hamper
obstruct
impede
inhibit
retard
balk
prevent
thwart
foil
curb
delay
arrest
interfere with
set back
slow down
hobble
hold back
hold up
stop
halt
restrict
restrain
constrain
block
check
curtail
frustrate
cramp
handicap
cripple
hamstring
stymie
throw a wrench in the works