FLC OF A B757 RETURNED TO LAND FOR EMER MEDICAL SVC FOR A CABIN ATTENDANT AND PAX DUE TO GOING THROUGH SEVERE TURB.

Narrative

WHILE ENRTE TO PAP AT FL330; WE WERE DEVIATING AROUND WX APPROX 200 MI FROM MIA S OF NAU. FO WAS FLYING THE LEG AND WE WERE GOING BTWN 2 CELLS BEING PAINTED ON THE RADAR. ANTI-ICE AND SEAT BELT SIGN WERE BOTH ON. WE WERE IN A HIGH LAYER OF CIRRUS CLOUDS AND HAD ALREADY FLOWN THROUGH WHAT APPEARED TO BE THE WORST PART OF THE WX AND WERE ABOUT TO BREAK OUT INTO THE CLR WHEN WE ENCOUNTERED SEVERE AIR TURB LASTING APPROX 10 SECONDS. AFTER GETTING THE ACFT BACK UNDER CTL; I CALLED TO THE BACK TO CHK THE CONDITION AND WAS INFORMED FLT ATTENDANT HAD SUSTAINED BACK AND NECK INJURIES. I THEN INFORMED ZMA OF THE SIT AND DECLARED A MEDICAL EMER REQUESTING CLRNC BACK TO MIA. I INSTRUCTED THE FLT ATTENDANT TO REQUEST WHETHER WE HAD ANY MEDICAL DOCTORS ON BOARD AND FOUND 2 TRAUMA NURSES. I ALSO CHKED THE CONDITION OF THE PAX AND WAS INFORMED THERE MAY BE SOME MINOR INJURIES. WE THEN RETURNED TO MIA WITHOUT FURTHER INCIDENCE EXCEPT FOR THE FACT THERE WERE NO GUIDEMEN TO MEET THE ACFT EVEN THOUGH DISPATCH ATC AND RAMP HAD ALL BEEN NOTIFIED.