Slipped Capital Femoral Epiphysis in Primary Hyperparathyroidism - Case Report with Literature Review

Slipped capital femoral epiphysis as primary presentation in an adolescent with primary hyperparathyroidism due to ectopic mediastinal parathyroid adenoma

Key Clinical Message

Ectopic mediastinal parathyroid adenoma causes primary hyperparathyroidism presenting as hypercalcemia. When children with hypercalcemia present with slipped capital femoral epiphysis, a detailed evaluation for hypercalcemia must be done before surgery.

Abstract

The association between slipped capital femoral epiphysis (SCFE) and hyperparathyroidism has been reported and is rare. Each is known to affect different age groups. We report a case of a 13-year-old boy with SCFE and primary HPT leading to hypercalcemia and skeletal deformities.

Primary hyperparathyroidism in an adolescent presenting with genu valgus progressing to extensive bone disease; a case report

BACKGROUND

Primary hyperparathyroidism which is rare in adolescents presents commonly with non-specific symptoms and systemic complaints. Though there are few reported cases of genu valgus, genu valgus progressing to extensive bone disease despite mildly elevated calcium had not been reported before.

CASE PRESENTATION

A 12-year-old male had been evaluated for bilateral (left > right) genu valgus and short stature. Serum calcium and phosphate levels had been normal. X-ray of the femora and pelvic bones had not shown additional abnormalities. Valgus deformity progressed despite left femoral plating, and a left distal femoral medial closed wedge osteotomy had been performed at 15 years. Plain imaging at that time had shown localised osteopaenia. At the age of 17 years, he developed multiple fragility fractures of his left hip rendering him wheelchair-bound. Further evaluation revealed a serum PTH level of 2571 (10-65) pg/mL with calcium of 2.82 (2.2-2.6) mmol/L and inorganic phosphate of 1.7 (2.2-4.7) mg/dL. The lumbar spine DXA scan showed a Z-score of -5.8. A left parathyroid adenoma was localised and there was evidence of hyperparathyroid bone disease including brown tumours. He underwent left parathyroidectomy and left thyroid lobectomy after which his PTH level dropped to 4.03 pg/mL. He developed hypocalcaemia which was managed successfully with calcium and alfacalcidol replacement.

CONCLUSIONS

Primary hyperparathyroidism can present with genu valgus in adolescents. Initial normocalcaemia which could be due to concomitant vitamin D deficiency could mask this leading to delayed diagnosis until severe irreversible bone disease ensues.

Primary hyperparathyroidism from ectopic parathyroid adenoma in a 12-year-old with slipped capital femoral epiphysis

Primary hyperparathyroidism has been reported in pediatric patients presenting with slipped capital femoral epiphysis (SCFE), but never in patients with ectopic parathyroid adenoma. A 12-year-old boy with obesity and autism spectrum disorder presented with a limp and was found to have bilateral SCFE. Calcium was elevated to 12.3 mg/dL with parathyroid hormone (PTH) of 1191 pg/mL. Neck ultrasound revealed no parathyroid adenoma. He was discharged following bilateral surgical pinning with plans for outpatient workup. Repeat labs 5 days later demonstrated calcium had risen to 16.7 mg/dL. Technetium-99m sestamibi scintigraphy and a computed tomography scan revealed a 2.7 × 1.6 × 1.9 cm intrathymic mediastinal lesion. He underwent a thoracoscopic resection of the mass, and intraoperative PTH levels fell appropriately. Pathology revealed a parathyroid adenoma. Postoperatively, the patient developed hungry bone syndrome followed by normocalcemic secondary hyperparathyroidism which resolved with high-dose vitamin D supplementation. Primary hyperparathyroidism presenting as SCFE in a pediatric patient has been reported in 13 previous cases. This is the first reported case of bilateral SCFE arising from an ectopic parathyroid adenoma. Thoracoscopic resection is a relatively new approach in pediatrics. Primary hyperparathyroidism can be associated with SCFE, especially bilateral, and should be considered in patients with traditional risk factors for SCFE. Pediatric patients with primary hyperparathyroidism and negative neck imaging should be further evaluated for ectopic parathyroid adenomas with nuclear medicine or cross-sectional imaging that includes the head, neck, and mediastinum. Thoracoscopic resection can be considered in pediatric patients with mediastinal ectopic parathyroid adenoma.

Slipped Capital Femoral Epiphysis Associated with Endocrinopathy: A Narrative Review

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Slipped capital femoral epiphysis (SCFE) has a well-documented association with underlying endocrine conditions, including thyroid hormone aberrations and parathyroid dysfunction.

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Recombinant growth hormone therapy has also been identified as a risk factor for the development of SCFE.

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Presentation before their 10th birthday or after their 16th birthday along with height of <10th percentile are reliable risk factors for identifying children with an SCFE who are at a heightened risk for an underlying endocrinopathy and can been used to guide selective laboratory testing.

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Patients with unilateral SCFE presentations with an underlying endocrinopathy are at a heightened risk for contralateral slip development and should be treated with prophylactic fixation.

Diagnosis and Management of Unstable Slipped Capital Femoral Epiphysis: A Critical Analysis Review

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An unstable slipped capital femoral epiphysis (SCFE) is characterized by the inability to walk and is associated with a high risk of osteonecrosis.

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An unstable SCFE is less common than a stable SCFE; however, the demographics are similar in both groups of patients with SCFE.

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The diagnosis of an unstable SCFE is characterized by a history of antecedent pain and the inability to walk on examination, and it is confirmed by radiographic assessment.

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Management of an unstable SCFE includes closed reduction, open reduction, and capital realignment, which have all been noted to have lower rates of osteonecrosis than reported in historic reports.

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All management approaches have certain advantages and disadvantages, and comparative studies are needed to guide clinical decision-making.

Slipped Capital Femoral Epiphysis: Early Intervention and Referral

Slipped capital femoral epiphysis is the most common hip pathology in children aged 8-15 years old. Research has shown that when a nonorthopedic provider evaluates this patient population, there can be a significant delay in the appropriate treatment, which may have serious consequences for the prognosis of the patient. The delays are often caused by the practitioner's inability to put the clinical picture into focus with regard to how these patients typically present.. This article presents the demographics, clinical presentation, differential diagnosis, radiological and physical examination techniques, and prevention strategies to recognize this condition and provide early intervention.