Stress shielding refers to the reduction in bone density

Bone density

Bone density is a medical term normally referring to the amount of mineral matter per square centimeter of bones. Bone density is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk.This medical bone density is not the true physical "density" of the bone, which...

 (osteopenia

Osteopenia

Osteopenia is a condition where bone mineral density is lower than normal. It is considered by many doctors to be a precursor to osteoporosis. However, not every person diagnosed with osteopenia will develop osteoporosis...

) as a result of removal of normal stress from the bone by an implant (for instance, the femoral component of a hip prosthesis

Hip replacement

Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. Hip replacement surgery can be performed as a total replacement or a hemi replacement. Such joint replacement orthopaedic surgery generally is conducted to relieve arthritis pain or fix severe...

). This is because by Wolff's law

Wolff's law

Wolff's law is a theory developed by the German Anatomist/Surgeon Julius Wolff in the 19th century that states that bone in a healthy person or animal will adapt to the loads it is placed under. If loading on a particular bone increases, the bone will remodel itself over time to become stronger...

, bone in a healthy person or animal will remodel in response to the loads it is placed under. Therefore, if the loading on a bone decreases, the bone will become less dense and weaker because there is no stimulus for continued remodeling that is required to maintain bone mass.

External links

• Stress shielding, Online Medical Dictionary.