The Effect of Abnormal Vitamin D Levels in Athletes.

Vitamin D is a lipophilic prohormone integral to musculoskeletal, autoimmune, oncologic, cardiovascular, and mental health. Of particular importance to the orthopedic surgeon is the role of vitamin D in the regulation of bone mass, muscle strength, and physical performance. Although vitamin D-related skeletal pathologies are rare in industrialized nations, emerging research in the field has shown that most American adults have inadequate levels of vitamin D. Even among athletes, there is a high prevalence of vitamin D deficiency, which may place competitors at risk of stress fractures, illness, and delayed muscle recovery. Adequately identifying vitamin D-deficient individuals in need of supplementation is important to help optimize performance and prevent future injury. The goal of this review is to describe the epidemiology of vitamin D deficiency and its effects on athletic performance and musculoskeletal health. Future double-blinded studies of vitamin D supplementation in athletes are needed. We recommend treating athletes who have insufficient or deficient vitamin D levels

Critical appraisal of the role of glucosamine and chondroitin in the management of osteoarthritis of the knee

Steven J Narvy1, C Thomas Vangsness Jr21Keck School of Medicine, University of Southern California, Los Angeles, CA, USA; 2Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, USAAbstract: Osteoarthritis (OA) is the most common musculoskeletal disease in the United States, with rising prevalence. Medical management of OA involves acetaminophen, nonsteroidal anti-inflammatory drugs, and other analgesics, all of which are of variable efficacy and are associated with significant side effects and toxicities. The purpose of this review is to critically evaluate the efficacy of glucosamine and chondroitin, both as single agents and in combination, for the treatment of knee OA. Also evaluated were the level of evidence and funding support of the included articles. Almost every included trial of glucosamine sulfate, glucosamine hydrochloride, and chondroitin sulfate has found the safety of these compounds to be equal to that of placebo, though their therapeutic efficacy in decreasing knee OA pain and improving joint function is variable. Additionally, there are data to support a role of these agents in reducing radiographic progression of knee OA. Industry involvement, however, remains prominent. Further, more comprehensive study by independent researchers free of industry ties is necessary to identify a subset of patients in whom the use of glucosamine and/or chondroitin would be most beneficial. These agents may be safely tried as an initial therapy in select OA patients prior to initiating therapy with nonsteroidal anti-inflammatory drugs, acetaminophen, and other traditional medications.Keywords: glucosamine sulfate, glucosamine hydrochloride, chondroitin sulfate, knee osteoarthritis, nutritional supplement, nutraceutica

The Effect of Abnormal Vitamin D Levels in Athletes.

Vitamin D is a lipophilic prohormone integral to musculoskeletal, autoimmune, oncologic, cardiovascular, and mental health. Of particular importance to the orthopedic surgeon is the role of vitamin D in the regulation of bone mass, muscle strength, and physical performance. Although vitamin D-related skeletal pathologies are rare in industrialized nations, emerging research in the field has shown that most American adults have inadequate levels of vitamin D. Even among athletes, there is a high prevalence of vitamin D deficiency, which may place competitors at risk of stress fractures, illness, and delayed muscle recovery. Adequately identifying vitamin D-deficient individuals in need of supplementation is important to help optimize performance and prevent future injury. The goal of this review is to describe the epidemiology of vitamin D deficiency and its effects on athletic performance and musculoskeletal health. Future double-blinded studies of vitamin D supplementation in athletes are needed. We recommend treating athletes who have insufficient or deficient vitamin D levels