Keeping you up to date on recent headlines in orthopedic healthcare:
Data confirms improved outcomes for women with osteoporosis who are adherent to therapy . . . . Data released by CVS Caremark (Woonsocket, Rhode Island) indicates that 87% of women 18 years and older with osteoporosis, who were taking a drug therapy to treat the disease, did not experience a fracture during the two-year study period. The CVS Caremark data also found that those women with osteoporosis between the ages of 18-64 who were not on therapy were 5.7 times more likely to experience a fracture. "Osteoporosis impacts millions of women in the United States and the resulting fractures due to bone loss associated with the disease can have a significant impact on the individual's quality of life and increase overall healthcare costs for the patient and the payor," said Troyen Brennan, MD, Chief Medical Officer, CVS Caremark. "Our research suggests that the medications available today to treat osteoporosis are effective in combating the disease and those women who take and remain adherent to therapy are better able to maintain their mobility and quality of life while avoiding costly fractures." The study analyzed women diagnosed with osteoporosis over a two-year period. Untreated women less than 65 years of age were 5.7 times more likely to experience a fracture than those treated with a bisphosphonate, estrogen, or other hormone-related osteoporosis therapy. This study evaluated aggregated and de-identified data for almost 400,000 women from the CVS Caremark Health Management Claims Database who had incurred claims between 01/01/07 and 12/31/08.
New tissue scaffold regrows cartilage and bone . . . . MIT engineers and colleagues have built a new tissue scaffold that can stimulate bone and cartilage growth when transplanted into the knees and other joints. The scaffold could offer a potential new treatment for sports injuries and other cartilage damage, such as arthritis, says Lorna Gibson, the Matoula S. Salapatas Professor of Materials Science and Engineering and co-leader of the research team with Professor William Bonfield of Cambridge University (Cambridge, UK). "If someone had a damaged region in the cartilage, you could remove the cartilage and the bone below it and put our scaffold in the hole," said Gibson. The researchers describe their scaffold in a recent series of articles in the Journal of Biomedical Materials Research. The technology has been licensed to Orthomimetics (Cambridge, UK), a company launched by one of Gibson's collaborators, Andrew Lynn of Cambridge University. The company recently started clinical trials in Europe. The scaffold has two layers, one that mimics bone and one that mimics cartilage. When implanted into a joint, the scaffold can stimulate mesenchymal stem cells in the bone marrow to produce new bone and cartilage. The technology is currently limited to small defects, using scaffolds roughly 8 mm in diameter. The researchers demonstrated the scaffold's effectiveness in a 16-week study involving goats. In that study, the scaffold successfully stimulated bone and cartilage growth after being implanted in the goats' knees. There are currently a few different ways to treat cartilage injuries, including stimulating the bone marrow to release stem cells by drilling a hole through the cartilage into the bone; transplanting cartilage and the underlying bone from another, less highly loaded part of the joint; or removing cartilage cells from the body, stimulating them to grow in the lab and re-implanting them. The new scaffold could offer a more effective, less expensive, easier and less painful substitute for those therapies, said Gibson. The research was funded by the Cambridge-MIT Institute, the Whitaker-MIT Health Science Fund, Universities UK, Cambridge Commonwealth Trust and St. John's College Cambridge.
Placement of dental implants results in minimal bone loss . . . . Dental implants are frequently used as a replacement for missing teeth in order to restore the patient's tooth function and appearance. Previous research demonstrates that the placement of a dental implant disrupts the host tissue in the area of the implant, so practitioners often focus their treatment planning to carefully maintain the patient's bone and gum tissue surrounding the implant. A recent study published in the Journal of Periodontology found that the majority of bone remodeling occurred in the time between the implant placement and final prosthesis placement. Subsequently, little mean bone change was observed in the five years following the implant placement, independent of type of restoration or implant length. The study, conducted at the University of Texas Health Science Center at San Antonio, evaluated 596 dental implants placed in 192 patients over the age of 18. Patients were screened for adequate oral hygiene and bone volume. Exclusion criteria included heavy smoking, chewing tobacco use, drug abuse, and untreated periodontal disease, amongst others. Study author Dr. David Cochran, DDS, PhD, Chair of the Department of Periodontics at the University of Texas Health Science Center at San Antonio, and president of the American Academy of Periodontology (Chicago), believes that this study provides additional support for the use of dental implants to replace missing teeth. "As a periodontist, I am committed to saving my patients' natural dentition whenever possible. However, the results of this study help further indicate that a dental implant is an effective and dependable tooth replacement option. Since the patient's host tissue surrounding the dental implant largely remains unchanged in the five years following placement, the dental team can now focus on periodic assessment and treatment of other areas in the mouth as needed, and know that the implant is doing its job as a viable substitute solution."
NIST issues first reference material for tissue engineering . . . . The National Institute of Standards and Technology (NIST) last week issued its first reference materials to support the new and growing field of tissue engineering for medicine. The new NIST materials are samples of a typical tissue scaffold material that have been measured and documented by NIST for three different degrees of porosity. Three-dimensional tissue scaffolds, under development for some years, are biodegradable materials that are meant to be implanted in the body to provide a structurally sound framework for the patient's cells to implant and grow, in time repairing damaged tissue. The scaffolds are meant to be absorbed gradually by the body and replaced by normal tissue. Today they are used most commonly to help repair damaged bone, but other applications being studied. In addition to biocompatibility and biodegradability, successful 3-D tissue scaffolds have a number of physical requirements. Porosity or pore size is one key factor. The pores in the scaffold must be large enough to permit cells to infuse the structure and receive nutrients, but healthy cell growth also depends on the cell's immediate surroundings. If the pores are too large or spaced too far apart, cells will be unable to build the proper connections. The three new NIST reference materials are disks about 20 millimeters across and 5 millimeters high formed of crisscrossed layers polyester struts approximately 200 micrometers in diameter. Varying the spacing of the struts in each layer resulted in three different average porosities for the disks: 47% (average strut spacing of 200 micrometers), 60% (300 micrometers), and 69% (450 micrometers). These span the common range of pore sizes typically required for tissue engineering applications. The biodegradable polymer, polycaprolactone, originally was used for sutures, and was chosen for being relatively strong and stable when not exposed to water or sunlight. The material has been approved by the Food and Drug Administration for use in tissue engineering implants, but the NIST reference materials are not meant for use in the body. The release of these reference materials culminates a multi-year effort involving input from the FDA, the National Institutes of Health and ASTM Working Group WK6507 "Reference Scaffolds for Tissue Engineering."
— Compiled by Holland Johnson, MDD