Chronic pain is a significant social issue, causing suffering, reducing quality of life, hindering employment, and increasing societal medical costs. The multidisciplinary pain clinic, initiated by John Bonica at the University of Washington in 1960 and incorporating the biopsychosocial model in the 1980s, has become a cornerstone of chronic pain management. This approach has spread to Western countries, fostering the establishment of multidisciplinary pain centers as part of chronic pain policies. In Japan, the Ministry of Health, Labour and Welfare has promoted these centers since 2009. These centers offer comprehensive care through multi-professional collaboration based on the biopsychosocial model. This paper provides a narrative review of multidisciplinary treatment for chronic pain, the biopsychosocial model, and the functions of pain centers in regional healthcare, focusing on their historical development and significance. Over the past half-century, literature indicates that the multidisciplinary approach in pain centers will continue to play a pivotal role in chronic pain management and the advancement of pain medicine.

Peripheral neuropathic pain (PNP) other than diabetic peripheral neuropathic pain (DPNP)/postherpetic neuralgia (PHN) was not the target population in clinical trials of mirogabalin (Tarlige^®). To assess the effectiveness of mirogabalin for other types of PNP, this multicenter, prospective, observational study evaluated the effectiveness of mirogabalin in patients with DPNP/PHN (n＝529) and in those with other types of PNP (n＝1,029) in real-world clinical settings. The rate of patients with ≥50％ reduction in pain visual analog scale (VAS) scores was not significantly different between the groups (45.6％ in the DPNP/PHN group and 48.7％ in the other PNP group; median odds ratio [95％ credible interval]: 1.134 [0.919, 1.401]). The overall incidence of adverse drug reactions (ADRs) was 9.08％ (DPNP/PHN 8.63％，other PNP 9.29％). The most common ADRs were dizziness and somnolence, which are expected events with mirogabalin. Given these results, mirogabalin seems effective for other types of PNP. And there were no new safety concerns with mirogabalin in this study.

Pulsed radiofrequency (PRF) is a treatment method that relieves pain by intermittently applying radio frequency waves to nerve tissue. Unlike radiofrequency thermocoagulation, this method not only can be applied to nerves including motor nerves, but can also be expected to have a therapeutic effect by acting on peripheral nerve axons, so it has the advantage of being widely applicable. Last year, the latest PRF generators were introduced in Japan as well as equipment overseas. PRF has 4 types of frequencies (1, 2, 5, 10 Hz), 5 types of pulse widths (5, 10, 20, 30, 50 msec), A generator was introduced that allows the voltage to be changed arbitrarily from 20 V to 70 V. This article provides an overview of pulsed radiofrequency therapy, the latest equipment, treatments using the latest parameters, and mechanism of action of PRF. In the future, it is hoped that Japan will take the initiative in developing PRF and conducting clinical research.

Bladder pain syndrome is a disorder characterized by pelvic pain and urological symptoms, such as frequent urination and increased urinary urgency, with no identifiable organic cause. The exact etiology is unknown, and no definitive treatment is available. A 59-year-old woman experienced pubic discomfort for five months, accompanied by intense pubic pain and urinary urgency. She was referred to our hospital after receiving treatment at several medical institutions, and none of her symptoms improved. She had persistent needle-like pain from the vulva to the perianal area accompanied by allodynia. Her treatment included pregabalin for pelvic pain and traditional Japanese Kampo medicine for urinary urgency. As a psychosocial evaluation revealed depression, anxiety, pain catastrophizing, and decreased daily activity, acceptance and commitment therapy with cognitive-behavioral therapy was introduced. Following treatment initiation, the patient's persistent pain and urological symptoms improved. Multidisciplinary therapy in line with the chronic pain treatment strategy may be effective for refractory bladder pain syndrome.

Intrathecal analgesia is a useful treatment for cancer pain. However, there are few reports of its use at the cervical spinal cord level, and we need to be careful about the risk of total spinal paresis and respiratory depression. 50-year-old woman complained of swelling and pain in the left upper extremity due to axillary lymph node recurrence after left breast cancer surgery. Since pain control with opioids was poor, we decided to perform intrathecal analgesia. A catheter was placed at the level of the inferior margin of C7, and a port was created in the left upper abdomen. Morphine and bupivacaine were started at 0.3 mg/day and 2.4 mg/day, respectively. On the 13th postoperative day, the dosage was increased to 6 mg/day and 12 mg/day, and the NRS improved from 9 to 2. No serious side effects occurred during the procedure. Because serious side effects can occur with intrathecal analgesia at the cervical level, the dosage regimen should be carefully adjusted.

An 80-year-old male with cancer pain due to pancreatic cancer underwent splanchnic nerve block twice to manage abdominal and lower back pain. Due to persistent pain, an intrathecal catheter and a subcutaneous access port (intrathecal port, IT port) were placed for continuous analgesic administration. Intrathecal morphine was initiated at a dose of 1.2 mg/day. The patient was discharged five days after IT port placement. Three days post-discharge, he was visited by the pain management team due to increasing pain. At this time, the intrathecal morphine dose was increased to 6.0 mg/day. The patient passed away peacefully and painlessly at home, seven days after discharge. Intrathecal analgesia is a valuable technique for delivering neuraxial analgesia in a home setting. We report a case in which the patient was able to remain at home while receiving weekly management of intrathecal analgesia by our staff, in conjunction with general home medical care provided by a visiting physician.