Patellar subluxation is a common disorder that may cause patellofemoral pain syndrome. The efficiency of patellar taping in the treatment of patellofemoral pain syndrome has been reported good outcomes in most patients. However, some studies reported less effective in patients with higher body mass index, larger lateral patellofemoral angle, and smaller Q angle. The investigators hypothesized that femoral internal rotation is a negative factor to the patellar taping. The investigators enroll consecutive 100 patients with anterior knee pain and radiographic evidence of patellar subluxation. The investigators determine femoral rotation via physical examination. The visual analogue scale was evaluate to compare the result between the those with and without femoral internal rotation.

Consecutive 100 patients with anterior knee pain and compatible with inclusion criteria. Before treatment, an independent physiotherapist evaluates whether femoral internal rotation or not via physical therapy, and another studying nurse records the visual analog scale and measures Q angle. After evaluation, McConnell taping is applied to these patients. Two weeks later, outcomes are recorded including visual analog scale, satisfactory, and complication. The outcomes are compared between those with and without femoral internal rotation.

Inclusion Criteria:

• anterior knee pain
• radiographic evidence of patellar subluxation

Exclusion Criteria:

• history of patellar dislocation
• osteoarthritis of ipsilateral knee
• pregnancy
• history of knee injury
• BMI > 35
• allergy to taping

100 patients