More than 20 percent of people in the United States, age 35 years or older, have complained of chronic knee pain. Many complain of multiple sites, making musculoskeletal pain a common complaint. On the other hand, many who don't have or complain of pain do have osteoarthritis but they don't know it, while yet others have minor disability but experience and complain of severe pain.

Chronic low back pain is increasingly common in the developed world. It is estimated that one quarter of those with low back pain visit their doctor for help, but most do not continue after three months, although 60 to 80 percent still have pain, even after one year.

Researchers have investigated psychological influences of back pain, trying to see if any of these factors made a difference in pain and, if so, how:

• fear avoidance
• catastrophizing

The issue of empathy has intrigued scientists and researchers and they have been trying to determine the impact of empathy on pain.

In light of recent studies that have demonstrated a connection between pain and observing someone else in pain, the authors of this article predicted that "the empathetic states would induce sensitization of cortical areas" involved in the perception of pain.

TENS, transcutaneous electrical nerve stimulation, is an increasingly popular non-medication pain treatment, but there has not yet been any definitive studies regarding its effect on chronic pain.

There are several causes of chronic pain, but the two mechanisms are muscle and joint tissue pain and nerve pain. The authors of this study examined the effects of TENS and if researchers could predict if high intensity TENS would be successful in patients with chronic pain.

Over the last 40 years, ankle joint replacements have gone through three generations of implant design and materials. In this article, a group of orthopedic surgeons review the history of total ankle arthroplasty (TAA) and bring us up to date on this treatment approach for ankle arthritis.

In this study, workers with occupational back pain are asked to rate their satisfaction with care based on who provided that care. Health care providers included surgeons, medical doctors, osteopathic physicians, chiropractors, and physical therapists.

Treatment for spinal fractures may be operative (surgery) or nonoperative (conservative care). Research comparing these two treatment methods is very limited. It's difficult to compare the results between these two interventions. For one thing, surgeons use different methods to classify the injury.

In this study, researchers analyze patient cases from a regional spinal cord injury center who suffered injuries from a fall out of a hunting tree stand. The intent of the study was to show how often this happens, what causes these types of injuries, and how to prevent them.

Although rare, a herniated disc can cause paralysis on one side of the body. The condition is called the Brown-Séquard syndrome. This is a case report of such an incident. Only 25 total cases have ever been reported.

Many people are familiar with carpal tunnel syndrome (CTS). Most often the condition is chronic with a gradual onset of pain, numbness, and tingling of the fingers, palm, and/or wrist. But sudden CTS can occur as a result of bone fracture, infection, snake bite, or other trauma.

Sudden, severe symptoms of CTS that develop over the course of a few hours (rather than weeks to months) is referred to as acute CTS. A rapid rise in pressure occurs inside the carpal tunnel.

Vertebral compression fractures (VCFs) can be treated with vertebroplasty or kyphoplasty. Comparing the results of these two procedures will help surgeons decide which procedure to use for each patient. In this study, 168 published articles on these treatment techniques were analyzed. The authors present a summary of the findings.

Patients who need a spinal fusion often donate bone graft material from their own iliac (pelvic) crest. This is called an autograft. It takes quite a while for the fusion to occur. Often there are complications at the donor site.

Orthopedic surgeons at the Mayo Clinic in Rochester, Minnesota compared speed of recovery in hip replacement patients. They used two different surgical approaches. Patients in both groups were similar in age, diagnosis, and background. Everyone was treated using the same advanced anesthetic and rehab protocols.

A group of orthopedic surgeons from Sweden started a study 25 years ago. They wanted to assess the results of nonoperative treatment for anterior shoulder dislocations. The patients in their study were all 40 years old or younger.

Most (80 per cent) were men. They all had their first anterior shoulder dislocation in 1978 or 1979. More than half were involved in a sports activity when the dislocation occurred.

Intrathecal injection of alcohol or phenol has been an effective pain management technique for patients who live with chronic pain. The injection damages the pain pathways, providing pain relief for up to several months. Although injection into the subarachnoid space can provide pain relief in up to 60 percent of patients, epidural injection is often preferred because of the side effects associated with subarachnoid injections.