Slipped Capital Femoral Epiphysis as a Presentation of Underlying Metabolic Disorders: Pseudohypoparathyroidism and Juvenile Hypothyroidism

Abstract

Slipped capital femoral epiphysis (SCFE) is an abnormality of the proximal femoral physis typically occurring in adolescents and most commonly associated with obesity, although its exact etiology is unknown. In addition to obesity, other associations and predisposing factors proposed in the literature include trauma, vascular injury or compromise, and immunologic, genetic, and metabolic conditions. While not common, metabolic conditions are known to predispose to SCFE and it is essential for radiologists to recognize SCFE as a possible initial presentation of an underlying metabolic disorder. Understanding imaging findings and identification of atypical presentations of SCFE by radiologists can assist clinicians in guiding workup and lead to expedited treatment to prevent worsening outcomes associated with developmental delay.

Management of Atypical Slipped Capital Femoral Epiphysis

“…25 Pseudohypoparathyroidismrelated SCFE is exceedingly rare, with only a few cases reported in the literature and all presenting with bilateral SCFE. 14,33,34 Radiographic features of pseudohypoparathyroidism have been described as similar to those of hyperparathyroidism detailed above. 14…”

“…4,10 Clinical symptoms of hypothyroidism include bradycardia, fatigue, lethargy, cold intolerance, constipation, weight gain or inability to lose weight, dry skin, hair loss, memory impairment, and short stature. 11,14,15 This highlights the importance of ruling out an underlying endocrinopathy, even in the obese patient. Chronic hypothyroidism can also inhibit skeletal maturation and patients can present with a delayed bone age.…”

“…Many patients with hypothyroid-associated SCFE present prior to age 10, but there are a number of reported cases in older patients as well. 11,[14][15][16][17] Like other endocrinopathy-associated SCFEs, these patients often present with bilateral slips. 10 When a child with Down Syndrome presents with a SCFE, it is important to check thyroid levels due to the association of these disorders.…”

“…28 These changes can manifest on radiographs or MRI as an abnormal widening or irregularity of the physis. 14 Late manifestations can also include osteitis fibrosa cystica/brown tumors. 29 The most common etiology of primary hyperparathyroidism is parathyroid adenoma.…”

Association of Relative Skeletal Immaturity of the Triradiate Cartilage with Increased Proximal Femoral Deformity in Prophylactic Fixation for Slipped Capital Femoral Epiphysis: A Radiographic Study

“…It has been proposed that patients at high risk of a contralateral slip should undergo prophylactic fixation at initial presentation. Risk factors of contralateral slip include endocrinopathies such as hypothyroidism or panhypopituitarism, [14][15][16] patients younger than 10 years, 17 and instances where the operating surgeon believes there may be a notable delay in presentation should a subsequent slip occur. 17 Reported incidence of bilateral slips in SCFE patients on initial presentation is between 9% and 26%, and as such the debate regarding prophylactic fixation of the contralateral hip affects most patients who present with SCFE.…”