What are the symptoms of osteochondroma in the ankle?

Symptoms of Osteochondroma in the Ankle

Osteochondromas in the ankle are often asymptomatic and discovered incidentally, but when symptomatic, patients typically present with pain, palpable bony mass, swelling, and limited range of motion related to the lesion's size and anatomic location. 1, 2

Primary Clinical Manifestations

Asymptomatic Presentation:

• Most osteochondromas are found incidentally on imaging performed for other reasons 1, 3
• The lesion may remain clinically silent throughout the patient's life if small and non-impinging 4

Symptomatic Presentation:

• Pain is the most common symptom when present, particularly with activity or direct pressure on the lesion 5, 1
• Palpable bony mass or deformity that patients or clinicians can feel on examination 6, 3
• Swelling of the ankle joint or surrounding soft tissues 2
• Limited range of motion due to mechanical obstruction or joint irritation 2

Location-Specific Symptoms

Posterior Ankle Osteochondromas:

• Posterior ankle impingement syndrome with pain during plantarflexion 1
• Risk of fracture through the osteochondroma stalk due to persistent ankle motion, which can acutely worsen symptoms 1

Compression-Related Symptoms:

• Neurovascular compromise from compression of adjacent nerves or blood vessels 6
• Tendon irritation or dysfunction when the lesion impinges on surrounding tendons 6

Growth-Related Symptoms

• Osteochondromas typically grow until skeletal maturity (end of puberty when growth plates fuse) 5, 7
• New or increasing pain after skeletal maturity is concerning for malignant transformation to chondrosarcoma 5, 6
• Documented increase in lesion size after skeletal maturity warrants immediate evaluation for malignant transformation 5, 6

Red Flag Symptoms Suggesting Malignant Transformation

Critical warning signs that require urgent evaluation:

• Rapid growth of the lesion, particularly after skeletal maturity 5
• Increasing or new-onset pain in a previously stable or asymptomatic lesion 5, 6
• Cartilage cap thickness >2.0-3.0 cm on MRI or CT imaging 5

Common Pitfalls in Clinical Assessment

• Solitary osteochondromas have very low malignant transformation risk (<1%), but multiple osteochondromas carry a 30% lifetime risk of transformation to secondary chondrosarcoma 4
• Axial skeleton and proximal extremity locations (including proximal ankle/talus) have higher transformation risk than distal peripheral lesions 4, 6
• The time interval between initial diagnosis and malignant transformation can be prolonged, requiring long-term vigilance 6
• Recurrent osteochondromas after surgical excision have increased malignant potential and warrant closer surveillance 6

Associated Deformities in Multiple Osteochondromas

When part of hereditary multiple osteochondromas syndrome, patients may additionally present with:

• Short stature 5
• Angular deformities of long bones 5
• Leg length discrepancy 5
• Scoliosis 5