Will a meniscus injury disqualify me from joining the u.s. air force?

Probably not: It depends how the meniscus tear is affecting your function. Mri's often show signal changes that can be interpreted as a tear by the radiologist reading it. If you have localized joint pain, swelling, locking or giving way then you likely need arthroscopic surgery. I have had many people who have had knee or shoulder surgery rehab and joint the armed forces.

Not necessarily: Many meniscus injuries will heal without any deficit or symptoms. Depends on the location and degree of injury. Some will cause locking of the knee and severe pain and can happen in association with injury to ligaments while other meniscus injuries will be more minor and can heal without surgery, or possibly with relatively minor arthroscopic surgery.

NPQ status: Causes for rejection: a. Limitation of motion. An individual will be considered unacceptable if the joint ranges of motion are less that the measurements listed below. Knee (due to disease, injury): (a) full extension compared with contralateral. (b) flexion to 90 degrees. (1) loose or foreign bodies within the knee joint. Physical findings an unstable or internally deranged joint.