Paget Disease Overview and Imaging Findings

Paget disease is commonly found in patients under the age of 50.

Lytic lesions in Paget disease exhibit a flame or blade of grass shape on imaging.

Sclerotic bone in Paget disease can be identified as an 'ivory vertebra' on imaging.

A common initial symptom of Paget disease is sharp pain in the affected bones.

Elevated ALP levels with normal calcium and phosphate levels are typical diagnostic findings in Paget disease.

Cranial nerve palsies can occur in Paget disease due to compression at neural foramina.

High output cardiac failure is a common and typical presentation of Paget disease.

Paget disease results in disordered bone structure, which is generally stronger than normal bone.

Sarcomatous degeneration in Paget disease generally leads to a good prognosis.

Coarsening of the trabeculae and cortices is a hallmark observed in Paget disease radiological findings.

Paget Disease Overview

Paget disease is a common musculoskeletal abnormality, typically affecting individuals 50 years and older.
Characterized by polyostotic (multiple bones involved), asymmetric disordered bone remodeling.
Intense osteoclastic (bone breakdown) activity precedes osteoblastic (bone formation) activity, resulting in lytic lesions then sclerotic bone.

Imaging Findings

Lytic Phase: Radiolucent areas, often flame or blade-of-grass shaped, along the diaphysis (shaft of long bones). Skull may exhibit osteoporosis circumscripta (large lucent areas).
Mixed Phase: Combination of lytic and sclerotic features.
Sclerotic Phase: Densely sclerotic (hardened) bone, like the classic "ivory vertebra".

Clinical Presentation

Asymptomatic: Often an incidental finding.
Symptomatic: May present with elevated alkaline phosphatase (ALP) levels with normal calcium and phosphate. A pathological fracture is possible as altered bone structure leads to weakened bone.
Other Symptoms: Cranial nerve palsies (compression at nerve openings), enlarged head/hat size (Tam O'Shanter sign), high output cardiac failure (rare case), and pain (often not the primary symptom). Pain may be associated with osteoarthritis.

Radiological Characteristics

Bony Expansion: The bone visually enlarges.
Trabecular and Cortical Coarsening: The internal and external bone structure becomes more irregular.
Bone Scan: Active lesions show increased blood flow and higher uptake on bone scans.

Complications & Prognosis

Sarcomatous Degeneration: Conversion of affected bone to osteosarcoma, malignant fibrous histiocytoma, or chondrosarcoma carries a poor prognosis. Watchful monitoring of known lesions is crucial.
Suspicion: New soft tissue components or new lysis in previously sclerotic bone should raise concern.

Explore the key aspects of Paget disease, a musculoskeletal disorder primarily affecting older adults. This quiz covers clinical presentations, imaging findings, and the distinct phases of bone remodeling associated with the disease.