Shale-leggedness

Shale-leggedness is identified by an unusual fragility of the bones in the legs, either causing them to deform or shatter under stress.

Causes

It is unknown whence the condition comes from, it has however been observed that miners and less wealthy city-dwellers have a higher risk of contracting the disease, especially in the winter times.
Some scientists hypothesise that the condition is caused by insufficient light, the various colours combined to form white light also being present in bones, making them partially white instead of entirely grey.
How precisely this light manifests itself in the bones is not yet understood, though perhaps the stable, directional quality of a beam of light reinforces the bone and keeps it straight in a way we cannot understand.
Another even less likely possibility is that somehow darkness reduces the body's powers, similar to how a plant without light withers away.
Due to the vast difference in biology it is unlikely that this correlates, though a related reaction is theoretically possible.

Treatment

Being outside a lot has been proven to reduce the maladie's effects, though how exactly this works is hardly understood at all.
It has been observed that Dr Vonkler's all-liver oil can help alleviate symptoms and may even have preventative value, but further, independent research is required to find a definitive conclusion.
Scientists hypothesise that the mildly adhesive property of the medication helps to reinforce bones, reducing the risk of deformation of injury, while others believe that the pills act as a stimulant to the body's inner mechanisms, akin to bringing balance to a humour.

Affected Groups

The condition can affect all walks of life, although children are more likely to have deformation then brittleness in the legs and the elderly appear to have a greater amount of fractures.
Miners and other professionals who spend most of their time underground or in the darkness are at thought to be at risk.

Type

Physiological

Origin

Natural

Cycle

Short-term

Rarity

Uncommon