Lower extremity insufficiency fractures: an underappreciated manifestation of endogenous Cushing's syndrome

Unveiling the hidden impact: Subclinical hypercortisolism and its subtle influence on bone health

In recent years, advancements in imaging technologies have led to an increased detection rate of adrenal incidentalomas (AI), with age demonstrating a significant correlation with their incidence. Among the various forms of functional adrenal incidentalomas, subclinical hypercortisolism (SH) stands out as a predominant subtype. Despite the absence of typical symptoms associated with Cushing's syndrome, both domestic and international research consistently establishes a robust link between SH and diverse metabolic irregularities, including hypertension, lipid metabolism disorders, glucose metabolism abnormalities, and disruptions in bone metabolism. Individuals with SH face an elevated risk of cardiovascular events and mortality, highlighting the clinical significance of addressing this condition. Prolonged exposure to elevated cortisol levels poses a significant threat to bone health, contributing to bone loss, alterations in bone microstructure, and an increased susceptibility to fractures. However, comprehensive reviews addressing bone metabolism changes and associated mechanisms in SH patients are currently lacking. Furthermore, the profound impact of concurrent SH on the overall health of the elderly cannot be overstated. A comprehensive understanding of the skeletal health status in elderly individuals with concomitant SH is imperative. This article aims to fill this gap by offering a detailed review of bone metabolism changes and associated mechanisms in SH patients arising from AI. Additionally, it provides a forward-looking perspective on research concerning skeletal health in elderly individuals with concurrent SH.

Recognition of Nonneoplastic Hypercortisolism in the Evaluation of Patients With Cushing Syndrome

The evaluation of suspected hypercortisolism is one of the most challenging problems in medicine. The signs and symptoms described by Dr Harvey Cushing are common and often create diagnostic confusion to even experienced endocrinologists. Cushing syndrome is classically defined as neoplastic hypercortisolism resulting from an ACTH-secreting tumor or from autonomous secretion of excess cortisol associated with benign or malignant adrenal neoplasia. The increasing recognition of the negative cardiometabolic effects of mild cortisol excess without overt physical signs of Cushing syndrome has led to more screening for endogenous hypercortisolism in patients with adrenal nodular disease, osteoporosis, and the metabolic syndrome. However, sustained or intermittent activation of the dynamic hypothalamic-pituitary-adrenal axis caused by chemical (alcohol), inflammatory (chronic kidney disease), psychologic (major depression), and physical (starvation/chronic intense exercise) stimuli can result in clinical and/or biochemical features indistinguishable from neoplastic hypercortisolism. Nonneoplastic hypercortisolism (formerly known as pseudo-Cushing syndrome) has been recognized for more than 50 years and often causes diagnostic uncertainty. This expert consultation describes two patients with features of Cushing syndrome who were referred for inferior petrosal sinus sampling for the differential diagnosis of ACTH-dependent hypercortisolism. Both patients were discovered to have nonneoplastic hypercortisolism: one from a covert alcohol use disorder and the other to chronic kidney disease. This consultation emphasizes the value of a good history and physical examination, appropriate laboratory testing, and the desmopressin acetate stimulation test to aid in distinguishing neoplastic from nonneoplastic hypercortisolism.

Recurrent Metatarsal Fractures in a Patient With Cushing Disease: A Case Report

Cushing syndrome (CS) can result from excess exposure to exogenous or endogenous glucocorticoids. The most common endogenous cause of CS is an adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma, known as Cushing disease (CD). Patients typically present with characteristics including truncal obesity, moon facies, facial plethora, proximal muscle weakness, easy bruising, and striae. Insufficiency fractures of the metatarsals are a rare presentation for CS. A 39-year-old premenopausal woman presented to the orthopedic outpatient clinic with recurrent metatarsal fractures and no history of trauma. A metabolic bone disease was suspected, and after further evaluation by endocrinology services, the CD was diagnosed. Surgical resection was performed, and pathology confirmed the presence of a pituitary adenoma. Multiple, recurrent, non-traumatic metatarsal fractures can be the initial presentation of CD in a premenopausal woman.

Bone stress injuries

Bone stress injuries, including stress fractures, are overuse injuries that lead to substantial morbidity in active individuals. These injuries occur when excessive repetitive loads are introduced to a generally normal skeleton. Although the precise mechanisms for bone stress injuries are not completely understood, the prevailing theory is that an imbalance in bone metabolism favours microdamage accumulation over its removal and replacement with new bone via targeted remodelling. Diagnosis is achieved by a combination of patient history and physical examination, with imaging used for confirmation. Management of bone stress injuries is guided by their location and consequent risk of healing complications. Bone stress injuries at low-risk sites typically heal with activity modification followed by progressive loading and return to activity. Additional treatment approaches include non-weight-bearing immobilization, medications or surgery, but these approaches are usually limited to managing bone stress injuries that occur at high-risk sites. A comprehensive strategy that integrates anatomical, biomechanical and biological risk factors has the potential to improve the understanding of these injuries and aid in their prevention and management.

Stress fracture of proximal tibia after proximal fibula osteotomy: A case report

Introduction

Proximal fibula osteotomy (PFO) is a new method for treating medial compartment osteoarthritis of the knee, which is based on the theory of differential settlement (nonuniform settlement). This procedure has been widely recognized for its advantages of relative simplicity, low rate of postoperative complications, and low postoperative costs. Stress fracture of the proximal tibia after PFO has not been previously reported.

Case presentation

We report a 62-year-old woman with chronic rheumatoid arthritis (RA) underwent left PFO for chronic knee pain, who developed a stress fracture of the proximal tibia more than 1 year after PFO.

Clinical discussion

In the early stage of proximal tibia stress fracture, due to the concealment of radiography manifestations, doctors from another hospital performed total knee arthroplasty (TKA) for the patient. They ignored the treatment of stress fracture of the proximal tibia, and the stress fracture was further aggravated after surgery. Six months later, the patient underwent open reduction and internal fixation with a plate and screw in the left proximal tibia fracture at our hospital. The patient was followed up at the hospital three months after open reduction, and the proximal tibia stress fracture began to heal.

Conclusion

RA is usually not confined to the medial compartment and its pathogenesis is different from that of osteoarthritis. Therefore, PFO is not an appropriate procedure for this type of patient.

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Stress fracture of proximal tibia after PFO has not been previously reported.

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This case is extremely rare of a stress fracture of the proximal tibia more than 1 year after PFO.

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RA is usually not confined to the medial compartment that PFO is not an appropriate procedure for this type of patient.

Hidden hypercortisolism: a too frequently neglected clinical condition

PURPOSE

Classic Cushing's syndrome (CS) is a severe disease characterized by central obesity, hypertension, easy bruising, striae rubrae, buffalo hump, proximal myopathy and hypertricosis. However, several CS cases have also been reported with unusual or camouflaged manifestations. In recent years, several authors investigated the prevalence of "hidden hypercortisolism" (HidHyCo) among subjects affected with bone fragility, hypertension and type 2 diabetes mellitus (DM2). The prevalence of the HidHyCo is estimated to be much higher than that of classic CS. However, similarly to classic CS, HidHyCo is known to increase the risk of fractures, cardiovascular disease and mortality.

METHODS

We reviewed all published cases of unusual presentations of hypercortisolism and studies specifically assessing the HidHyCo prevalence in diabetic, osteoporotic and hypertensive patients.

RESULTS

We found 49 HidHyCo cases, in whom bone fragility, hypertension and diabetes were the presenting manifestations of an otherwise silent hypercortisolism. Amongst these cases, 34.7%, 32.7%, 6.1% and 19.0%, respectively, had bone fragility, hypertension, DM2 or hypertension plus DM2 as the sole clinical manifestations of HidHyCo. Overall, 25% of HidHyCo cases were of pituitary origin, and bone fragility was the very prevalent first manifestation among them. In population studies, it is possible to estimate that 1-4% of patients with apparent primary osteoporosis has a HidHyCo and the prevalence of this condition among diabetics ranges between 3.4 and 10%.

CONCLUSION

These data indicate that patients with resistant or suddenly worsening hypertension or DM2 or unexplainable bone fragility should be screened for HidHyCo using the most recently approved sensitive cut-offs.