My mother is my first teacher.

My mother makes a lunch box for me every day.

He injured his knee joint.

His articular cartilage has worn down due to age.

He clenched his fists in anger, his knuckles turning white.

A hinge joint, like the human elbow or knee, is a type of joint that only bends in one direction.

She is suffering from temporomandibular joint disorder.

My grandmother has been suffering from arthritis for many years.

My eye pain is so severe that it's hard for me to look at the computer screen.

Recently, I can't concentrate on my work because of severe shoulder pain.