Spondylolysis is a common cause of low back pain in preadolescents and adolescent athletes, as it accounts for about 50% of all low back pain. It is believed that both repetitive trauma and an inherent genetic weakness can make an individual more susceptible to spondylolysis. Risk factors
Sports involving repetitive or forceful hyperextension of the spine, especially when combined with rotation are the main mechanism of injury for spondylolysis. The stress fracture of the pars interarticularis occurs on the side opposite to activity. For instance, for a right-handed player, the fracture occurs on the left side of the vertebrae.Spondylolysis has a higher occurrence in the following activities:
Baseball
Military service
Tennis
Diving
Cheerleading
Gymnastics
Gridiron Football
Association Football
Wrestling
Weightlifting
Roller Derby
Cricket
Pole Vault
Rugby
Volleyball
Gym
Ultimate Frisbee (especially during impact from laying out)
Ballet
Muay ThaiAlthough this condition can be caused by repetitive trauma to the lumbar spine in strenuous sports, other risk factors can also predispose individuals to spondylolysis. Males are more commonly affected by spondylolysis than females. In one study looking at youth athletes, it was found that the mean age of individuals with spondylolisthesis was 20 years of age. Spondylolysis also runs in families suggesting a hereditary component such as a predisposition to weaker vertebrae. Pathophysiology
Spondylolysis is a bony defect or fracture within the pars interarticularis of the vertebral arch in the spinal column. The vast majority of spondylolysis occur in the lumbar vertebrae, however it can also be seen in cervical vertebrae.
Interferon beta-1b is a cytokine in the interferon family used to treat the relapsing-remitting and secondary-progressive forms of multiple sclerosis (MS). It is approved for use after the first MS event. Closely related is interferon beta 1a, also indicated for MS, with a very similar drug profile. Mechanism of action
Interferon beta balances the expression of pro- and anti-inflammatory agents in the brain, and reduces the number of inflammatory cells that cross the blood brain barrier. Overall, therapy with interferon beta leads to a reduction of neuron inflammation. Moreover, it is also thought to increase the production of nerve growth factor and consequently improve neuronal survival. Side effects
Interferon beta-1b is available only in injectable forms, and can cause skin reactions at the injection site that may include cutaneous necrosis. Skin reactions vary greatly in their clinical presentation. They usually appear within the first month of treatment albeit their frequence and importance diminish after six months of treatment. Skin reactions are more prevalent in women. Mild skin reactions usually do not impede treatment whereas necroses appear in around 5% of patients and lead to the discontinuation of the therapy. Also over time, a visible dent at the injection site due to the local destruction of fat tissue, known as lipoatrophy, may develop. Interferons, a subclass of cytokines, are produced in the body during illnesses such as influenza in order to help fight the infection. They are responsible for many of the symptoms of influenza infections, including fever, muscle aches, fatigue, and headaches.