What is the common finding in osteoarthritis involving fingers?

In osteoarthritis, particularly in the fingers, one of the hallmark findings is the presence of Bouchard's nodes. These are bony enlargements located at the proximal interphalangeal joints (PIP) and are a direct result of the degenerative changes and hypertrophy in this joint due to osteoarthritis.

As the cartilage wears down, the body reacts by developing new bone growth in an attempt to stabilize the joint, leading to these characteristic nodes. Bouchard's nodes are often seen alongside a similar finding known as Heberden's nodes, which occur at the distal interphalangeal joints (DIP). The presence of these nodules helps indicate osteoarthritis as opposed to other forms of arthritis, where different patterns of joint involvement and symptomatology may be present.

Other options, such as deformities of the metacarpals and ulnar deviation, are more characteristic of rheumatoid arthritis rather than osteoarthritis. Swollen gums are not relevant to joint pathology and do not occur in osteoarthritis.