Osteoporosis and cement usage in total hip arthroplasty.

PURPOSE: Cement usage in total hip arthroplasty (THA) is increasingly common. However, osteoporosis-related fracture risk in cemented vs uncemented THA patients is poorly characterized. We aim to analyze the usage of metabolic bone care and osteoporosis fracture risk in cemented vs uncemented THA patients using FRAX and radiographic bone measurements. METHODS: Chart review on 250 THA patients was performed retrospectively. Demographics, FRAX scores, hip radiograph measurements, osteoporosis diagnosis, treatment and screening were compared between cemented and uncemented THA patients. Logistic regression model was used to analyze factors influencing cement usage. RESULTS: Cemented THA patients have significantly higher osteoporosis-related fracture risk as measured by FRAX major (20% vs 13%) and FRAX hip (8% vs 5%). There is no significant difference in osteoporosis treatment, vitamin D / calcium supplementation, or metabolic bone disease screening based on patients' cement status. Female sex and rheumatoid arthritis status significantly predict cement usage, but FRAX scores do not predict cement usage. Additionally, 50% (10/20) of patients with Dorr C classification were uncemented. CONCLUSION: Although some patients undergoing THA with high osteoporosis-related fracture risk were identified and cemented, some risk factors including poor proximal femur shape (by Dorr classification) and poor bone quality (as measured by FRAX score) were potentially overlooked. Cemented patients had an increased risk for fractures but did not receive appropriately increased osteoporosis screening or treatment. LEVEL OF EVIDENCE: III.

Rationale for Bone Health Optimization in Patients Undergoing Orthopaedic Surgery.

Osteoporosis is common, affecting more than 40 million people, and is associated with increased fracture risk, loss of independence, chronic pain, and disability. Osteoporosis is underdiagnosed and undertreated even after fracture where secondary fracture prevention has been shown to be cost effective in reducing further fracture risk and mortality. Osteoporosis is also undiagnosed in patients undergoing orthopaedic and spine surgery in up to one-third of cases and negatively affects outcomes, need for revision surgery, and risk of complications. The diagnosis of osteoporosis was previously based on bone mineral density; however, recent clinical definitions include T-scores less than -2.5, the presence of hip and spine fractures, and high fracture risk. Surgeons should adopt bone health optimization for elective surgery. This program screens patients to determine whether a bone mineral density test is indicated and provides counseling for nutritional supplements, elimination of toxins, fall risk assessment, and education regarding bone health. Following assessment, patients meeting the criteria for osteoporosis are referred to a bone health specialist or a fracture liaison program. Both antiresorptive and anabolic antiosteoporotic medications appear effective at improving outcomes and reducing complications of orthopaedic and spine surgery, although a delay in surgery may be required.

The Basics of Bone Physiology, Healing, and Osteoporosis.

Osteoporosis is a skeletal condition characterized by decreased bone mineral density and poor bone quality with resultant greater fracture risk. There has been a focus on bone mineral density deficiency, which is easily measured with dual-energy x-ray absorptiometry and managed with pharmaceutic medications. More recently, impaired bone quality independent of bone mineral density has been recognized as a potential cause of fragility fracture and poor bone healing. Many conditions lead to poor bone quality; the most common is vitamin D deficiency and others are genetic causes and other nutritional deficits. In addition, the cellular and molecular changes associated with osteoporosis are being investigated and are potential targets for treatment. Treatment of patients with poor bone health include nutritional supplementation with vitamin D and calcium, weight-bearing exercises, and antiosteoporotic medications when warranted. Antiosteoporotic medications include antiresorptive drugs such as diphosphonate and denosumab that inhibit osteoclastic bone resorption. Anabolic agents such as teriparatide, abaloparatide, and romosozumab stimulate osteoblastic differentiation and bone formation. All these agents are effective in reducing fracture risk.

Allogeneic mesenchymal progenitor cells for posterolateral lumbar spine fusion in sheep.

BACKGROUND CONTEXT: Osteoconductive porous ceramic bone graft materials supplemented with mesenchymal precursor cells (MPC) derived from autologous bone marrow aspirates have been shown to stimulate successful interbody and posterolateral spine fusion in preclinical models. Recent advances in immunomagnetic cell sorting have enabled purification and isolation of pluripotent stem cells from marrow aspirates and have expanded stem cell technology to allogeneic cell sources. Allogeneic MPC technology combined with appropriate synthetic biomaterial carriers could provide both the osteogenic and osteoconductive components needed for successful posterolateral spine fusion without the need for autologous bone harvest or expensive recombinant protein technology. PURPOSE: To determine the safety and efficacy of a hydroxyapatite:tricalcium phosphate graft material supplemented with allogeneic mesenchymal precursor cells in posterolateral lumbar spine fusion using an ovine model. STUDY DESIGN: Skeletally mature ewes underwent single-level instrumented posterolateral lumbar spine fusion using either autograft (AG), hydroxyapatite:tricalcium phosphate carrier (CP), or CP supplemented with allogeneic mesenchymal progenitor cells (MPCs). Three doses of MPCs were evaluated: 25 × 106 cells (low dose, LD), 75 × 106 cells (mid dose, MD), and 225 × 106 cell (high dose, HD). Animals survived for either 4 or 9 months. METHODS: Plain radiographs were acquired and scored for bridging bone at regular intervals during healing to monitor fusion development. Hematology, coagulation, and serum chemistry were monitored at regular intervals throughout the study to monitor animal health. After necropsy, computed tomography, high-resolution radiography, biomechanical testing, organ pathology, bone histopathology, and bone histomorphometry were conducted to monitor the safety and ascertain the efficacy of MPC treatment. RESULTS: MPC treatment in this spine fusion model resulted in no observed adverse systemic or local tissue responses. Radiographically, fusion scores for MPC-treated animals were uniformly higher compared with those treated with carrier alone (CP) after 3 months and continued the same trend throughout 9 month of healing. Quantitative computed tomography confirmed better connectivity of the fusion for MPC treatment groups compared with CP. Biomechanical analyses were not able to differentiate between treatment groups. Histomorphometry results confirmed radiographic and quantitative computed tomography results; cell-supplemented treatment groups and autograft had equivalent amounts of bone within the fusion mass and less bony fusion tissue was found within the fusion mass in specimens from the CP treatment group. No conclusive effects of cell dose of fusion efficacy were noted. CONCLUSIONS: Adult allogeneic mesenchymal precursor cells delivered via a hydroxyapatite:tricalcium phosphate carrier were both safe and efficacious in this ovine spine fusion model. Results from this preclinical study support that allogeneic mesenchymal precursor cells produced fusion efficacy similar to that achieved using iliac crest autograft, thereby providing a safe and viable option to achieve successful posterolateral spine fusion.

Atypical femoral fractures: a review of the literature.

Bisphosphonates are the most commonly used drugs worldwide for treating osteoporosis. Atypical femoral fractures most commonly are associated with prolonged bisphosphonate use. They also may occur with denosumab use or in patients without a history of using these drugs. In this article, we provide a comprehensive review of the mechanism of action of bisphosphonate and the definition, incidence, epidemiology, pathogenesis, diagnosis, management, and prevention of atypical femoral fractures.

Osteoporosis: management and treatment strategies for orthopaedic surgeons.

Osteoporosis is a metabolic condition that is gaining increasing attention as people live longer. It may frequently be present in patients with and without fracture. Nonpharmacologic methods and pharmacologic methods may be used to treat osteoporosis and related fractures. The ultimate goal in managing and treating osteoporosis is to optimize fracture risk reduction. Commonly used nonpharmacologic interventions include calcium and vitamin D supplementation, fall prevention, hip protectors, and balance and exercise programs. These interventions act in conjunction with pharmacologic methods, if prescribed.

Nonpharmacologic management of osteoporosis to minimize fracture risk.

The traditional management of osteoporosis has focused on the pharmacologic aspects of treatment. Nonpharmacologic approaches, such as the use of orthoses, exercise programs, calcium and vitamin D supplementation, fall prevention, and kyphoplasty have largely been overlooked. Evidence for an essential contribution of nonpharmacologic treatments in the management of osteoporotic patients is increasing, particularly for patients who cannot, or will not, comply with medication regimens. This Review highlights the most important aspects of nonpharmacologic management of osteoporosis.

How much calcium is in your drinking water? A survey of calcium concentrations in bottled and tap water and their significance for medical treatment and drug administration.

INTRODUCTION: Different forms of water vary in calcium content. High divalent ion (i.e., Ca(2+), Mg(2+), etc.) concentration is deleterious to the absorption and efficacy of the bisphosphonate group of drugs in osteoporosis treatment. Water with high calcium concentration may also present an alternate pathway of calcium administration. In either case, knowing the actual concentration is critical. HYPOTHESIS: The current paper is a surveillance study. We hypothesize that there is considerable variation in the calcium concentrations in the various water sources: tap water from US and Canadian cities of different regions and purified, spring, and mineral bottled waters. In addition, we hypothesize that the water filter removes a significant amount of minerals including calcium from the water. METHODOLOGY: Calcium concentrations in various city tap waters, as well as an assorted number of bottled waters, were determined through the direct inspection of scientific data. The effect of filtering was also determined by mineral analysis of mineral water directly before and after filtration. RESULT: The calcium concentration of water varies from 1 to 135 mg/L across the USA and Canada. Most spring waters were found to have a relatively low calcium concentration, with an average of 21.8 mg/L. Purified waters contain a negligible calcium concentration. Mineral waters, on the other hand, were generally found to contain higher calcium concentrations, an average of 208 mg/L of calcium. Filtration was found to remove a considerable amount of calcium from the water, removing 89% on average. CONCLUSION: Calcium concentration in water varied substantially from different sources in the USA and Canada. Bottled waters presented with concentrations of calcium covering a very large range. Certain tap and bottled waters present with concentrations of calcium sufficient to exhibit a deleterious effect on bisphosphonate treatment. Alternatively, certain waters may be used as a source of calcium that may provide over 40% of the recommended daily intake for calcium.

Osteoporosis and skeletal fractures.

Osteoporosis affects millions of individuals worldwide, rendering them susceptible to fragility fractures of the spine, hip, and wrist and leading to significant morbidity, mortality, and economic cost. Given the substantial impact of osteoporosis on both patients and the medical community, it is imperative that physicians improve awareness and knowledge of osteoporosis in the setting of low-energy fractures. In this review, we provide information on effective means of preventing fragility fractures and introduce clinicians to issues pertinent to the patient who suffers an osteoporotic fracture. Prevention of fragility fractures centers around adequate mineral nutrition, including daily calcium and vitamin D supplementation, as well as prescription antiresorptive medications such as bisphosphonates or teriparatide therapy in severe cases, both of which have been shown to decrease future fracture risk. Balance and strength training also play important roles in the management of the osteoporotic patient, particularly following a low-energy fracture, and external hip protectors may be useful for certain patients. Kyphoplasty and vertebroplasty are two minimally invasive techniques that show great promise in the treatment of vertebral compression fractures, although questions regarding long-term biomechanical effects still exist. Traditionally, osteoporosis has been underdiagnosed and undertreated following a low-energy fracture in an elderly patient. Although treatment rates may be improving through public health initiatives, the majority of patients with osteoporosis remain inadequately treated. Perioperative intervention programs that focus on patient education about osteoporosis and treatment options lead to significant increases in intervention and treatment. Reducing the risk of skeletal fractures in patients susceptible to osteoporosis involves improved physician education on the risk factors and management of osteoporosis, as well as informing patients on the significance of dual-energy X-ray absorptiometry testing and medical treatment so that they may serve as their own healthcare advocates in this often-undertreated disease.

Orthopedic management of vertebral and long bone fractures in patients with osteoporosis.

Because of the evolving demographics of the world's population, fracture surgeons must become experts in the treatment of fractures in osteoporotic bone. Toward this end, fracture surgeons are learning to modify the classic techniques of internal fixation to adapt them to the elderly population. Screws should be placed into the best quality of bone available, which, in most cases, is an opposing cortex. Screw fixation can be augmented using acrylic cement. When using plate fixation, stable bone contact at the fracture site is the most important factor in reducing strain in the plate. Shortening of the affected bone is advisable to achieve this contact in comminuted fractures. Plates should not be used to bridge areas of comminution in osteoporotic bone. Plates should generally be as long as is compatible with the affected bone, with screws placed as close to and as far away from the fracture site as possible. When confronted with diaphyseal fractures or fractures with metaphyseal-diaphyseal comminution, locked intramedullary nails can be used. Angled blade plates are applicable to osteoporotic metaphyseal fractures but should be used as tension band plates, which require stable load-sharing contact opposite the plate. Antiglide plating and use of tension band wires are also effective strategies for osteoporotic fractures. Finally, to reduce the morbidity of bone graft harvest and to ensure adequate volumes of graft, the use of bone graft substitutes is particularly applicable in elderly patients. All patients with evidence of osteoporosis should be started on a medical regimen to combat further bone loss that includes calcium supplementation with a prescription for antiresorptive agents, including bisphosphonates, calcitonin, or hormone replacement therapy.

Medical management of osteoporosis.

Osteoporosis is characterized by low-energy fractures resulting from inadequate bone mass and compromised microarchicture. Bone mass is maximized by adequate nutrition and calcium intake, normal menstrual cycles, and appropriate exercises. Low bone density, as determined by dual-energy x-ray absorptiometry, and high bone turnover, as characterized by elevated bone collagen breakdown products, are the primary indicators of bone fragility. Prevention and treatment of osteoporosis should emphasize adequate calcium and vitamin D intake and exercise. In addition, estrogen supplementation and selective estrogen receptor modulators (estrogen antagonists) can enhance bone mass and decrease the risk of spinal fractures, oral and intravenous bisphosphonates can significantly decrease the incidence of both spinal and hip fractures, and antiosteoporotic agents can help rebuild healthy bone.

Improvement in the undertreatment of osteoporosis following hip fracture.

BACKGROUND: Osteoporosis is a common disease characterized by decreased bone mass and increased fracture risk in postmenopausal women and the elderly. Hip fractures are among the most common consequences of osteoporosis and unfortunately usually occur late in the course of the disease. When a patient is admitted to the hospital with a fragility hip fracture, a unique opportunity for diagnosis and treatment presents itself. Fortunately, several medications have proven to be effective in lowering the risk of future fractures. The purposes of the present study were to test the hypothesis that most fragility hip fractures go untreated and to determine whether educational efforts to raise physician awareness have led to an improvement in osteoporosis treatment rates. METHODS: A retrospective cohort study was performed with use of the patient databases at two university medical centers and one university-affiliated community hospital. The charts of 300 randomly selected patients were sorted with use of ICD-9 (International Classification of Diseases, Ninth Revision) codes for femoral neck fractures. There were 100 patients from each center, with twenty-five patients from each year between 1997 and 2000. The admitting diagnosis, mechanism of injury, admission medications, procedures performed during hospitalization, and discharge medications were then extracted and analyzed. During this period, the National Osteoporosis Foundation established guiding principles for the treatment of fragility fractures. RESULTS: Of the seventy-five patients from all centers for each year from 1997 to 2000, 11%, 13%, 24%, and 29%, respectively, were discharged with a prescription for some medication targeting osteopenia, either supplemental calcium or an antiosteoporotic medication (estrogen, calcitonin, a bisphosphonate, or raloxifene). A trended chi-square analysis of this increase revealed a p value of <0.001, indicating that this improvement in treatment was unlikely due to chance alone. Fifty-eight (19.3%) of the 300 patients in the study received a prescription at the time of discharge. However, forty of these patients (13.3% of the overall group) received calcium and only eighteen (6.0% of the overall group) received a medication to actively prevent bone resorption and treat osteoporosis. In addition, no patient underwent a bone density scan while in the hospital. CONCLUSIONS: Elderly patients and postmenopausal women who are admitted to the hospital and diagnosed with a low-energy femoral neck fracture have been undertreated for osteoporosis. However, over the four years of the present study, there was a significant increase in the rate of treatment. It is hoped that treatment rates will continue to increase in the future with continued educational efforts.

Nonmedical management of osteoporosis.

Nonmedical therapies are playing an increasing role in the management of osteoporosis and its complications. They serve as useful adjuncts to medical treatment. Several areas of nonmedical options for the management of osteoporosis include bracing, exercise, and vertebroplasty and kyphoplasty.