Wolff’s Law: The Fundamentals
In 1892, German orthopedic surgeon Julius Wolff proposed the Law of Transformation of the Bone, which came to be known as Wolff’s Law. In his proposal, Wolff postulated that bones adapt to the stress under which they are placed. For instance, if a bone is constantly subjected to outside forces, its density — and therefore its strength — will increase so that it can cope. Conversely, Wolff theorized that if a bone is not regularly stressed, it will become weaker and less dense, leaving it prone to fracture.
Later, in the 1960’s, American orthopedist Harold Frost refined Wolff’s Law with the Mechanostat model, which he described in the Utah Paradigm of Skeletal Physiology. His work went into even greater detail, specifying that both bone density and bone geometry are affected by outside stresses, and that bone gain is caused specifically by local mechanical deformation of bone due to these outside stresses. Bone weakness, in contrast, is precipitated by a lack of regular elastic deformation of the bone.
To make this more clear, consider the following familiar examples:
- Because most tennis players rely more heavily on their dominant arm when they play, the bones in that arm are subjected to more stress and therefore grow stronger than the bones in the other arm.
- Long distance runners who increase their mileage too quickly are more likely to suffer from stress fractures, since their bones are not accustomed to the increase in mechanical force from the extra miles of pounding.
- Older women are encouraged to engage in weight-bearing activities, like stair-stepping and snow-shoveling, in order to combat bone loss after menopause.
Justifying Pediatric Chiropractic Care with Wolff’s Law
Childhood is a critical period for bone growth and development, and kids’ bones are constantly under stress. Whether they are running around the backyard, climbing playground equipment or playing on the soccer team, active kids are inducing the elastic deformation of the bone that will lead to an increase in density and strength.
In general, that’s great news, but there’s a catch. If the child has mechanical imbalances — like running with a slight limp, or habitually hanging their head to one side — some bones might not be subjected to the appropriate amount of force, while others get too much exercise. Not only can this increase the likelihood of bone fracture if a child gets tripped during a soccer game or falls off the monkey bars, but it could also have long-term implications for growth and development.
Pediatric chiropractic care supports proper mechanical alignment, ensuring that bones are subjected to an adequate amount of force so that they develop properly and grow strong. Regardless of the child’s age, maintaining this balance can help prevent future skeletal issues and injuries.Share