Periostitis blade of a horned dinosaur. Periostitis Periostitis, also known as periostalgia, is a medical condition caused by inflammation of the periosteum, a layer of connective tissue that surrounds bone. The condition is generally chronic, and is marked by tenderness and swelling of the bone and pain. Acute periostitis is due to infection, is characterized by diffuse formation of pus, severe pain, constitutional symptoms, and usually results in necrosis. It can be caused by excessive physical activity as well, as in the case of medial tibial stress syndrome (also referred to as tibial periostalgia, soleus periostalgia, or shin splints). Congenital infection
Medial meniscus During rotational movements of the tibia (with the knee flexed 90 degrees), the medial meniscus remains relatively fixed while the lateral part of the lateral meniscus is displaced across the tibial condyle below. The medial meniscus separates the tibia and femur to decrease the contact area between the bones, and serves as a shock absorber reducing the peak contact force experienced. It also reduces friction between the two bones to allow smooth movement in the knee and distribute load during movement. Acute injury to the medial meniscus frequently accompanies an injury to the ACL (anterior cruciate ligament) or MCL (medial