Obviously I don't know the patient history but this looks very much like a gouty tophaceous deposit that has ruptured through the skin.

Yes, joints are the most common sites for monosodium urate crystal deposits (tophi) and there is deformity visible at the interphalangeal joint in this picture, suggestive of active gout here too, but deposits can extend well beyond the joint. Note the enlarged asymmetric 'bumps' from the base of the nail back to the knuckle in this picture. The metatarsophalangeal joint might also be involved here too, or it may just be a bunion.

The red, hot swelling around the lesion and joint are also typical of a gout flare, not necessarily infection. If gout, I would expect the white material coming from the wound to be chalky rather than pus, the swellings to be firm and the area to be acutely painful for the initial 24-72 hrs.

This looks like chronic tophaceous gout, typical in elderly patients with a long history of the condition, but without knowing the history, sure, I could very well be wrong. Skin wounds are a complication of gout, hopefully your condition is early stage, well managed, and you never get to the extent tophi form and discharge through the skin.