Inclusion criteria |
 • Aged 18–40 years |
 • Reported insidious (non-traumatic) onset of anterior or retropatellar knee pain |
 • Pain on two or more of the following activities: prolonged sitting, kneeling, squatting, running, patella palpation, hopping, stair walking, stepping down or isometric quadriceps contraction |
 • Peak hip abduction torque values [33]: Females [18–29 years] ≤ 94.1 Nm; Females [30–39 years] ≤ 75.8 Nm; Males [18–29 years] ≤ 144.1 Nm; Males [30–39 years] ≤ 139 Nm |
Exclusion criteria |
 • Presence of inflammatory arthritis; knee pain referred from the hip or lumbar spine; any history of significant knee surgery; other causes of knee pain such as, but not restricted to: meniscal pathologies, quadriceps tendon injuries, patella tendinopathy, tibial tubercle apophysitis; bursitis |
 • Received any treatment within the last 3 months including physiotherapy, podiatry etc. |