I have been working as a parent volunteer for our girls' softball team. The coach has been doing some taping of the girls' knees who have pain during squatting. I notice it seems to help some girls right away. Others don't really seem to benefit. Why is that?

Taping has been used by many coaches, trainers, and therapists working with athletes who have ankle, knee, or shoulder pain. Taping usually stabilizes a joint and holds it in place. This takes pressure off the joint and nearby structures. It forces the muscles to respond more normally.

Studies definitely show a wide range of responses to taping. It would be very helpful if it were known who could benefit from taping rather than spending time trying out taping on a trial-and-error basis.

Pain during squatting may be caused by a problem called patellofemoral pain syndrome (PFPS). A recent study from Australia found two patient characteristics that may help predict which athletes with PFPS can benefit from knee taping.

The first is the patellar tilt test. The examiner glides the patella toward the outside of the knee, and then tries to lift the outer border of the patella up. In the normal knee, the patella should stay flat and should not lift up. Too much lift means the patella is very mobile and unstable.

The second is the angle of the tibia (lower leg bone). Bowing of the leg past five degrees seems to contribute to the problem of PFPS. Patients with these two positive tests often get immediate pain relief with taping.

The girls on your team who don't get any pain relief from this type of taping may have some other problem that needs to be identified. Some other form of treatment may work better for them.