Tibial nerve compression due to osteochondroma of the fibular head: A case report

RATIONALE: Osteochondroma is one of the most common primary benign bone tumors. In most cases, this disease is asymptomatic. However, it may become symptomatic owing to nerve and vascular compression when it affects the knee joint. Isolated tibial nerve palsy caused by proximal fibular osteochondroma is rare. PATIENTS CONCERNS: A 60-year-old male, was treated for degenerative arthritis of the right knee, referred to the right great toe flexion limitation that occurred 3 weeks prior. DIAGNOSES: Magnetic resonance imaging revealed compression of the tibial nerve and surrounding muscles due to an osseous lesion in the fibular head. A nerve conduction test confirmed tibial neuropathy in the right lower leg. INTERVENTIONS: Exploratory surgery was performed to decompress the tibial nerve and remove the bony lesion histopathologically diagnosed as an osteochondroma. OUTCOMES: Fifty-five months postoperatively, toe flexion recovered to normal. No recurrence of osteochondroma was observed. LESSONS: As in our case, if a bony lesion is diagnosed on radiographs with neurological symptoms, early decompression surgery is necessary. Moreover, since it can be misdiagnosed as a simple bony spur, magnetic resonance imaging and tissue biopsy are also indicated.