Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It only takes a minute to sign up.
Sign up to join this community
A woman I know has been losing height at a rate of few cm a year following a severe spinal injury. How is this possible? What kind of injury could cause such progressive loss of height? Could this be a genetic defect? Are there any disorders that cause this type of shrinking?
In case it could be relevant, her brothers are very tall.
As @WYSIWYG pointed, muscular atrophy is the main cause for height decrease.
A spine injury leads to neural impairment and paresis / paralysis. This affects directly muscular trophism. It also limits physical activity, this being another favoring factor for muscular atrophy and overweight issues [1]. Association of bone degenerative processes (osteoporosis, osteopathy, osteolysis) is also a factor and it is dangerous because it promotes spinal cord injuries if vertebral height reduction amount is notable [2].
Focusing on muscular atrophy, here is how it can decrease height: by increasing vertebral column curvatures mostly on the upper region with articulating vertebrae. The vertebral column tends to gain a spring-like, spiral shape, associating accentuated cervical lordosis, accentuated thoracic kyphosis and thoracic scoliosis.
Image source: Scoliosis Treatment Alternatives. Chiropractic for Scoliosis Treatment Review (2014). Accessed 21.07.2014
While reading the comments to the question I found something interesting:
we know that the brain tells the body to grow, would a shock or something make the brain tell your body to shrink instead of growing?
Yes, the brain (hypotalamus) initiates a neuroendocrine response that leads to growth hormone secretion. The secretion is about 700 micrograms/day in a young adolescent, while in a healthy adult it is about 400 micrograms/day [3]. The deficiency in an adult person leads to a tendency of fat mass increase and a relative decrease in muscle mass and, in many instances, decreased energy and quality of life [4]. The brain can't "tell your body to shrink", but the lack of "communication" between the brain and organs leads to less to absolutely no use of that organ, thus inducing atrophy. The lack of both external and internal stimuli leads to atrophy (in general) [5].
References:
