Skeletal Sarcoid
Osseous Manifestations of Sarcoidosis

General Considerations

• Radiographic evidence of osseous involvement occurs in about 5% of patients with sarcoidosis
  • Arthralgia in patients with sarcoid may occur in up to 1/3 of patients
• Patients are usually between 20-40, more frequently women
• Typically affects multiple joints
• Most often affects hands, feet and ankles (the latter in acute form)
  • Lesions in long bones, skull or spine are rare
• Often occurs in association with pre-existing pulmonary and/or skin lesions such as lupus pernio
  • Purplish, indurated macules or papules on the face considered classic for sarcoid
• May occasionally be presenting manifestation of sarcoid

Clinical Findings

• Frequently asymptomatic
• Joint manifestations include
  • Stiffness
• Pain
• Soft tissue swelling
• Soft tissue nodules (granulomas)
• Erythema nodosum, especially in acute form

Imaging Findings

• Usually bilateral and symmetric
• Middle and distal phalanges of hands and feet most frequent sites of involvement
  • Tends to spare the wrists
• Distal portions of small bones of hands and feet tend to be affected first
• Patterns of osseous sarcoidosis
  • Small, cortical, punched-out lytic lesions, usually well-corticated,  in the phalangeal heads are most common manifestation
• Some been described as heart-shaped as in this case
• Reticular (permeative) pattern produces a lace-like (driftwood) pattern of destruction
• Acro-osteosclerosis of the terminal phalanges (bone stones)
• Not specific but can occur in up to 50% of patients with sarcoid of hands
• May represent healing phase
• Acro-osteolysis resembling scleroderma
• Bone destruction with pathologic fractures
• Usually with soft tissue swelling but without periosteal reaction
• Subperiosteal resorption resembling hyperparathyroidism
• Soft tissue nodules
• Although plain films are usually adequate to make the diagnosis, MR may show additional or unsuspected lesions in bone and soft tissues

Differential Diagnosis

• Scleroderma
  • Sarcoid lacks calcinosis circumscripta
• Rheumatoid arthritis
• Gout
  • Not usually symmetric and bilateral

Treatment

• Corticosteroids may decrease pain and swelling
• Bone changes are irreversible in chronic form

Prognosis

• Chronic osseous involvement is usually associated with diseases of other organs and has a poor prognosis
  

Sarcoid of feet. Frontal radiographs of both feet show multiple punched-out lytic lesions (red arrows) (one heart-shaped-white arrow), mostly in the proximal phalanges of both feet. There is also bone destruction and pathologic fractures of both third toes and the distal right 5th toe (black arrows).
For more information, click on the link if you see this icon
For this same photo without the annotations, click here

Radiographic, angiographic and radionuclide manifestations of osseous sarcoidosis.

Yaghmai, I. RadioGraphics Volume 3, Number 3 September 1983 pp. 375

Sarcoidosis: A Primary Care Review. Belfer, M; Stevens, R.  American Family Physician. December 1998

Sarcoid of bones  www.Gentili.net