Stress fractures: concepts and therapeutics

Abstract

Most individuals who experience a stress fracture are young and healthy and do not appear to have an underlying metabolic bone disease. On the other hand, the presence of low bone mass and hormonal disturbances in some afflicted individuals might identify a cohort who needs endocrinological attention. Prospective, well-designed studies of stress fractures are needed to elucidate further underlying pathophysiological elements that predispose such individuals. Guidelines for prevention and treatment may follow from such well-controlled studies.

Bone Stress Injuries Are Associated With Differences in Bone Microarchitecture in Male Professional Soldiers

“…BSI is associated with a variety of biological, biomechanical, and environmental risk factors . Our results indicate differences in bone microstructure and vBMD assessed by HR‐pQCT in subjects with BSI at the tibial diaphysis.…”

“…However, the significantly increased levels of sclerostin and DKK‐1 in the case group—if permanently increased—may be interpreted as an osteocyte response to increased mechanical loading, leading to a decreased osteoanabolic effect and resulting in insufficient bone microstructure with ongoing age and eventually BSI. Sclerostin, which is chiefly produced by osteocytes, could serve as a reliable marker in assessing the risk for stress fractures in predestinated individuals, as altered sclerostin levels may impair bone remodeling and/or fracture healing . The predictive value of BTM at a timepoint close to trauma in this study should be interpreted with caution, as bone remodeling was clearly affected following injury.…”

“…The incidence of BSI is greatest among soldiers and military recruits, accounting 3.2–5.7 cases per 1,000 persons . Depending on the form and degree of physical activity, BSI is observed in multiple skeletal regions, but are most commonly reported in weight‐bearing sites, such as the tibial diaphysis, the fibula, or metatarsal bones . Because of its superior contrast resolution, non‐ionizing radiation as well as high sensitivity and specificity, magnetic resonance imaging (MRI) remains the modality of choice for the diagnosis of BSI …”

“…The underlying pathophysiology of BSI is multifactorial: Biological, biomechanical, and environmental risk factors, such as decreased bone mineral density (BMD), imbalanced bone remodeling, endocrinological changes, or a lower calcium intake in conjunction with vitamin D insufficiency are associated with the incidence of BSI . Nutritional behavior is also considered to contribute to bone structure and strength development in conferring greater mechanical resistance .…”

“…This multitude of underlying mechanisms partly explains the emergence of BSI in some individuals, yet not in others under similar circumstances …”