Six months after an ACL repair is about the time most people start to see a return to more normal function. Of course, this depends on the patient’s age, overall health, and physical condition.
You should be seeing a gradual improvement in strength and motion. If not, you may have left out an important part of the rehab process. A physical therapist can help you sort this out.
The numbness is not uncommon. Almost all patients have some amount of numbness. This is because the nerve below the kneecap isn’t in the same place for everyone. There’s great variation in the location of the branches off the main nerve. In order to complete the surgery, doctors must cut through this area.
The loss of sensation is most likely going to be permanent. After 18 months, any changes in sensation are probably permanent. This damage doesn’t affect the function of your knee. It’s just annoying to many people.