A 33-year-old woman presents with a hard, fixed nodule of the left lower leg. She states that it developed approximately 2 years ago after she fell and hit her leg on a table. She is otherwise healthy and does not take any medications. On examination, a firm 1-cm nodule of the left lower leg is noted. The nodule is non-tender with a slightly bluish tint to the overlying skin.
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Osteoma cutis is an uncommon condition characterized by osseous nodule formation in normal skin. It is seen more frequently in females, although the etiology remains unclear.1 The disorder is divided into two forms: primary and secondary. Primary osteoma cutis is associated with several genetic disorders. Albright hereditary osteodystrophy is the most common disorder and is characterized by cutaneous ossification, short stature, brachydactyly, obesity, and mental retardation. Secondary osteoma cutis is associated with a pre-existing lesion, trauma, or inflammatory process.2
Osteoma cutis can present anywhere on the body but most commonly occurs on the scalp, face, and extremities. Differential diagnosis includes cartilaginous tumors of the skin and reaction to a foreign body. Treatment of choice is surgical excision. Erbium laser has been used in some cases, but it can leave hypopigmentation. Children with multiples lesions warrant evaluation to rule out underlying syndrome association.3,4
Rebecca Geiger, PA-C, is a physician assistant on staff at the DermDox Dermatology Center in Hazleton, Pennsylvania. Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia.
- 1. Alhazmi D, Badr F, Jadu F, Jan AM, Abdulsalam Z. Osteoma cutis of the face in CBCT images [published online May 30, 2017]. Case Rep Dent. doi: 10.1155/2017/8468965
- 2. Caravaglio JV, Gupta R, Weinstein D. Multiple military osteoma cutis of the face associated with Albright hereditary osteodystrophy in the setting of acne vulgaris: A case report. Dermatol Online J. 2017;23(3).
- 3. Lennox L. Osteoma cutis. Updated January 25, 2017. Accessed September 6, 2017.
- 4. Coutinho I, Teixeira V, Cardoso JC, Reis JP. Plate-like osteoma cutis: nothing but skin and bone? [published online May 5, 2014] BMJ Case Rep. doi:10.1136/bcr-2013-202901