Pain: A Cross-Sectional, Correlational Analysis.

BACKGROUND: Chronic musculoskeletal pain is highly prevalent, disabling, and costly, and has many negative effects on quality of life. The aim of this study was to investigate factors associated with higher reported pain levels in patients with chronic musculoskeletal pain among demographic, clinical, and psychological factors, and to evaluate whether insomnia is independently associated with pain intensity in this population. METHODS: A total of 357 patients with chronic musculoskeletal pain (pain duration ≥ six months) satisfied the study inclusion criteria and were included in the analyses. Patient demographics, clinical, and psychological factors were evaluated with hierarchical multivariate logistic analysis to identify factors associated with severe pain (NRS [numeric rating scale] ≥ 7). Hierarchical linear regression analysis also performed to identify factors associated with pain intensity (0 to 10 NRS). RESULTS: Multivariate logistic analyses revealed older age (OR [odds ratio] = 1.017, 95% CI [confidence interval] 1.001-1.032, P = 0.034), high anxiety level (OR = 1.162, 95% CI 1.020-1.324, P = 0.024), high pain catastrophizing (OR = 1.043, 95% CI 1.007-1.081, P = 0.018), and severe insomnia (OR = 1.112, 95% CI 1.057-1.170, P<0.001) were significantly associated with severe pain. Hierarchical linear regression analysis showed age (ß = 0.106, P = 0.041), pain catastrophizing (ß = 0.249, P<0.001), and insomnia (ß = 0.286, P<0.001) were significantly associated with pain intensity. The variance in pain intensity explained by the final model was 32.2%. CONCLUSIONS: Older age, severe insomnia, and high pain catastrophizing were significantly associated with higher reported pain levels. Insomnia was independently associated with pain intensity, even after controlling for various demographic and clinical factors. These factors should be considered when devising pain management strategies for this population.

Factors associated with increased risk for pain catastrophizing in patients with chronic neck pain: A retrospective cross-sectional study.

Pain catastrophizing is becoming increasingly recognized as a clinically important psychological factor in chronic musculoskeletal pain. In this retrospective cross-sectional study, we have identified factors associated with an increased risk for pain catastrophizing in chronic neck pain (CNP) patients. We obtained data from our medical database on 331 patients who were treated for neck pain as their chief complaint at our clinic. The Pain Catastrophizing Scale (PCS) was used to define a high pain catastrophizing state (PCS score ≥21) in this study. Patient demographics, pain-related factors, and psychological factors were evaluated with logistic regression analysis to identify risk factors of high pain catastrophizing among patients with CNP. A total of 256 patients with CNP satisfied the study inclusion criteria and were included in the analyses. The median PCS score was 16 (range, 0-45), and 86 of 256 patients (33.5%) reported a PCS score ≥21. In multivariate analysis, high pain intensity, clinical insomnia, and a high level of depression/anxiety were strongly associated with high pain catastrophizing in patients with CNP. Depression was the strongest predictor of high pain catastrophizing, with an odds ratio of 7.35 (95% confidence interval 2.23-24.22). High pain catastrophizing was not significantly related to age, gender, comorbidities, or neck pain-related physical symptoms. In conclusion, poor psychological states should be addressed as an important part of pain management in CNP patients who are susceptible to high pain catastrophizing.

Clinical Effectiveness of Ultrasound-guided Costotransverse Joint Injection in Thoracic Back Pain Patients.

Because of its anatomical location and function, the costotransverse (CTRV) joint can be a source of thoracic back pain. In this retrospective observational study, we evaluated the clinical effectiveness of the CTRV joint injection in thoracic back pain patients with suspected CTRV joint problems. We enrolled 20 thoracic back pain patients with localized tenderness that was provoked by the application of pressure on the affected CTRV joints. We injected it with 0.5 ml of a ropivacaine and triamcinolone mixture at each level. The mean pre-injection pain score decreased by 37.9% (7.2 ± 1.5 to 4.5 ± 1.7, P < 0.001) two weeks after CTRV joint injection. In addition, 70% of patients reported an excellent or good level of satisfaction. We demonstrated that an ultrasound-guided injection of the CTRV joint reduced patients' pain scores and led to a high level of satisfaction at short-term follow-ups in patients with suspected CTRV joint problems.

Ultrasound-Guided Quadratus Femoris Muscle Injection in Patients with Lower Buttock Pain: Novel Ultrasound-Guided Approach and Clinical Effectiveness.

BACKGROUND: The quadratus femoris (QF) muscle is a possible source of lower buttock pain as evidenced by what is known about the pathophysiology of ischiofemoral impingement syndrome. However, there are few reports about the interventional management of the QF muscle as a pain generator. OBJECTIVE: To describe an ultrasound-guided QF muscle injection technique in patients with lower buttock pain suspected of QF muscle pathology and to report the result of treatment. STUDY DESIGN: Retrospective evaluation. SETTING: Outpatient department for interventional pain management at a university hospital. METHODS: We studied 14 patients who had deep tenderness localized to the lower buttock region at a point halfway between the lateral prominence of the greater trochanter and the ischial tuberosity corresponding to the location of the QF muscle belly. Under ultrasound guidance, 8 mL of 0.25% lidocaine was injected into the QF muscle. Pain scores were assessed prior to the first injection and 2 weeks after the last injection. Patient satisfaction was also assessed. RESULTS: When compared before and 2 weeks after last QF muscle injection, the mean pain score decreased by 49.3% (6.7 ± 2.3 to 3.4 ± 2.1, P < 0.001). Two weeks after the last injection, approximately 70% of patients (10 of 14 patients) expressed their satisfaction as excellent or good and the average frequency of injection was 2.5 times. There were no complications observed. LIMITATIONS: The results of this study should be considered preliminary owing to the small sample size and lack of a control group, and the retrospective characteristics of this study may have introduced a selection bias. CONCLUSIONS: Ultrasound-guided QF muscle injection with local anesthetic helps alleviate pain in patients with lower buttock pain attributed to the QF muscle, and leads to high levels of satisfaction for patients. A randomized placebo-controlled trial should be considered in the future.

Factors Associated with Increased Risk for Clinical Insomnia in Patients with Postherpetic Neuralgia: A Retrospective Cross-Sectional Study.

OBJECTIVE: To determine the risk factors associated with clinical insomnia in postherpetic neuralgia (PHN) patients. DESIGN: A retrospective cross-sectional study. SETTING: Outpatient department for interventional pain management at a university hospital. SUBJECTS: A total of 111 patients with PHN satisfied the study inclusion criteria and were included in the analyses. METHODS: The Insomnia Severity Index (ISI) was used to determine the presence of clinical insomnia (ISI score ≥ 15). Patient demographics, pain-related factors, and rash severity and location were evaluated with logistic regression analysis to identify risk factors of clinical insomnia among patients with PHN. RESULTS: In total, 50.5% of patients reported mild to severe insomnia symptoms (ISI score ≥ 8) after pain development. Moderate to severe clinical insomnia (ISI score ≥ 15) was observed in 30.6% of PHN patients. Multivariate logistic regression analyses revealed that high pain intensity was the strongest predictor of clinical insomnia (odds ratio (OR) = 12.417, 95% confidence interval (CI): 2.990-51.561, P = 0.001). However, presence of mechanical allodynia (OR = 4.263, 95% CI: 1.040-17.481, P = 0.034) and high anxiety and depression level (OR = 4.452, 95% CI: 1.201-16.508, P = 0.026; OR = 6.975, 95% CI: 1.425-34.138, P = 0.017) were also significantly associated with clinical insomnia after adjusting for pain score. Clinical insomnia was not significantly related to age, gender, rash severity, or location of skin lesion. CONCLUSIONS: Insomnia should be addressed as an important part of pain management in PHN patients with these risk factors, especially in patients with severe pain.