36 participants recruited aged between 18 to 50 years of age
Participants will be considered eligible for the study group if they have had two or more episodes of patellar dislocation or multiple episodes of subluxation with at least one of the following:
i. Positive patellar apprehension test ii. Tenderness along the medial retinaculum iii. Abnormal patellar tracking or position.
The study group will undergo gait analysis and electromyography before surgery and 6 months after surgery.
During surgery the study group will undergo intra-operative tracking and pressure measurements.

36 participants recruited aged between 18 to 50 years of age, matched for age and gender with the study group. Control participants should be healthy subjects with no history of knee injury or surgery.
The control group will undergo gait analysis and electromyography.

Patellar Dislocation

Participants will be asked to walk on an instrumented treadmill. The study group will undergo gait analysis before surgery and 6 months after surgery. The control group will undergo gait analysis at one visit only.

Gait analysis

Participants in the study group will undergo electromyography before and 6 months after surgery. Participants in the control group will undergo electromyography at one visit only

Electromyography

Participants in the study group will undergo intra-operative tracking and pressure measurements to see if corrective surgery to stabilise the patella improves tracking and pressure measurements

Intra-operative tracking and pressure measurements

St George's Hospital

Imperial College London

The Unstable Kneecap - the Impact of Anatomy on Function

Surgery for Patellofemoral Instability, is There Normal Gait

Graphical measurement of raw kinematic data to include joint moments at ankle, knee and hip comparing patients with patellar instability to normal controls

Graphical measurement of raw kinematic data to include joint moments at ankle, knee and hip comparing patients after surgery to correct patellar instability to normal controls

Measurement of ground reaction force of patients after surgery to correct patellar instability compared to normal controls

Graphical presentation of patellar movement in three dimensions measured intra-operatively during corrective surgery

Graphical presentation of patellar pressure in three dimensions measured intra-operatively during corrective surgery

Electromyographic (EMG) output in graphical form comparing patients with patellar instability to normal controls

Electromyographic (EMG) output in graphical form comparing patients before and after surgery

knee dislocation/דיסקינזיה

The Unstable Kneecap - the Impact of Anatomy on Function

המאגר השלם ביותר של צמחי מרפא המגובה על ידי המדע