Incidental Osteopoikilosis in an Ankle Fracture Patient: Case Report and Literature Review

Osteopoikilosis (OPK) is a benign osteosclerotic dysplasia that is almost always asymptomatic. Its radiographic pattern can mimic osteoblastic metastases. Its coexistence with fractures is rare, and there is no demonstrated increased risk of fracture or issues with bone healing. Our objective was to present a case of an ankle fracture with an incidental finding of OPK and highlight its clinical implications.

A 21-year-old male presented with pain and swelling after twisting his left ankle. X-rays and computed tomography (CT) scan revealed a comminuted medial malleolus fracture and avulsion of the lateral process of the talus, in addition to multiple well-defined sclerotic foci in the distal tibia, fibula, and talus, consistent with OPK. Laboratory tests were normal, except for vitamin D at 17 ng/mL. No associated endocrinological or rheumatological findings were noted. Open reduction and internal fixation of the medial malleolus was performed using 2.5 mm headless cannulated screws. The outcome was favorable with no pain, full bone healing, 0° dorsiflexion, and 60° plantar flexion at 17-month follow-up.

OPK shows symmetric epimetaphyseal images, with no periosteal reaction or soft tissue involvement; recognizing this pattern prevents unnecessary invasive studies and anxiety due to differential diagnosis with metastases. In fractures, management should follow standard orthopedic principles, as OPK does not affect biomechanics or healing.

OPK is a "do not touch" lesion; diagnosis is based on radiographs or CT scans, differentiating it from malignant processes. In concurrent fractures, standard treatment yields successful results.