The below is a good explanation of Radamel's current situation I found in another forum, definitely worth baring in mind the next time this thread/forum bursts into hysteria...
"When training to correct imbalances you run the risk of injury to the newly activated muscles because they are doing work that they previously were not doing (shut down/misfiring). Aside from Rojo and Ander (and possibly Falcao) having injury issues that are contact related anything that is part of the muscular balance aspect will sort itself out as players get stronger. If you ignore the imbalances you will have a player functioning at a status quo or gradually deteriorating level until the imbalance contributes to a major non contact injury....like tearing your ACL when you are in open space and you plant to strike a ball or change direction.
Per all the hype in the media about Falcao.....it is pretty common to ice the knee for up to 24 months post status on an ACL reconstruction for a high demand athlete at this level, especially given the rapid return to training that he embarked upon. The people reporting the "shock" at this are talking nonsense, they clearly don't know anything about ligamentous injury/recon/repair, rehab protocol, or progression post status. There are various reasons as to why he is/might be swelling. He had major surgery that took one body part to replace another.....in the days of advanced surgical techniques, accelerated rehab, and PED's the world sees an ACL as a run of the mill bump in the road; I can assure it is anything but run of the mill. Post status you have to get your muscles balanced, achieve terminal extension (matching or very close to your contralateral side), deal with nerve damage, scar tissue, bone trauma, aches, pains, patella tracking, IT band tightness, and a host of other physical things that can set you back and cause swelling. You also have to deal with the mental aspect of trusting your knee to function again and getting over the fear of "will it tear again?" in your mind whenever you plant, pivot, or land on that leg. You worry that every ache means that your surgery was flawed and you'll never be the same. I don't care how mentally tough you are or how highly regarded the surgeon, you will doubt yourself and your reconstruction a lot more than you will believe in yourself for a long, long time.
Falcao actually had a slower return from his other ACL injury lay off because of consistent secondary issues related to muscular imbalances and frequent pulls/strains; this shouldn't be a shock to anyone that did their due diligence on him. He was most likely rushed back recently because he was hitting rehab milestones that include strength, plyometric, and endurance markers that are used to judge a "successful" reconstruction and he was motivated to say he was ok because of the World Cup. The issues with that situation are plentiful....the environment is controlled and the markers are arbitrary, especially to a top level athlete that can push their body through strength and pain barriers that most people can't handle, even more so when something like the World Cup is driving you on. I would imagine Falcao is is likely experiencing some of the standard post status issues with little injuries and swelling/aches/pains. It is major surgery and it hurts for a long time afterwards.
Unless the surgeon made a significant error in the tensioning or placement of Falco's graft, it is highly unlikely that he will have instability in the knee or malfunction that would cause a repeat injury under non-contact conditions. When you see players like Holden or Rossi blowing their knee a second time in training right upon their return it is usually down to some combination of: A) overly vertical graft placement/overly tensioned graft, B) Surgery too soon after injury (you need weeks to let the knee clam down after acute injury), C) Graft choice - Bone Patellar Bone is the gold standard, not hamstring or cadaver; quad tendon (which Falcao had on this one) has had recent success and mixes the Pros of hamstring (less site morbidity) and BPB (bone on bone healing for a graft plug), but it is less proven globally, D) Rushed rehab and return.
Only "B" occurred in Falcao's case. Immediate surgery seems to be the norm in Europe vs. America where it is usually 4-6 weeks post injury for surgery, unless you have an accompanying meniscal injury (bucket handle tear) that gives you a flexion contracture, then it is usually a 2 week wait. At this point, if his graft and knee are stable, he will most likely be ok in the long term. It is just a matter of the media laying off which will be hard because he's a high profile target and supporters/United being willing to wait for him to return to full stride. The latter might take the full season. Personally I am willing wait for that ROI."