Hip, Osteoporosis: New Paradigm

Fractures of the thoracolumbar spine in osteoporosis

Due to increasing life expectancy, the prevalence of fractures caused by osteoporosis is raising. These fractures significantly reduce the quality of life in the elderly population. They represent both a disease and an injury simultaneously. While they were once treated solely with conservative methods, new techniques and implants are expanding the indications for surgical treatment. This article presents the current treatment options.

ESTES recommendations on proximal humerus fractures in the elderly

PURPOSE

The section for the skeletal trauma and sport's injuries of the European Society for Trauma and Emergency Surgery (ESTES) appointed a task force group to reach a consensus among European countries on proximal humeral fractures.

MATERIAL/METHODS

The task force group organized several consensus meetings until a paper with final recommendations was confirmed during the ESTES Executive Board meeting in Berlin on 25 October 2018.

CONCLUSION

The Recommendations compare conservative and four possible operative treatment options (ORIF, nailing, hemi- and total reverse arthroplasty) and enable the smallest common denominator for the surgical treatment among ESTES members.

Surgical Management of Atypical Femur Fractures Associated With Bisphosphonate Therapy

Atypical femur fractures associated with long-term bisphosphonate use can be challenging injuries to manage. Not only do they have a prolonged healing time and increased rate of nonunion as compared to typical femur fractures, intraoperative complications are not infrequent and can be catastrophic. Given the pathologic nature of these fractures, a multidisciplinary approach to the patient's care is necessary. Treatment begins with medical optimization and careful surgical planning. Radiographic characteristics of the fracture and femoral osteology dictate reduction strategy, adjunctive surgical techniques, and implant choice. Intraoperative complications including malreduction, iatrogenic fracture, and fracture propagation can be avoided with thoughtful planning. The purpose of this article is to discuss the technical aspects of surgical management of atypical femur fractures. We also discuss management of intraoperative complications and treatment failure. Finally, we provide an update on recommendations for postoperative medical treatment and management of the contralateral femur.

Atypical femoral fractures

Bisphosphonates (BPs) represent the most widely used therapy for osteoporosis. Recently, a relationship between long-term treatment with BPs and a subset of atypical femoral fractures (AFFs) from below the lesser trochanter to the sovracondilar line has been described. Many etiopathogenetic theories have been invoked to explain AFFs: reduced bone turnover and increased osteoblast bone apposition with accumulation of microdamage and decreased bone toughness with subsequent increased risk of micro-cracks and duration fractures, collagen fiber cross-linking and vascularization impairment. Based on published studies, a task force of the American Society for Bone and Mineral Research has redacted the diagnostic criteria of AFFs by classifying them according to their major and minor criteria. The treatment for displaced AFFs is osteosynthesis, but there is a lack of evidence for undisplaced AFFs and the duration of fracture treatment. BPs have a proven efficacy in osteoporotic fracture reduction as well as in the treatment of other bone diseases caused by the downregulation of osteoclast activity. BPs have an excellent benefit-to-risk ratio; however, minor adverse events, such as AFFs, occur in a variable percentage of patients treated over a long period of time.

Osteoporosis update

INTRODUCTION

Osteoporosis is a chronic disease that is estimated to affect more than 75 million people worldwide. The US Department of Health and Human Services projects that the disease will impact more than 10 million women by 2020 if efforts to prevent it are ineffective. This article provides an overview of the pathophysiology of osteoporosis, prevention measures, and an update of the US Food and Drug Administration-approved medications that are used in the treatment of this widespread disease.

METHODS

The current literature on the pathology, risks, and treatment of osteoporosis was reviewed. Studies providing the evidence for best practices are included in the following sections: prevention, diagnosis, and treatment of osteoporosis. Current national standards for diagnosis and treatment are highlighted.

RESULTS

Bisphosphonates continue to be the most popular and widely used pharmacologic treatment for osteoporosis. However, when bisphosphonates are contraindicated or cause side effects so serious that it is not possible for some women to use them, alternative pharmacologic treatments and forms of dosing are available.

DISCUSSION

When lifestyle and dietary modifications are insufficient to offset a diagnosis of osteoporosis, there are a variety of pharmaceutical options available that will provide safe and effective protection against fracture due to osteoporosis.

Development of 41Ca-based pharmacokinetic model for the study of bone remodelling in humans

BACKGROUND AND OBJECTIVE

Initial studies show that 41Ca may be employed as a useful diagnostic bioassay for monitoring metabolic bone disease and its treatment management. The 41Ca-based pharmacokinetic model is developed to assess its feasibility in monitoring bone disease and clinical responsiveness to therapeutic regimens.

METHODS

A four-compartment calcium kinetic model is developed to interpret the results of clinically measured 41Ca tracer kinetics for oral and intravenous dose. This model is extended to simulate changes in bone turnover due to osteoporosis by using Gompertzian function with and without cellular accommodation. The rate constants obtained by fitting to the experimental data on drug intervention are used to simulate the impact of strategic treatment intervention.

RESULTS

The present model fits well with the available experimental data on 41Ca tracer kinetics. In the simulated osteoporotic model, the negative bone balance (i.e. bone loss) reflected by 41Ca/Ca urine ratio is used to demonstrate slow/fast increase over time compared to the normal state. The cellular accommodation impact is reflected by a recovery from perturbed balance. The model's predictive ability on the impact of therapeutic intervention is verified using published experimental data. The effect of bisphosphonate intervention results in positive bone balance (i.e. bone gain).

CONCLUSION

The four-compartment 41Ca tracer kinetic model can be flexibly used in the interpretation of results obtained from ongoing clinical studies.