As a precaution in case of spring breakage, Citroen produce a spring catcher which is intended to catch the broken spring before it does any damage to the tyre. This was produced as a precaution for some C2's which had springs that rusted prematurely. Should a spring break the end coil could either force itself down between the spring mount and the tyre or the sharp edge could puncture the tyre. Luckily most (not all) spring breakages occur when the car is stationary and very cold.
Citroen part numbers are 5031.A5 for left-hand and 5031.A4 for right-hand Spring Catchers - always buy a pair!
You may also need four bolts 6922.H3 and four nuts 6936.C9 (though they were included with my catchers)
They were fitted to the Citroen C2 and C3 models as well as the Peugeot Partner
The spring catcher comes in two parts which are bolted together around the strut to create a substantial cup to catch the broken ends. Put the bolts in from the back or conflict makes it impossible to get sockets or ring spanners onto the nuts so you have to use open-enders as here.
The smaller part has a oblong cut-out which is first fitted from the rear and over the roll bar mounting lug. The larger part is then bolted to it - the assembly is quite rigid once the bolts are tightened.
I checked the spring pans - the one on my wife's car (which had the broken spring) had much surface rust evident (20,000 miles). Mine showed no rust at 35,000 miles. So past history is important.
All the new springs had the plastic sleeves already fitted to the springs and I have now covered the lower coils on all four springs with Waxoyl as a precaution (March 2012).
We have been able to go back to driving our 1007's normally and our new springs have no corrosion, are protected by extra paint and waxoyl and if the worst happens have the cups to contain broken ends of the spring.