Accepted

The study objective was to determine whether burrowing behavior is useful as a functional index of pain in both male and female rats, and whether a 'no-training' protocol can be used to increase testing efficiency. Adult Sprague-Dawley rats were injected in one or both hindpaws with oil vehicle or complete Freund's adjuvant (CFA); starting the next day, the amount of gravel each rat burrowed out of a tube in 1 h was measured daily for ≤7 days. Without preliminary training on the burrowing procedure, CFA reliably suppressed burrowing for 2-3 days compared to controls, in both sexes. However, whereas unilateral CFA completely suppressed burrowing 1-day post-CFA in nearly all males, bilateral CFA was required to do so in females. When administered 30 min before testing, once daily for 5 days post-CFA, the nonsteroidal anti-inflammatory drug ketoprofen (0.01-3.2 mg/kg) and the opioid morphine (0.1-3.2 mg/kg) significantly increased CFA-suppressed burrowing, whereas the purported cannabinoid analgesic Δ9-tetrahydrocannabinol (0.01-2.0 mg/kg) did not. The benzodiazepine chlordiazepoxide (1.25-10 mg/kg), included as a 'true negative' control, also did not restore CFA-suppressed burrowing in either sex. However, in CFA-treated males only, chlordiazepoxide decreased burrowing, suggesting that anxiety may contribute to burrowing in males but not females that are in pain. Overall these results suggest that burrowing is a valid, functional index of inflammatory pain in both sexes, and training on the burrowing procedure is not necessary. However, females are more avid burrowers than males, which should be considered when both sexes are used in inflammatory pain testing.

Pulsed radiofrequency (PRF) is an efficacious treatment for patients with lumbosacral radicular pain, but the optimal radiofrequency parameters are inadequately described. We hypothesized that high-voltage radiofrequency therapy around the dorsal root ganglion can be more effective and enduring than the standard voltage PRF therapy.

Post-traumatic stress disorder (PTSD) is a serious mental disease featured by a stress disfunction that occurs after an individual has faced intense mental stress, often accompanied by anxiety and chronic pain. Currently, the mainstream drug for PTSD is serotonin reuptake inhibitors (SSRIs), however, their pain management for patients is limited. Baicalein, a Chinese traditional herbal medicine. Has shown promising results in treating anxiety, depression, and pain. In this study, we found that baicalein may alleviate single prolonged stress (SPS)-induced PTSD-like behaviors in mice without altering baseline nociceptive sensitivity or activity. Meanwhile, baicalein increased the noradrenaline (NE) and serotonin (5-HT) content and decreased the ratio of 5-hydroxyindoleacetic acid (5-HIAA)/5-HT by inhibiting the activity of monoamine oxidase A (MAO-A) in SPS-induce mice. The anxiolytic and antinociceptive effects induced by baicalein were totally abolished by 5-HT depleting agents. Moreover, the anxiolytic effects of baicalein could be abolished by the 5-HT1A receptor antagonist WAY-100635, and the analgesic effects could be abolished by delta-opioid receptor antagonists in the spinal. Taken together, our study provides compelling evidence that baicalein reversed anxiety-like behaviors and neuropathic pain in PTSD through serotonergic system and spinal delta-opioid receptors.

Uptake of telehealth has surged, yet no previous studies have evaluated the clinimetric properties of clinician-administered performance-based tests of function, strength, and balance via telehealth in people with chronic lower limb musculoskeletal pain. This study investigated the: (i) test-retest reliability of performance-based tests via telehealth, and (ii) agreement between scores obtained via telehealth and in-person.

More than 10% of the world's population suffers from osteoarthritis (OA) of the knee, with a lifetime risk of 45%. Current treatments for knee OA pain are as follows: weight control; oral pharmacological treatment (non-steroidal anti-inflammatory drugs, paracetamol, opioids); mechanical aids (crutches, walkers, braces, orthotics); therapeutic physical exercise; and intraarticular injections of corticosteroids, hyaluronic acid, and platelet-rich plasma (PRP). The problem is that such treatments usually relieve joint pain for only a short period of time. With respect to intraarticular injections, corticosteroids relieve pain for several weeks, while hyaluronic acid and PRP relieve pain for several months. When the above treatments fail to control knee pain, total knee arthroplasty (TKA) is usually indicated; however, although a very effective surgical technique, it can be associated with medical and postoperative (surgery-related) complications. Therefore, it seems essential to look for safe and effective alternative treatments to TKA. Recently, there has been much research on intraarticular injections of mesenchymal stem cells (MSCs) for the management of OA of the knee joint. This article reviews the latest information on the molecular mechanisms of action of MSCs and their potential therapeutic benefit in clinical practice in patients with painful knee OA. Although most recent publications claim that intraarticular injections of MSCs relieve joint pain in the short term, their efficacy remains controversial given that the existing scientific information on MSCs is indecisive. Before recommending intraarticular MSCs injections routinely in patients with painful knee OA, more studies comparing MSCs with placebo are needed. Furthermore, a standard protocol for intraarticular injections of MSCs in knee OA is needed.