Two goals in four minutes just after the half-hour mark from Miranda and Raul Garcia had Diego Simeone's men in a commanding position, but Roland Lamah reduced the arrears just before half-time with a lovely curling effort from outside the area.
However, it seemed only a matter of time before Radamel Falcao would get his customary goal and he made it 17 in his past 11 games for club and country 17 minutes from time with a controlled volley from Juanfran's cross.
Atleti have now won 12 games in a row in all competitions and moved level with Barca on 25 from a possible 27 points at the top.
They were never seriously troubled by an Osasuna side that have now lost on all five of their away journeys this season.
Raul Garcia should have given the hosts the lead as early as the sixth minute when he met Filipe Luis' cross from the left but Andres Fernandez produced a great save to keep the scores level.
Cristian Rodriguez then saw two efforts from distance turned away by Andres but the breakthrough came on 31 minutes when Gabi's free-kick from the left was brilliantly flicked into the far corner of the net by Miranda.
Moments later it was two as Alejandro Arribas only succeeded in heading the ball straight to Raul Garcia in his attempt to clear and the former Osasuna man fired home from just inside the area.
However, the Europa League holders were pegged back three minutes before half-time when Lamah collected a loose ball 25 yards from goal and curled an effort high into Thibaut Courtois' top-right hand corner.
Diego Godin headed just wide with the chance to restore Atleti's two-goal cushion six minutes after the break before Courtois was called into action to prevent Emiliano Amrneteros' drive bringing the visitors level.
However, the game was ended as a contest when Falcao stayed onside to volley home Juanfran's cross in behind the Osasuna defence from close range.
Kike Sola should have pulled another goal back for Osasuna as he headed over when unmarked from a corner with nine minutes to go but there were no further scares for Atleti as Osasuna remain rooted to the foot of the table.