A radiological image of loose body in the knee diagnosed as chondroma

A 45-year-old female came with complaints of pain and swelling over her right knee for five months. Initially, it was a size of a peanut, and it gradually increased to its current size. On clinical examination, there was a hard solitary swelling of 3x3 cm inferior to the patella. The swelling was mobile, non-compressible, and irreducible, the size of the swelling reduced on flexion. Knee movements flexion 0° to 130° with mild localized swelling over the anterolateral side of the knee, but she experienced a painful range of motion from 110° to 130°. Ligamentous integrity was normal. Radiographic investigation showed a right single well-defined loose body in the right knee with central lytic and peripheral sclerotic margin in the right knee. Diagnostic arthroscopy was performed, and a bony lesion was found in the infrapatellar pouch. The lesion showed benign characteristics and was then removed en bloc arthroscopically. Histopathological examination of the lesion confirmed chondroma. Chondromas in the knee usually occur due to minor trauma or friction, and its direct removal is the most appropriate management modality. The symptoms of the patient resolved post-operatively and on follow-ups.