FLOATING (BELLOTABLE) PATELLA OR PATELLA TAP TEST

​• Test positioning

The client lies supine with both knees fully extended.

The therapist stands with the proximal hand over the suprapatellar pouch and the distal hand (thumb or first two fingers) over the patella.

​• Action

Compress the suprapatellar pouch with the proximal hand, then compress the patella into the femur.

​• Positive finding

Downward movement of the patella followed by a rebound will give the appearance of a floating or ballotable patella and is indicative of moderate to severe joint effusion.

​• Special considerations & comments

If a ballotable patella is detemined, the therapist should take girth measurements at the supra-, mid-, and infrapatellar regions and compare them bilaterally to more accurately assess the severIty/degree of effusion.

Additionally, the therapist must not mistake prepatellar bursitis as a joint effusion.

The former will present as a "raw egg" over the patella, but no downward patellar movement will be present.

Occasionally, concomitant joint effusion and prepatellar bursitis will be present and the therapist will therefore be challenged to make the proper assessment.