Osteocartilaginous exostosis

Osteocartilaginous exostosis
Synonyms	Osteochondroma
Pronounce	N/A
Specialty	N/A
Symptoms	Painless bony growth, possible nerve compression
Complications	Malignant transformation, vascular compromise
Onset	Childhood to adolescence
Duration	Lifelong
Types	N/A
Causes	Genetic mutations, hereditary factors
Risks	Family history, genetic predisposition
Diagnosis	X-ray, MRI, CT scan
Differential diagnosis	N/A
Prevention	N/A
Treatment	Surgical removal, monitoring
Medication	N/A
Prognosis	Generally good, with low risk of malignancy
Frequency	N/A
Deaths	N/A

Osteocartilaginous exostosis, also known as osteochondroma, is a common benign bone tumor characterized by an abnormal growth of bone and cartilage. It typically arises during periods of rapid skeletal growth, such as childhood and adolescence.

Epidemiology

Osteocartilaginous exostosis is the most common benign bone tumor, accounting for 20-50% of all benign bone tumors. It is more prevalent in males than females, with a male-to-female ratio of approximately 1.5:1. The condition often presents in individuals between the ages of 10 and 30.

Etiology

The exact cause of osteocartilaginous exostosis is not fully understood, but it is believed to be related to genetic mutations. The condition can occur sporadically or as part of a hereditary disorder known as Hereditary Multiple Exostoses (HME), which is an autosomal dominant condition caused by mutations in the EXT1 or EXT2 genes.

Pathophysiology

Osteocartilaginous exostosis arises from the growth plate, or physis, of long bones. It is composed of a bony stalk covered by a cartilage cap. The growth of the exostosis is thought to be due to aberrant endochondral ossification, where cartilage is abnormally converted into bone.

Clinical Presentation

Most patients with osteocartilaginous exostosis are asymptomatic and the condition is often discovered incidentally. When symptoms do occur, they may include:

• A palpable, painless bony mass
• Discomfort or pain due to mechanical irritation
• Nerve compression leading to neurological symptoms
• Vascular compromise if the exostosis impinges on blood vessels

Diagnosis

The diagnosis of osteocartilaginous exostosis is primarily based on imaging studies. The following modalities are commonly used:

• X-ray: Typically shows a bony outgrowth with a cartilage cap, often projecting from the metaphysis of long bones.
• MRI: Useful for assessing the cartilage cap thickness and any associated soft tissue involvement.
• CT scan: Provides detailed information about the bony structure and can help in surgical planning.

Differential Diagnosis

Conditions that may mimic osteocartilaginous exostosis include:

• Chondrosarcoma
• Enchondroma
• Fibrous dysplasia
• Non-ossifying fibroma

Management

The management of osteocartilaginous exostosis depends on the presence and severity of symptoms. Options include:

• Observation: Asymptomatic lesions are often monitored with periodic imaging.
• Surgical removal: Indicated for symptomatic lesions, cosmetic concerns, or suspicion of malignant transformation.

Prognosis

The prognosis for individuals with osteocartilaginous exostosis is generally excellent. The risk of malignant transformation to chondrosarcoma is low, estimated at less than 1% for solitary lesions and 1-5% for those with hereditary multiple exostoses.

Complications

Potential complications of osteocartilaginous exostosis include:

• Malignant transformation
• Fracture of the exostosis
• Vascular or nerve compression

See Also

• Hereditary Multiple Exostoses
• Bone tumor
• Chondrosarcoma

External Links

• [Link to relevant medical resources]