Table 1.

Inclusion and Exclusion Criteria^a

Inclusion Criteria

1. Visual analog score rating of pain during activities of daily living during the previous week at a minimum of 3 cm on a 10-cm scale

2. Insidious onset of symptoms unrelated to trauma and persistent for at least 4 wk

3. Pain in the anterior knee associated with at least 3 of the following:

a. During or after activity

b. Prolonged sitting

c. Stair ascent or descent

d. Squatting

4. Pain with palpation of the patellar facets or pain during step down from a 20-cm box or during a double-legged squat

5. Recreationally active (≥30 min/d, 3–4 d/wk for the past 6 mo and exclusive of pain)

Exclusion Criteria

1. Meniscal or other intra-articular injury

2. Cruciate or collateral ligament laxity or tenderness

3. Patellar tendon, iliotibial band, or pes anserine tenderness

4. Positive patellar-apprehension sign

5. Osgood-Schlatter or Sinding-Larsen-Johansson syndrome

6. Evidence of effusion

7. Hip or lumbar referred pain

8. History of recurrent patellar subluxation or dislocation

9. History of surgery to the knee joint

10. Nonsteroidal anti-inflammatory drug or corticosteroid use within 24 hours before testing

11. History of head injury or vestibular disorder within the last 6 months

12. Pregnancy

^aAdapted from Boling et al.¹²