Physical Therapy: Learning to Walk Again

I'm suffering from arthrogenic muscle inhibition (AMI), which is hypothesized to be due to the loss of neuromuscular innervation supplied by nerves running along side the ACL (ref). After all knee surgeries the muscles of the leg surrounding the surgery site are "stunned" and can take weeks to recover. In the meantime I've got an immobilizer on to keep me from buckling my swollen knee and undoing all the good work already done on it. My question to this hypothesis is that since I didn't really have an ACL to start with, what nerves were destroyed in the surgery?
My first session of "real" PT started today. I'd finally gotten so that I could lift my leg mostly under its own power as well as getting me to flex and extend my knee. My physical therapist took a look at my "walk" and explained the proper method for using a single crutch, opposite and simultaneous with the injured extremity. He assessed my knee flexibility, not quite straight and only able to flex it to 72° by myself and 86° with assistance. My right knee is a good inch longer in circumference, too.
I was given several new exercises as well as continued my old ones:

1. Kneecap Self Mobilizations (basically stretching the knee cap in the four cardinal directions to prevent adhesions from the patellar tendon graft) 2 sec hold x 5-10 reps, 2 sessions per day
   
2. Extension stretch (letting gravity flatten my knee with the foot elevated) 1-5 minutes, 3 sessions daily
   
3. Lying Knee Flexion (lying on your back trying to pull your foot to your butt) 1 second hold x 10 reps, 3 sessions per day
   
4. Quadriceps Set (squashing a towel flat with the posterior surface of the knee) 5 sec hold x 10 reps, 3 sessions per day
   
5. Leg Raise 10 sec hold x 10-20 reps, 2-3 sessions per day
   
6. Seated Knee Flexion (sit on a table flex the knee) 10 sec hold x 10 reps, 2-3 sessions per day