The effects of TENS, interferential stimulation, and combined interferential stimulation and pulsed ultrasound on patients with disc herniation-induced radicular pain.

BACKGROUND: Electrotherapy is part of a physician's toolbox for treating various musculoskeletal conditions, including radicular pain, but the preferred modality is yet unclear. OBJECTIVE: To compare the short-term efficacy of three electrotherapeutic modalities in relieving lumbar disc herniation (LDH)-induced radicular pain. METHODS: Fourteen patients with LDH-induced radicular pain attended a single session of electrotherapy, which included four 10-min consecutive treatments: transcutaneous electrical nerve stimulation (TENS), interferential (IF) stimulation, a combined treatment with pulsed ultrasound and IF current (CTPI), and a sham control. Treatments were randomized and the straight leg raise (SLR) degree was measured immediately before and after each treatment. RESULTS: Each of the three active modalities significantly improved the SLR score. The most prominent improvement was observed in the CTPI condition, followed by IF and, finally, TENS. The sham stimulation did not affect the SLR scores. CONCLUSIONS: A single session with either TENS, IF current or CTPI is sufficient to improve the range of motion and degree of radicular pain associated with LDH. CTPI appears to be the most effective modality of the three, possibly due to greater penetration efficiency of the induced current. The effects of a long-term treatment schedule are yet to be identified.

Medical cannabis treatment for chronic pain: Outcomes and prediction of response.

BACKGROUND: Although studied in a few randomized controlled trials, the efficacy of medical cannabis (MC) for chronic pain remains controversial. Using an alternative approach, this multicentre, questionnaire-based prospective cohort was aimed to assess the long-term effects of MC on chronic pain of various aetiologies and to identify predictors for MC treatment success. METHODS: Patients with chronic pain, licensed to use MC in Israel, reported weekly average pain intensity (primary outcome) and related symptoms before and at 1, 3, 6, 9 and 12 months following MC treatment initiation. A general linear model was used to assess outcomes and identify predictors for treatment success (≥30% reduction in pain intensity). RESULTS: A total of 1,045 patients completed the baseline questionnaires and initiated MC treatment, and 551 completed the 12-month follow-up. At 1 year, average pain intensity declined from baseline by 20% [-1.97 points (95%CI = -2.13 to -1.81; p < 0.001)]. All other parameters improved by 10%-30% (p < 0.001). A significant decrease of 42% [reduction of 27 mg; (95%CI = -34.89 to 18.56, p < 0.001)] from baseline in morphine equivalent daily dosage of opioids was also observed. Reported adverse effects were common but mostly non-serious. Presence of normal to long sleep duration, lower body mass index and lower depression score predicted relatively higher treatment success, whereas presence of neuropathic pain predicted the opposite. CONCLUSIONS: This prospective study provides further evidence for the effects of MC on chronic pain and related symptoms, demonstrating an overall mild-to-modest long-term improvement of the tested measures and identifying possible predictors for treatment success.

Depression level, not pain severity, is associated with smoked medical marijuana dosage among chronic pain patients.

BACKGROUND: The use of medical marijuana (MM) for the treatment of chronic pain is rapidly growing in the United States and Europe; however there is concern regarding the specificity of its therapeutic effects and the motivation underlying its use. While research indicates that among chronic pain prescribed opioids, depression has been associated with increased opioid dosage (regardless of pain levels), the extent to which depression and pain each contribute to MM dose among chronic pain patients is yet unknown. METHODS: This cross-sectional study included 209 chronic pain patients prescribed smoked MM, in flower or other plant form, with no concurrent opioid treatment. Ordinal regression analyses were performed in order to explore the unique contribution of mean pain level (1-10 scale), depression severity (measured by the Patient Health Questionnaire (PHQ-9)) and anxiety severity (measured by the Generalized Anxiety Disorder scale (GAD-7)) to doses of MM, while taking into account additional sociodemographic and clinical factors. RESULTS: Individuals with mild depression and those with moderate to severe depression were at significantly increased odds for using higher doses of MM in grams per month(Adjusted Odds Ratio(AOR) = 2.06,95% Confidence Interval(CI) = 1.05-4.01, and AOR = 5.95,95% CI = 1.97-17.98, respectively) compared to those without depression. In addition, individuals with mild depression were at significantly increased odds for smoking more MM joints daily(AOR = 2.07, 95% CI = 1.01-4.23) compared to individuals without depression. Mean levels of pain or anxiety severity were not significantly associated with either dose measures. CONCLUSIONS: Depression and MM dose are highly correlated and should be concurrently addressed during chronic pain treatment.

Efficiency of Tissue Penetration by Currents Induced by 3 Electrotherapeutic Techniques: A Comparative Study Using a Novel Deep-Tissue Measuring Technique.

BACKGROUND: Electrotherapy provides a wide range of treatment alternatives for musculoskeletal pathologies. However, for the electrical stimulation to exert a significant therapeutic effect, the induced current must often penetrate deep inside the target tissue. OBJECTIVE: The objective was to systematically compare the penetration efficiency of 3 electrotherapeutic stimulation modalities: transcutaneous electrical nerve stimulation (TENS), interferential (IF) stimulation, and combined therapy with pulsed ultrasound and IF current (CTPI). DESIGN: This was a comparative, experimental laboratory study. METHODS: The penetration efficiency was evaluated as a voltage difference between 2 of an 8-contact spinal cord stimulation array. Each of 20 participants with a preimplanted spinal cord stimulation array was stimulated with TENS (3 different electrode configurations), IF current (3 configurations), and CTPI (1 configuration). RESULTS: Significant differences in penetration efficiency were found between the various stimulation conditions and electrode configurations. CTPI showed the highest penetration efficiency, followed by IF, and finally TENS. Penetration efficiency was inversely and significantly correlated with skinfold thickness in all conditions, but this correlation was lowest for the CTPI stimulation. LIMITATIONS: Our study design did not include a condition of combined therapy with pulsed ultrasound and TENS, and it did not directly control for current or voltage density under the stimulating electrodes. In addition, further research is required to determine whether a higher stimulation intensity of the target tissue is advantageous clinically. CONCLUSIONS: Pending further testing, CTPI stimulation could prove more effective than IF and TENS in reaching deeper tissues, especially considering the variability in adipose tissue thickness in the population, for example, in cases of patients with obesity.

Depression and anxiety among chronic pain patients receiving prescription opioids and medical marijuana.

BACKGROUND: High rates of depression and anxiety have been consistently reported among patients suffering from chronic pain. Prescription opioids are one of the most common modalities for pharmacological treatment of pain, however in recent years medical marijuana(MM) has been increasingly used for pain control in the US and in several countries worldwide. The aim of this study was to compare levels of depression and anxiety among pain patients receiving prescription opioids and MM. METHODS: Participants were patients suffering from chronic pain treated with prescription opioids (OP,N=474), MM (N=329) or both (OPMM,N=77). Depression and anxiety were assessed using the depression module of the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder scale (GAD-7). RESULTS: Prevalence of depression among patients in the OP, MM and OPMM groups was 57.1%, 22.3% and 51.4%, respectively and rates of anxiety were 48.4%, 21.5% and 38.7%, respectively. After controlling for confounders, patients in the OP group were significantly more likely to screen positive for depression (Adjusted Odds Ratio(AOR)=6.18;95%CI=4.12-9.338) and anxiety(AOR=4.12;CI=3.84-5.71)) compared to those in the MM group. Individuals in the OPMM group were more prone for depression (AOR for depression=3.34;CI=1.52-7.34)) compared to those in the MM group. LIMITATIONS: Cross-sectional study, restricting inference of causality. CONCLUSIONS: Levels of depression and anxiety are higher among chronic pain patients receiving prescription opioids compared to those receiving MM. Findings should be taken into consideration when deciding on the most appropriate treatment modality for chronic pain, particularly among those at risk for depression and anxiety.