RESUMO
Background: In anterior lumbar interbody fusion (ALIF), the use of integrated screws is attractive to surgeons because of the ease of implantation and no additional profile. However, the number and length of screws necessary for safe and stable implantation in various bone densities is not yet fully understood. The current study aims to determine how important both length and number of screws are for stability of ALIFs. Methods: Three bone models with densities of 10, 15, and 20 pounds per cubic foot (PCF) were chosen as surrogates. These were instrumented using the Z-Link lumbar interbody system with either 2, 3, or 4 integrated 4.5 × 20 mm screws or 4.5 × 25 mm screws (Zavation, LLC, Flowood, MS). The bone surrogates were tested with loading conditions resulting in spine extension to measure construct stiffness and peak force. Results: The failure load of the construct was influenced by the length of screws (p=.01) and density of the bone surrogate (p<.01). There was no difference in failure load between using 2 screws and 3 screws (p=.32) or when using four 20 mm screws versus three 25 mm screws (p=.295). Conclusion: In our study, both bone density and length of screws significantly affected the construct's load to failure. In certain cases where a greater number of screws are unable to be implanted, the same stability can potentially be conferred with use of longer screws. Future clinical studies should be performed to test these biomechanical results.
RESUMO
A migraine is a clinical diagnosis with a presentation of one or more severe unilateral or bilateral headache(s) often preceded by an aura and typically accompanied by nausea, vomiting, photophobia, and/or phonophobia. This neurological disease is often debilitating and greatly affects the quality of life of those it inflicts. In fact, a recent study conducted by the Global Burden of Disease and published in The Lancet Neurology revealed that migraines ranked second to only back pain as the most disabling disease. Triggers for migraines have ranged from female sex, low socioeconomic status, and diet to loud noises, sleep hygiene, and stress. Along with its clinical presentation, laboratory tests and imaging help rule out other potential causes of the headache and lead to a diagnosis of migraine. Migraines are typically divided into three phases: prodromal, headache, and postdrome. The pathophysiology of each phase remains under investigation, with differing theories regarding their pathways. Existing therapies are abortive therapies for acute migraines or preventative therapies. Abortive therapy consists of NSAIDs and triptans. Preventative therapies include tricyclic antidepressants, calcium channel blockers, beta-blockers, and anticonvulsants. In this review, we focus on the role of NSAIDs and the COX-2 inhibitor, celecoxib oral solution, for the abortive treatment of acute migraines.
