cartoon courtesy of Hallmark

A 67-year-old female, physically active as a competitive tennis player, came to the Clinic for consultation, complaining of right knee pain .  She states she does not like the “grating sound” heard upon flexing her knee.

A review of her medical history discloses she is a non-smoker and an occasional consumer of alcoholic beverages.  She is otherwise in good health.  She takes anti-inflammatory medications for her pain .
She says she does not like all the sounds that the knee makes.

Discussion:
 

The patient experiences symptoms known as “Crepitus,” a medical term describing grating, crackling or popping sounds.  They can be accompanied by internally-experienced sensations of a scraping-like movement between joints beneath the skin surface.

Crepitus can be created when two rough surfaces of the joints come into direct contact with each other, most commonly caused in the knee by the decrease or total absence of cushioning material between coordinating elements, like the femur and tibia  

The resulting noise and sensation are often experienced in the early stages of Osteoarthritis of the knee, and are normally due to a deterioration or absence of cartilage and meniscus in the knee joint structure.