In association with osteoarthritis of the knee, a degenerative enthesopathy may occur on the anterior aspect of the patella. Among the manifestations is bone growth at the site of attachment of the quadriceps apparatus, which leads to patellar whiskering, also termed the tooth sign.
Similar bone proliferation at the sites of tendon and ligament attachment to bone is seen in the pelvis (especially the iliac crest, ischial tuberosity and trochanters) and occurs in patients with diffuse idiopathic skeletal hyperostosis DISH .
In psoriatic arthritis, irregular periosteal new bone formation leads to whiskering in the interphalangeal joints of the hand.
DR
