Purpose <p>- As a potential cause of compression resulting in neuropathic pain or using to secure coxal bone procedure, the proximity of sciatic nerve against coxal bone inside the infra-piriform foramen was unclear.</p> Methods <p>- This systematic review focused on the relationship between pelvic bone and sciatic nerve based on PRISMA methodology.</p> Results <p>- A total of 26 studies involving 4,813 lower limbs were included in the meta-analysis. The variations of the sciatic nerve in relation to the piriform muscle were described in 14.5% of cases. The variation involving division of the sciatic nerve in the pelvis, with the common fibular nerve passing over the piriformis muscle and the tibial nerve passing through it, was never observed. However, a variation in which the sciatic nerve divided in the pelvis, with its two terminal branches (the common fibular nerve and the tibial nerve) passing separately under the piriformis muscle, was described in 0.81% of cases.</p> Conclusion <p>- There was no data available to analyse the distance between the sciatic nerve and the coxal bone as it exited the pelvis.</p>