There will probably be someone replying with a better grasp of MRI terms then me but here's my thought:
ACL is abnormal with upper distortion of the proximal odema??
The Anterior Cruciate is damaged - maybe a tear maybe a rupture. Odema is fluid swelling, proximal means next to. So I would read it as swelling around the ACL - possible tear/rupture of ACL - difficult to determine due to swelling. I fit is ruptured he may need an ACL reconstruction.
Damage to the free edge of the middle 3rd meniscus
Meniscus damage 50% of ACL damages have also meniscus damage. Menisci are cartilaginous elements within the knee joint which serve to protect the ends of the bones from rubbing on each other and to effectively deepen the tibial sockets into which the femur attaches. They also play a role in shock absorption. There are two menisci in each knee, the medial meniscus and the lateral meniscus. Either or both may be cracked, or torn, when the knee is forcefully rotated and/or bent. A damage to the menisus can require remedial surgery depending on the severity. In very bad cases parts are removed.
Damage to the weight bearing surface of the lateral femoral condyle
Thats the lower part of the femure, it could be bruised, dented or in worst case you may have a fracture.
Damage to the posterior aspect of the lateral tibial plateau.
Thats the platform on top of the tibia, thats the larger of the two lower bones (long ones) in the calf. Same kind of damage as above.
You should post this in the Cruciate ligament section of the bulletin board. There are more people with experience in this there.
I should think this MRI will lead to a meeting with an Orthopedic Surgeon. At this point you should read up on the construction of the knee and read up on damages to the ACL. You can find information on this on this site. The Cruciate Ligament part of the forum is very helpful. Finally look carefully into what the physiotherapy Leslie Hall says on this site abouth ACLs
Good luck,
Annika (8 weeks post op on a ruptured ACL)