Slow recovery of ROM post ACL - any help?

Have a 6 month old daughter hence sitting at the PC on a lovely summer's day.

However that is not the problem 'cos ALSO have a 25 year old social level sportsman/IT consultant; post-op ACL reconstruction (hamstring graft). Arrived 3/52 post-Sx with extremely antalgic-looking gait (due to ROM issues, not pain), lacking 25 deg ext (passively); only about 40 degrees of flexion (passive). Not braced post surgery, threw away his crutches (in order to work), given very little advice and chose to ignore most of the little he was told.

3/52 later - -5 extension (passive) -10 active; 50 flexion (active) ; 60 passive. No (minimal) visible swelling, strong quad contraction and good single leg proprioception within active range, 'good' gait, no patellar femoral probs. However, despite extensive mobs (accessory in prone etc), flexion mobs, ST work hamstring/politeus/gastrocs/scar and an extensive rehab programme - ROM is extremely poor for 6/52 post-op.

Extension (passive) appears limited by soft tissue (?- arthrofibrosis?); flexion (passive) by severe discomfit in the region of the medial portal scar - scar tissue ?/ infrapatellar branch of the saphenous nerve? (not positive on modified sidelying knee bend a la Butler and no change with L2-L4 unilateral lumbar mobs)

I am going to send him back to the surgeon asap but any ideas, comments, suggestions welcomed

cheers physioz