Osteoarthritis (OA) of the knee is an increasing problem in an aging population and many patients turn to various types of injection therapies to avoid surgery or strong medications. While interventional pain specialists claim the injections help to relieve pain and disability associated with knee OA, current evidence suggests that these therapies may be largely ineffective, somewhat costly, and possibly even cause harm in some cases.
Writing in the Annals of Internal Medicine, Anne Rutjes, PhD, of the University of Bern in Switzerland, and colleagues report conducting a systematic review and meta-analysis of studies examining viscosupplementation — the intra-articular injection of hyaluronic acid — for symptomatic relief of painful knee OA in adults [Rutjes et al. 2012]. Hyaluronic acid is a lubricant in joint fluid that acts like a shock absorber, but declines with the wear-and-tear of osteoarthritis. An improved form, cross-linked hyaluronic acid, has higher molecular weight that enhances its elastoviscous properties and provides a longer period of residence in the joint space (ie, slower resorption).
The ever-increasing numbers of unregulated products from the dietary supplement industry have considerable potential to complicate safe and effective pain care, as well as causing health problems of their own. Clinicians and patients need to be wary of possible consequences posed by the seemingly innocuous supplements that line pharmacy and retail store shelves and fill the pages of countless websites on the Internet.
An excellent review article by Edward W. Boyer, MD, PhD, in the New England Journal of Medicine discusses the management of life-threatening overdose from opioid analgesics [Boyer 2012]. He describes essential principles and practices that every healthcare provider, as well as educated patients, absolutely must know about — including some surprising revelations.
By guest author Lynn Webster, MD, at the LifeSource Blog 
Changes in the formulations of OxyContin and Opana, making them less subject to misuse, ironically have former abusers of those drugs turning to deadly heroin, according to reports in the New England Journal of Medicine and USA Today. Meanwhile, as another unintended consequence, some patients with chronic pain say the newly formulated opioids do not work for them as well as before.
In a long-expected, but rather anticlimactic, announcement, the U.S. Food and Drug Administration (FDA) approved a shared Risk Evaluation and Mitigation Strategy (REMS) for all extended-release (ER) and long-acting (LA) opioid analgesics. This program has been in the works for more than 3 years and is a prudent, but possibly inadequate, step in the right direction.
As regular readers of these Pain-Topics UPDATES know, we have long advocated for the potential benefits of adequate vitamin D in persons with chronic pain conditions of various types. Recent research studies shed more light on the advantages as well as some concerns about vitamin D supplementation that are of importance for clinicians and patients.
According to newly released reports from the U.S. Centers for Disease Control and Prevention (CDC), the synthetic opioid methadone accounts for less than 2% of analgesic prescriptions but is involved in more than 30% of opioid-overdose deaths. However, in some ways, the selective analysis and presentation of data may be misleading.
Featured Items: pregabalin (Lyrica) approved for neuropathic pain in spinal cord injury; gabapentin enacarbil (Horizant) approved for postherpetic neuralgia; OPANA ER conversion to crush-resistant tablets; supplement Reumofan-Plus recalled for undeclared drugs. 
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