in order of lightness(putting length in to perspective)
189 LL2: about 9.2lbs apparently, my scale is off but said 9.4
190 Ruby: 9.2lbs a pair, will probably feel a lot like you Maden's, but much lighter, stiffer and better in pow. 188 Rubys are 9/pair, but why would you want the softer less charging version of the 190?
185(183..)JJ 09: 9.5lbs a pair
185 ARG: 10 lbs a pair or just under(09), and will ski even lighter.
Those are what came to mind right away, did you want a lighter Maden replacement(Rubys, Tahoes, Coombas are all lighter and similar) or a more "fun shape"?
Respectfully. May I suggest you ask your Dr what he meant by a light ski. Is he / she a skier ?
The actual weight of a ski is only experienced when both u and the ski are air airborne, or if is hanging off your leg on a chair without foot rests. When u are skiing the ski is on the snow and u r on top of it. So perhaps the Dr meant get a soft ski or a not to aggressive ski. Like sort of take it easy ski. A slower easy turn ski.
I admit I have no idea of your particular situation, but I wouldn't want you to get something with out the due diligence. The Dr may have meant a ski that is easy to initiate a turn so as not to strain the repaired tissue. So maybe no stiff, big radius hi speed skis. Maybe Salomon Guns (2008-2009) or something a little noodley. Maybe an all-day long kinda ski vs. an all-out couple runs only ski. U may hate them if u were an aggresiive skier. Sometimes these skis are for the "finese skier & style " vs. muscle and strength.
I did rehab for my knees with a ski specialist, and they said gradually over time, bring back your strength and no fast moves. It was the pressure I was exerting not the weight of the skis.
If it is weight, it would be the weight of the ski boot, the binding and the ski that would be trouble for you. Hoping the best for u.