Synonyms: Patellofemoral grind test, Patella hold test, Zohler’s sign
Tests for: Patellofemoral dysfunction
Patient position: Lying down with knees extended and relaxed (heels on table)
Technique:
1. Place the webspace of thumb on the upper pole of patella and push it inferiorly.
2. Ask the patient to contract his/her quadriceps muscle.
Interpretation:
- Positive test: Retro-patellar pain and patient cannot hold the contraction
- Negative test: No pain and patient can hold the contraction
2 school of thoughts:
1st thought: The examiner can achieve a positive test on anyone if sufficient pressure is applied to the patella. Hence, the test must be repeated several times, increasing the pressure each time and comparing the results with those of the unaffected side. To test different parts of the patella, the knee should be tested in 30, 60 and 90 degrees of flexion besides full extension.1
2nd thought: Since, it is a painful test, it should be performed only once and at the end of the examination.2