RECENT QUALITATIVE SYSTEMatic review of the effectiveness of cannabinoids in the management of pain advised against their widespread introduction into clinical practice because of limited relative efficacy in acute pain and common adverse effects. 1 However, it was suggested that cannabinoids may have some beneficial effect in spasticity and in neuropathic pain, for which a therapeutic need is greater than in postoperative pain. In addition, the authors stated that new safe and effective agonists at the cannabinoid receptors may dissociate therapeutic effects from psychotropic effects, which makes randomized comparisons in neuropathic pain and spasticity worthwhile. 1 1Ј,1ЈDimethylheptyl-⌬ 8 -tetrahydrocannabinol-11-oic acid (CT-3) potentially possesses the efficacy to treat neuropathic pain and spasticity without the psychotropic liabilities of cannabis. CT-3 is a synthetic analog of tetrahydrocannabinol (THC)-11-oic acid, one of the endogenous transformation products of THC, in which a dimethylheptyl side chain is substituted for the pentyl side chain. 2 In preclinical studies, CT-3 was found to be a potent anti-inflammatory, analgesic, and antiallodynic agent

Both the discovery of the endocannabinoid system (ECS) and its role in the control of pain and habituation to stress, as well as the significant analgesic and antihyperalgesic effects in animal studies, suggest the usefulness of cannabinoids in pain conditions. However, in human experimental or clinical trials, no convincing reduction of acute pain, which may be caused by a pronociceptive, ECS-triggered mechanism on the level of the spinal cord, has been demonstrated. In contrast, in chronic pain and (painful) spasticity, an increasing number of randomized, double-blind, placebo-controlled studies have shown the efficacy of cannabinoids, which is combined with a narrow therapeutic index. Patients with unsatisfactory response to other methods of pain therapy and who were characterized by failed stress adaptation particularly benefited from treatment with cannabinoids. None of the attempts to overcome the disadvantage of the narrow therapeutic index, either by changing the route of application or by formulating balanced cannabinoid preparations, have resulted in a major breakthrough. Therefore, different methods of administration and other types of cannabinoids, such as endocannabinoid modulators, should be tested in future trials.

Auricular acupuncture can be an effective treatment for acute anxiety, but there is a lack of direct comparisons of acupuncture to proven standard drug treatments. In this study we compared the efficacy of auricular acupuncture with intranasal midazolam, placebo acupuncture, and no treatment for reducing dental anxiety. Patients having dental extractions (n = 67) were randomized to (i) auricular acupuncture, (ii) placebo acupuncture, and (iii) intranasal midazolam and compared with a no treatment group. Anxiety was assessed before the interventions, at 30 min, and after the dental extraction. Physiological variables were assessed continuously. With the no treatment group as control, the auricular acupuncture group, and the midazolam group were significantly less anxious at 30 min as compared with patients in the placebo acupuncture group (Spielberger Stait-Trait Anxiety Inventory X1, P = 0.012 and <0.001, respectively). In addition, patient compliance assessed by the dentist was significantly improved if auricular acupuncture or application of intranasal midazolam had been performed (P = 0.032 and 0.049, respectively). In conclusion, both, auricular acupuncture and intranasal midazolam were similarly effective for the treatment of dental anxiety.

Loss of inhibitory synaptic transmission within the dorsal horn of the spinal cord plays a key role in the development of chronic pain following inflammation or nerve injury. Inhibitory postsynaptic transmission in the adult spinal cord involves mainly glycine. Cannabidiol is a nonpsychotropic plant constituent of Cannabis sativa. As we hypothesized that non-CB receptor mechanisms of cannabidiol might contribute to its anti-inflammatory and neuroprotective effects, we investigated the interaction of cannabidiol with strychnine-sensitive α₁ and α₁β glycine receptors by using the whole-cell patch clamp technique. Cannabidiol showed a positive allosteric modulating effect in a low micromolar concentration range (EC₅₀ values: α₁ = 12.3 ± 3.8 μmol/l and α₁β = 18.1 ± 6.2 μmol/l). Direct activation of glycine receptors was observed at higher concentrations above 100 μmol/l (EC₅₀ values: α₁ = 132.4 ± 12.3 μmol/l and α₁β = 144.3 ± 22.7 μmol/l). These in vitro results suggest that strychnine-sensitive glycine receptors may be a target for cannabidiol mediating some of its anti-inflammatory and neuroprotective properties.

Physical, mental, and social well-being are part of the concept of health according to the World Health Organization, in addition to the absence of disease and infirmity. Therefore, for a full description of a person's health status, the International Classification of Functioning, Disability and Health (ICF) was launched in 2001 to complement the existing International Classification of Diseases (ICD). The 11th version of the ICD (ICD-11) is based on so-called content models, which have 13 main parameters. One of them is functioning properties (FPs) that, according to the WHO, consist of the activities and participation components of the ICF. Recently, chronic pain codes were added to the 11th edition of the ICD, and hence, a specific set of FPs for chronic pain is required as a link to the ICF. In addition, pain is one of the 7 dimensions of the generic set of the ICF, which applies to any person. Thus, assessment and management of pain are also important for the implementation of the ICF in general. This article describes the current consensus proposal by the International Association for the Study of Pain (IASP) and the International Society of Physical and Rehabilitation Medicine (ISPRM) for a specific set of FPs of chronic pain, which will have to be empirically validated in a next step. The combined use of ICD-11 and ICF is expected to improve research reports on chronic pain by a more precise and adequate coding, as well as patient management through better diagnostic classification.

In the treatment of chronic epicondylopathia lateralis humeri, acupuncture in which real acupuncture points were selected and stimulated was superior to non-specific acupuncture with respect to reduction in pain and improvement in the functioning of the arm. These changes are particularly marked at early follow-up.

Sixty-nine patients (mean age 48.1 years, SD = 14.1) fulfilling the International Headache Society criteria for tension-type headache were randomly assigned to verum or placebo condition. No significant differences between placebo and verum with respect to visual analogue scale and frequency of headache attacks could be observed immediately, 6 weeks and 5 months after the end of treatment. There was a significant but weak improvement in quality of life parameters (clinical global impressions, Nottingham Health Profile) after verum treatment. In decision tree analyses, the changes in clinical global impressions and headache frequency depended significantly on primary headache frequency with a limit value of 24.5 days headache per month. High values in the von Zerssen Depression Score resulted in high mean visual analogue scale values.

In order to examine the role of muscular mechanisms in chronic tension-type headache a study with needle acupuncture was performed. Needle acupuncture could be of therapeutic value because it has shown some positive effects in myofascial pain syndromes. We performed a double-blind, placebo-controlled study with 39 patients (mean age 49.0 years, SD=14.8) fulfilling the International Headache Society criteria for chronic tension-type headaches. Participants were randomly assigned to verum or placebo condition. Six weeks after end of treatment no significant differences between placebo and verum could be observed with respect to visual analogue scale and frequency of headache attacks. Nevertheless, pressure pain thresholds significantly increased for the verum group. The findings of our study support the hypothesis that peripheral mechanisms - such as increased muscle tenderness - only play a minor role in the pathogenesis of chronic tension-type headache.