Hyperparathyroidism Skeletal Findings

Skeletal Findings in Metabolic Bone Diseases

• Skeletal findings in hyperparathyroidism are most readily recognized in the hand (31%)
• Subperiosteal bone resorption in hyperparathyroidism begins at the radial aspects of the middle phalanges
• Bone resorption can also occur in the ribs, lamina dura, humerus, femur, and upper medial tibia
• Trabecular, intracortical, endosteal, subchondral, and subligamentous or subtendinous bone resorption can also occur

Tumor-Induced Osteomalacia

• Generalized osteopenia, vertebral body fractures, and multiple Looser zones are characteristic of tumor-induced osteomalacia
• Fibroblast growth factor 23-secreting mesenchymal tumors can cause tumor-induced osteomalacia

Hypophosphatasia

• Hypophosphatasia is characterized by severe calvarial ossification defects
• Soft-tissue deposits of calcium hydroxyapatite, calcium pyrophosphate dihydrate, and calcium oxalate can occur around large joints

Amyloid Deposition

• Amyloid deposition can occur in patients undergoing long-term hemodialysis
• Amyloid deposition can lead to carpal tunnel syndrome in as many as 31% of patients

Primary Hyperparathyroidism

• Primary hyperparathyroidism can cause bone resorption, leading to osteopenia and Looser zones
• Jaw pain and bone deformities are common symptoms of primary hyperparathyroidism

Acromegaly

• Acromegaly can cause thick frontal bones and an enlarged sella
• Spade-shaped distal phalangeal tufts, an enlarged heel pad, and thick plantar skin are characteristic of acromegaly

Scurvy

• Scurvy is characterized by osteopenia, periosteal elevation, and metaphyseal beaking
• Frankel lines and Trummerfeld zones or scurvy lines reflect accumulation of hemorrhage in the zone of provisional calcification
• Subepiphyseal "corner" fractures can occur in scurvy