Epidemiology

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Etiology

Primary (Idiopathic) Hypertrophic Osteoarthropathy (Pachydermoperiostosis, Touraine-Solente-Gole Syndrome)

• Hereditary Disorder Which Presents in Childhood
• Similar Clinical Features to that of Secondary Hypertrophic Osteoarthropathy

Secondary Hypertrophic Osteoarthropathy

Pulmonary

• Cystic Fibrosis (CF) (see Cystic Fibrosis, [[Cystic Fibrosis]])
• Lung Cancer (see Lung Cancer, [[Lung Cancer]])
  • Epidemiology
    • Most Commonly Associated with Adenocarcinoma Histology in Lung Cancer
    • Less Frequently Associated with Small Cell Lung Cancer
• Pulmonary Infection

Other

• Arterial Vascular Prosthetic Infection
  • Epidemiology: rare etiology
  • Clinical
    • Clubbing or Periosteal New Bone Formation Isolated to a Single Upper Extremity: in cases with an upper extremity arterial prosthetic
    • Clubbing or Periosteal New Bone Formation in Unilateral Lower Extremity: in cases with an arterial graft to the lower extremity
    • Clubbing or Periosteal New Bone Formation in Bilateral Lower Extremities: in cases with an aortic prosthetic graft
• Cirrhosis (see End-Stage Liver Disease, [[End-Stage Liver Disease]])
  • Epidemiology: uncommon etiology
• Hodgkin’s Disease (see Hodgkin’s Disease, [[Hodgkins Disease]])
  • Epidemiology: uncommon etiology
• Right-to-Left Intracardiac Shunt

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Physiology

• Abnormal Proliferation of the Skin and Osseous Tissue at the Distal Parts of the Extremities
  • Clubbing and Hypertrophic Osteoarthropathy are Different Clinical Manifestations of the Same Disease Process
  • Pathogenesis Involves Activation of the Platelet-Endothelial Cells, with Subsequent Release of Fibroblast Growth Factor (Platelet-Derived Growth Factor)

Pathogenesis of Primary Hypertrophic Osteoarthropathy

• Elevation in Circulating Prostaglandin E2 Due to Mutation in the HPGD gene Which Encodes 15-Hydroxyprostaglandin Dehydrogenase: this is the primary enzyme responsible for prostaglandin degradation

Pathogenesis of Secondary Hypertrophic Osteoarthropathy Associated with Lung Cancer (Possible Mechanisms)

• Megakaryocytes May Escape the Normal Fragmentation to Platelets in the Lung, Reaching the Distal Extremities Where they Release Growth Factors
• Tumor Production and Release of a Factor Which Induces the Manifestations of Hypertrophic Osteoarthropathy (Such as Vascular Proliferation, Edema Formation, and New Bone Formation)
• Possible Increase in PGE2 (Similar to that Observed in Primary Hypertrophic Osteoarthropathy)
  • In Cystic Fibrosis: serum prostaglandin concentrations are higher in those with clubbing compared with those without clubbing
  • Unresectable Lung Cancer: overproduction of PGE2 has been demonstrated

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Diagnosis

X-rays of Long Bones (Tibia, Fibula)

• Demonstrates Characteristic Periosteal New Bone Formation

PET Scan (see Fluorodeoxyglucose-Positron Emission Tomography, [[Fluorodeoxyglucose-Positron Emission Tomography]])

• Demonstrates Diffuse Uptake by the Long Bones

Bone Scan (see Bone Scan, [[Bone Scan]])

• Demonstrates Diffuse Uptake by the Long Bones

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Clinical Manifestations

Rheumatologic Manifestations

• Clubbing (see Clubbing, [[Clubbing]])
• Painful Arthropathy
  • Epidemiology
    • May Occur in Some Cases: mimicking an inflammatory arthritis
    • May Precede the Onset of Clubbing
  • Most Commonly Involved Joints
    • Ankles
    • Elbows
    • Knees
    • Wrists
  • Less Commonly Involved Joints
    • Metacarpal Joints
    • Metatarsal Joints
    • Phalangeal Joints
• Periostosis of Tubular Bones: usually associated with pain on palpation of the involved area
• Synovial Effusions (see xxxx, [[xxxx]]): most prominent in the large joints

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Treatment

Analgesia

• Non-Steroidal Anti-Inflammatory Drug (NSAID) (see Non-Steroidal Anti-Inflammatory Drug, [[Non-Steroidal Anti-Inflammatory Drug]])

Bisphosphonates (see Bisphosphonates, [[Bisphosphonates]])

• Agents
  • Pamidronate (xxx) (see Pamidronate, [[Pamidronate]])
  • Zoledronate (xxx) (see Zoledronate, [[Zoledronate]])
• Clinical Efficacy
  • Highly Effective (Per Case Reports) in Refractory Cases

Treatment of Primary Disorder

• Lung Cancer Resection, etc: usually results in regression of symptoms, but is not always effective

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References

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