Causes of Spondylolysis
Most often, spondylolysis is caused by stress fractures. In such cases, this is known as isthmic spondylolysis. The vertebrae are most vulnerable to this when the pars interarticularis sustains force when it is in an extended position. This might occur when you land a jump, for instance.

Another spondylolysis cause can be present from birth (dysplastic or congenital spondylolysis) in which your vertebrae may be thinner than normal vertebrae, making it more prone to fractures. It also may occur due to degenerative changes in the spine or trauma such as a fall or accident can also attribute to spondylolysis.

As mentioned previously, those who are older or who play high-contact sports are at a great risk for spondylolysis compared to others. Typically, this is in adolescents between the ages of 10 to 15 who overuse or hyperextend their lower back due to sports and activities such as gymnastics, diving, football, or weightlifting.

For older individuals, degeneration of the facet joints and the discs in their spine put them at a greater risk of developing this condition. In addition, having osteoporosis (which is an effect of the aging process) makes you more susceptible to stress fractures or breaks.