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News In Brief
 Osteoporosis is blamed for backbone fractures. The real culprit could well be our own vertebrae, which evolved to absorb the pounding of upright walking, researchers at Case Western Reserve University say.
Compared to apes, humans have larger, more porous vertebrae encased in a much thinner shell of bone.
The design works well until men and women age and suffer bone loss, leaving them vulnerable to cracks and breaks, the scientists say. Apes, on the other hand, can suffer comparable bone loss as they age, but have much thicker vertebral shells to begin with so that their vertebrae remain intact.
The findings are now published in the online journal PLoS One.
“In evolution we have great adaptation, but there is sometimes a tradeoff,” said Meghan Cotter, an instructor in anatomy at Case Western Reserve University School of Medicine and a lead author of the study.
“The structure is great for walking around, but not good when you have osteoporosis,” she said.
The researchers took measurements and used CT scans, Micro CT scans and computer modeling to compare the size, shape, structure, microstructure, biomechanics and strength of the 8th thoracic vertebra from skeletons of humans, gorillas, chimpanzees and orangutans.
Reconstructive surgical approaches can help delay endoprosthetic joint replacement in patients with osteoarthritis. Henning Madry and coauthors introduce such procedures in the current issue of Deutsches Ärzteblatt International.
Articular cartilage defects often develop subsequent to injury or osteoarthritis. The authors in their article provide an overview of currently available medical and surgical therapeutic options. Medical therapy aims to preserve articular function for as long as possible and to delay surgical intervention. Further to the primarily pain-relieving symptomatic medication, causal treatment with glucosamine and chondroitin aims to improve the joint itself. However, no medical drugs are currently available that can slow down or reverse the process of cartilage degeneration. Surgical measures aim to trigger formation of repair tissue or partially relieve the weight placed on the joint. These procedures include debridement of cartilaginous fragments, marrow-stimulating techniques, transplantation of cartilaginous cells or stem cells, and weight relief by means of osteotomy.
Study identifies risk factors for complications after spine surgery
A study has identified several risk factors for a variety of complications and death shortly after spine surgery among men and women across the U.S. In the last 20 years, due to diagnostic and surgical advances, more and more patients have become appropriate candidates for spine surgery, and the number of these procedures performed has risen significantly. While medical experts acknowledge the potential benefits of spine surgery, they also understand that complications can reduce the success in the short and long term.
 “Complications following spine surgery may have a substantial impact on the quality of life of patients as well as the outcome of the primary surgical procedure,” said orthopaedic surgeon Andrew J. Schoenfeld, MD, one of the authors of a new study recently published in the Journal of Bone and Joint Surgery (JBJS). Relatively few studies have explored the impact of factors such as comorbid medical conditions (simultaneously and usually independently existing health problems, including diabetes and cardiovascular conditions), age, body mass index (BMI), and gender on the risk of complications following spine surgery. Most research to date has focused exclusively on wound infection, and few studies have explored other possible complications and death.
“At the present time, the results of this study may represent some of the best available evidence regarding risk factors for complications and mortality following spine surgery,” said Dr. Schoenfeld.
The study authors evaluated the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for the years 2005 to 2008. This database documents preoperative information and postoperative complications and death among patients receiving surgery at participating medical facilities across the United States.
“One of the principle advantages of the NSQIP dataset is that it encompasses patients in selected hospitals from across the United States and includes a variety of spine surgical procedures,” said Dr. Schoenfeld.
The study authors identified patients who received one or more spine operations.
- From 2005 to 2008, 3,475 spine-surgery patients were registered in the database.
- They ranged in age from 16 to 90, and the average age was 55.5.
- Fifty-four percent of the patients were men, and 76 percent were Caucasian.
- These patients underwent back surgery for conditions such as:
- Disc herniation (ruptured or slipped discs, the rubbery cushions between vertebrae);
- Spinal stenosis (narrowing of the spinal canal); and
- Degenerative disc disease (the progressive deterioration of discs).
Researchers then collected a wide range of demographic information and complications and death that occurred within 30 days after surgery for all the patients. Major complications included deep vein thrombosis (blood clots deep in the legs), sepsis (a life-threatening condition caused by a bacterial infection), deep wound infections, and unplanned return to the operating room. Minor complications included urinary tract infections, pneumonia, and superficial wound infections.
The death rate was .03 percent, (10 out of 3475 patients), while 7.6 percent (263 out of 3475 patients) experienced complications within 30 days after surgery. The preoperative and postoperative data indicated that increasing patient age and surgical wound problems independently increased the risk of death. The data also identified the following independent risk factors for developing one or more complications within this 30-day period:
- Older patient age;
- Congestive heart failure and/or a history of heart attack;
- Preoperative neurological problems;
- A history of spinal wound infection;
- Use of corticosteroids;
- A history of sepsis;
- A classification of 3 or higher according to the American Society of Anesthesiologists physical status classification system (a system that evaluates a patient’s health status prior to surgery); and
- Prolonged surgery times.
People who already have had spine surgery and those considering it should keep the results of this national study in perspective, said Dr. Schoenfeld. “Our study only documents complications and mortality that occurred within 30 days after surgery. Many studies exist that illustrate the safety and efficacy of spine surgery, and the intent of this work was not to be alarmist.”
URMC research could extend life of arthritic joints
A medication already approved to build bone mass in patients with osteoporosis also builds cartilage around joints and could potentially be repurposed to treat millions of people suffering from arthritis, according to orthopaedic research at the University of Rochester Medical Center.
The study authors hope their laboratory findings, published in the current issue of Science Translational Medicine, will set the stage for the first human clinical trials to test human parathyroid hormone (brand name: Forteo) in this growing patient population.
Since 2005, arthritis has been ranked as the leading cause of disability in the United States by the Centers for Disease Control and Prevention. And by 2030 an estimated 67 million people, or 25 percent of the adult population in this country will have osteoarthritis (OA), a painful, degenerative joint disease that often begins with an injury and results in the progressive loss of cartilage. Current treatments for OA do not help improve the cartilage in the diseased joint, they only make the pain more bearable. Examples include oral anti-inflammatory agents (such as Advil or Naproxen), narcotics, or steroid injections into the affected joint. Surgical replacement of the joint and cartilage is usually required, although this major intervention often carries its own set of complications.
“We believe that a potential alternative to this cycle of pain and reduced quality of life has gone unnoticed for the past decade,” said study co-author Michael J. Zuscik, Ph.D., associate professor, Department of Orthopedics & Rehabilitation, Center for Musculoskeletal Research at URMC. “Given that Forteo is already FDA approved, our experimental findings make a compelling case for further clinical study of this drug in the context of arthritis.”
The Food and Drug Administration approved Forteo a decade ago as a bone-building therapy for osteoporosis patients with severe bone loss. Although Zuscik and co-author Randy N. Rosier, M.D., Ph.D., professor of Orthopaedics & Rehabilitation, lead a laboratory that investigates osteoarthritis, through collaborative clinical work their group made an interesting observation: Occasionally, when a patient suffered from both disorders – osteoporosis and osteoarthritis – the symptoms of arthritis would improve after taking Forteo for osteoporosis.
This observation led the OA researchers to question whether the drug would have an impact on the molecular pathways that govern chondrocytes, the cells responsible for maintaining cartilage, and the changes that take place during joint degeneration. The team used a mouse model for post-traumatic knee osteoarthritis and demonstrated in several laboratory experiments that when Forteo was given daily for one month, the injured cartilage became as much as 32 percent thicker, cell production was enhanced, and genes and molecules associated with the degeneration of cartilage were suppressed.
The study was designed to mimic a common clinical situation in which injury to the meniscus and collateral ligaments result in the development of osteoarthritis later in life. Since the hallmark problem in osteoarthritis is the progressive and irreversible loss of cartilage, Zuscik said, the ability of parathyroid hormone to add new cartilage while blocking its degradation makes it a viable therapy.
In addition to the laboratory research, Zuscik and Rosier reviewed OA patient information from government databases. Of 4,000 people diagnosed with knee arthritis, they found 14 who were also taking Forteo for osteoporosis. This small group of people reported less arthritis pain and a higher ability to function than a matched population of patients who were not taking Forteo.
Although this data involved a very small number of people and is therefore not conclusive, Rosier said, it does confirm observations made by him and other URMC orthopaedic specialists.
Future studies are still needed to address several important questions. There is some concern, for instance, about the safety of Forteo, which is made by Eli Lilly and Company and carries a black-box warning because it has been found to cause an increased risk of the bone cancer osteosarcoma, in rats. Due to this potential long-term risk in humans, Forteo is prescribed for short-term use up to two years. Thus, researchers will need to determine how long the protective/regenerative effect on cartilage persists after treatment is stopped.
Hip fracture is associated with increased short-term death rates for some older women
Hip fracture is associated with an increase in short-term mortality (death within one year) for women ages 65 to 79 years and healthy women ages 80 years and older, although the risk returns to previous levels after one year for women ages 70 years and older, according to a report published by Archives of Internal Medicine, one of the JAMA/Archives journals.
“Such methodological limitations have made it difficult to determine whether the noted increase in mortality after hip fracture is the result of underlying poor health or the hip fracture itself,” according to the authors. Additionally, studies that explored the influence of age on mortality after hip fracture have conflicting results. The researchers sought to determine the short-term (one year or less), intermediate-term (between one and five years) and long-term (between five and 10 years) mortality associated with hip fracture, as well as whether healthy women ages 80 years and older would have increased mortality associated with hip fracture when compared with healthy controls of the same age.
Erin S. LeBlanc, M.D., M.P.H., from the Center for Health Research, Kaiser Permanente Northwest, Portland, Ore., and colleagues prospectively studied participants in the Study of Osteoporotic Fractures, a large community-based, multicenter study. Participants were recruited between 1986 and 1988 and followed until December 2005; the mean (average) follow-up was 14.4 years. The researchers selected 1,116 women with hip fracture and matched each with four control participants of the same age who did not have hip fracture (n = 4,464) for a total of 5,580 participants. Through a healthy older subset (n = 960) of participants ages 80 years or older who attended a 10-year follow-up examination and reported good or excellent health, the researchers were able to examine the association with health status. The authors determined incident (new-onset) hip fractures by examining radiology reports, and used death certificates to confirm participant deaths. For participants with hip fracture, the odds of death were twice as high in the year after the fracture as were controls (16.9 percent vs. 8.4 percent). The odds of short-term mortality increased in participants ages 65 to 70 years (16.3 percent vs. 3.7 percent) and 70 to 79 years (16.5 percent vs. 8.9 percent); an increase was also observed in women ages 80 years or older with good or excellent health (15.1 percent vs. 7.2 percent). After one year following fracture, participants with fracture and controls had similar mortality, except those with fracture ages 65 to 70 years who continued to have an increase in mortality.
The authors noted that, because the risk of hip fracture increases with age, hip fractures may become an even larger public health issue as the population ages. According to the results of the study, an association exists between age, health status (in those ages 80 years and older), and short-term mortality after hip fracture.
“If our findings are replicated, they would suggest that research should focus on hip fracture prevention and interventions in these groups that could decrease mortality during that high-risk period,” they write. “Women who are 65 to 70 years of age continue to have an increased risk of mortality for up to five to 10 years; therefore, prevention of hip fractures in these women should be of high priority.”
Back pain? Move, don't rest!
Move if you have back pain, this is the advice of a researcher at the Sahlgrenska Academy, University of Gothenburg. Patients with acute low back pain who were advised to stay active despite the pain fared better than those who were told to adjust their activity in line with their pain.
 The thesis looked at 109 patients with acute severe low back pain. They were randomly advised in one of two ways: “stay active even though it hurts” or “adjust your activity to the pain”.
They were also asked to keep a diary for seven days and to note how many steps they took each day, to what extent they could carry out their day-to-day activities and how they felt physically. They also completed a form to show whether they felt depressed or not.
In spite of having more pain, the group that was advised to be as active as possible recovered more quickly and did not feel depressed at the end of the follow-up.
“The other category, who had been advised from the very start to adjust their activity to their pain, were less mobile and felt slightly depressed compared to the patients who were active,” says Olaya-Contreras, a researcher at the Sahlgrenska Academy’s Department of Orthopaedics.
She believes that this could be because some people who are depressed and in pain experience the pain more acutely. Another explanation could be that the more acute the pain is perceived to be, the less a person wants or is able to move. This, according to Olaya-Contreras, is in line with previous research.
“I think that if you’re suffering with acute low back pain you should try to remain as active as possible and go about your daily business as well as you can. If you don’t keep moving, it’s easy to get locked into a downward spiral, as inactivity combined with pain can, in a worst case scenario, turn into long-term disability and an inability to work that, in turn, can lead to depressed mood and more pain.”
Olaya-Contreras therefore feels that the health service should introduce a routine investigation to determine the underlying psycho-social causes of patients’ back problems. This could measure the degree of perceived depression as well as anxiety and fear of movement.
“The results of the investigation and associated discussion could lead to patients taking a more active role and taking responsibility for their treatment,” says Olaya-Contreras. “I also believe that it can help patients to focus more on the positive resources they themselves have to handle the pain and master various physical movements even though it hurts.”
BOA/IOC 2011 Congress a success
September 13th-16th saw the combined meeting of the British Orthopaedic Association (BOA) and the Irish Orthopaedic Association (IOC) take place in the vibrant city of Dublin, the first time since 1998. Thousands of delegates flocked to the event held at the striking Convention Centre overlooking the River Liffey.
Senior orthopaedic experts held lectures and seminars at the event, with a main focus on Training, Education and Revalidation. BOA organisers felt the need to single-put these topics mostly due to the incoming proposed legislation by the GMC and DoH to re-introduce Revalidation from late next year.
In addition, attendees partook in various educational sessions, including Hot Topic debates, Workshops and Free Paper sessions, as well as the chance to look into the latest news and posters from Europe’s leading Orthopaedic researchers.
This year’s congress also featured a strong industry support, with many orthopaedic companies, organisations and charities impressing with their stands and highlighting their products and services to delegates.
Hosting alongside a busy three-day schedule of educational events, the BOA/IOC also ran a varied social programme, including a very successful opening evening drinks reception sponsored by OPN. Next year’s meeting will be held in Manchester on September 11th-14th.
New clinical treatment guideline outlines recommendations to reduce blood clots after hip and knee replacement
An updated clinical practice guideline released recently by the American Academy of Orthopaedic Surgeons (AAOS) Board of Directors recommends how to reduce the likelihood of blood clots after hip or knee replacement surgery, procedures that more than 800,000 Americans undergo each year.
The new guideline suggests use of preventive treatments and advises against routinely screening patients after surgery using ultrasound imaging.
“Hip and knee arthroplasty (joint replacement surgery) is among the most successful of procedures in terms of restoring function and minimising pain.
However, one possible complication that orthopaedic surgeons are concerned about is venous thromboembolic disease,” said Joshua Jacobs, MD, Academy second vice president, an orthopaedic surgeon at Rush University Medical Center in Chicago, who was chairman of the workgroup that developed the guideline.
Thromboembolic disease encompasses two conditions: deep vein thrombosis (DVT), or formation of a blood clot in a deep vein such as in the thigh or calf, and pulmonary embolism (PE). In the relatively uncommon event of a PE, pieces of a clot break free and travel through the vein to the lung, where they can lodge in an artery. PE typically causes no symptoms, however possible symptoms include shortness of breath, chest pain, light headedness or chest congestion. In very rare cases, PE can be fatal.
Likewise, in many patients, DVT causes no symptoms. However, in some patients, DVT can lead to symptoms such as leg swelling and pain that can necessitate further treatment or rehospitalisation. The goal of the orthopaedic surgeon is to prevent, as much as possible, the occurrence of PE and DVT following total hip and knee replacement.
According to the guideline, in the absence of prophylaxis, DVT occurs in about 37 percent of patients, as detected by imaging. The majority of those patients will remain asymptomatic and will require no further treatment. Recent studies in Denmark show that only 0.7 percent of hip replacement patients and 0.9 percent of knee replacement patients require hospitalisation because of DVT in the first three months after surgery.
“After looking at all available scientific research evidence, in a rigorous fashion to minimise bias, we made recommendations that can help guide practitioners in the safest and most effective ways to prevent this potentially serious complication,” said Jacobs.
Among the preventive measures the experts analysed for safety and effectiveness are mechanical compression devices, designed to improve blood flow in the legs after surgery, as well as drug therapy. Drug therapy involves anticoagulants, commonly called blood thinners, as well as aspirin, which interferes with blood clotting by acting on platelets.
The work group also outlined suggestions for future research to fill in the evidence gaps that were apparent through an exhaustive and systematic review of the medical literature. Further research is deemed critical to develop the optimum strategies to prevent venous thromboembolic disease in the safest and most effective manner.
From the evidence reviewed, the workgroup made the following recommendations for physicians treating patients before hip or knee replacement:
- Patients should stop taking antiplatelet medications (a type of anticoagulant), such as aspirin and clopidogrel (Plavix), because of the increased risk of blood loss during surgery with these drugs.
- A patient should discuss the timing of stopping any medication with his or her physician.
- A prior DVT or PE is an additional risk factor for thromboembolic disease and it is important that patients discuss any such event with his or her surgeon. There is insufficient evidence to recommend for or against routinely assessing patients for other possible risk factors.
- Patients may want to have the surgery performed under regional anesthesia, such as epidural or spinal, rather than general anesthesia. Although evidence suggests that these regional approaches do not affect the occurrence of DVT or PE, they do limit blood loss.
The workgroup also made these recommendations for care after hip or knee replacement:
- Hip and knee replacement patients should not have routine postoperative screening for thromboembolic disease with duplex ultrasonography (an ultrasound test that shows how blood moves through the arteries and veins). Screening with this test does not significantly reduce the rate of symptomatic DVT or PE or the rate of fatal PE.
- Patients should receive anticoagulant therapy (unless they have a medical reason for not being able to use these drugs, such as a bleeding disorder or active liver disease) and/or mechanical compression devices after a hip or knee replacement surgery. There is, however, insufficient evidence to recommend any particular preventive strategy or the duration of these treatments. Patients should discuss the duration and type of preventive treatment with their physician.
- After hip or knee replacement, patients should get up and walk as soon as safely possible. Although there is insufficient evidence that “early mobilisation” reduces DVT rates, early mobilisation is low cost, of minimal risk and consistent with current practice.
The full guideline, “Preventing Venous Thromboembolic Disease in Patients Undergoing Elective Hip and Knee Arthroplasty,” along with all supporting documentation and workgroup disclosures, is available on the AAOS website: www.aaos.org/guidelines.
Herbal supplements may cause dangerous drug interactions in orthopaedic surgery patients
Complementary and alternative medical (CAM) treatments can have serious and potentially harmful side effects when combined with medications prescribed during and after surgery, according to a review article in the Journal of the American Academy of Orthopaedic Surgeons (JAAOS).
About 20 percent of prescription users also take an herbal supplement, and those rates are higher — studies suggest between 35 and 70 percent — among orthopaedic patients who are candidates for surgery.
“Herbal remedies are classified as dietary supplements, meaning they are exempt from the safety and efficacy regulations that the U.S. Food and Drug Administration (FDA) requires for prescription and over-the-counter medications,” said David T. Rispler, MD, director of the Grand Rapids/Michigan State University Orthopedic Residency Program. “As a result, individual herbal remedies have not been thoroughly evaluated in large clinical trials, and little information is available on the interactions between drugs and herbs.”
In addition, many herbal products are marketed as “natural” or “homeopathic,” which may lead consumers to assume the products are safe, even when taken with prescription medicines, Dr. Rispler noted. “Herbal supplements can have a negative impact on patients both before and following surgery, and may interact with conventional medicines used to manage chronic conditions.”
“Traditional physician-patient communications, like intake interviews, often do not include the subject of alternative medical products. As a result, patients may fail to report that they are using them and continue to take them along with any prescribed medicines and before surgery, thinking the herbal products pose no risk,” said Dr. Rispler.
Many of the most popular herbal supplements used today can have serious side effects when combined with prescription medicines. For example:
- Feverfew (used for migraine prevention), ginger, cranberry, St. John’s Wort and ginseng can interact with the anti-clotting drug warfarin;
- Feverfew, ginger, and gingko can interact with aspirin;
- Garlic can interfere with anti-clotting medications and the immunosuppressant drug cyclosporine (prevents transplant rejection);
- Valerian (used as a sedative) can intensify anesthetics; and
- St. John’s Wort can interact with immunosuppressive drugs and potentially lead to transplant rejection.
Herbal products marketed for osteoarthritis also can pose serious risks when combined with prescription medications. For example:
- Glucosamine, chondroitin and flavocoxid can affect clotting agents;
- Black cohosh can interact with the cancer drug tamoxifen; and
- Cat’s claw can interact with clotting agents, blood pressure medications and cyclosporine.
Most surgery-related side effects can be avoided by stopping the CAM product at least one to two weeks prior to surgery and during the postoperative period while prescription medications such as blood thinners or antibiotics are being used. The problem arises when physicians do not know that a patient is using a CAM product, Dr. Rispler said.
“One of the main reasons that patients do not disclose the use of a CAM product is that they may not believe it is important information to convey to the physician because they feel they are safe to use and all-natural,” he said. “Patients may also decide not to report CAM product use if they are worried their physician may be prejudiced against the supplement’s use, or believe their physician will not have an understanding of the supplement.”
Although the use of herbal medicines should be monitored by patients’ primary care physicians, Dr. Rispler said orthopaedic surgeons should have an understanding of the potential side effects of some of the most common CAM products used by their patients, and be able to guide them in suspending use prior to surgery. To help ensure physicians are aware of the products their patients may be using, Dr. Rispler also recommends including CAM product-use questions on health/medical assessment forms to encourage patient disclosure.
“To help avoid potential side effects, orthopaedists should develop questionnaires that can be used prior to surgery to help determine if their patients are using CAM products.”
Drug prevents bone loss side effects of breast cancer medication
A new study has found that an osteoporosis drug protects against the bone damaging side effects of certain breast cancer medications. Published early online in Cancer, a peer-reviewed journal of the American Cancer Society, the study indicates that some breast cancer patients could take zoledronic acid in addition to their anti-cancer medications to maintain bone health.
Drugs called aromatase inhibitors stop the production of estrogen in postmenopausal women and therefore make less estrogen available to stimulate the growth of certain breast cancer cells. Many postmenopausal women with breast cancer are routinely treated for several years with these potentially life-saving drugs, but the agents can cause bone loss and fractures.
Adam Brufsky, MD, PhD, of the University of Pittsburgh Cancer Institute, and his colleagues conducted a study to see if the bone drug zoledronic acid could prevent and treat bone loss in postmenopausal breast cancer patients.
In their five-year study, called Z-FAST, 602 postmenopausal women with early breast cancer who were receiving the aromatase inhibitor letrozole were randomised to receive zoledronic acid simultaneously with letrozole or only after bone loss or fractures occurred.
The investigators observed significant and progressive increases in bone density throughout the five years of the study in women who initiated zoledronic acid at the start; in contrast, significant decreases in bone density occurred when zoledronic acid administration was delayed until bone loss was apparent. Over time, though, the rate of bone density decline in the delayed group slowed, most likely because more delayed patients received zoledronic acid by the end of the study. These findings indicate that bone density is maintained more effectively with upfront zoledronic acid, but bone loss is likely reversible so that initiating zoledronic acid, even after bone loss has developed, is beneficial.
“This study shows that bone loss from aromatase inhibitors can be prevented long term with a safe and effective drug that prevents osteoporosis,” said Dr. Brufsky. Zoledronic acid is currently approved by the U.S. Food and Drug Administration for conditions including osteoporosis and bone complications of cancer.
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