Does degree of trochlear dysplasia and position of femoral tunnel influence outcome after medial patellofemoral ligament reconstruction?

Background: The medial patellofemoral ligament (MPFL) is the main restraining force against lateral patellar displacement. It is disrupted after patellar subluxation or dislocation. Reconstruction of the MPFL is frequently performed when nonoperative management fails and the patient experiences recurrent patellar dislocation.

Knee joint functional range of movement prior to and following total knee arthroplasty measured using flexible electrogoniometry.

The functional ranges of movement of the knee were investigated in a group of patients with knee osteoarthritis (n = 42, mean age 70 years) before, 4 months and at 18-24 months after total knee arthroplasty and then compared with age matched normal subjects (n = 20, mean age 67 years). Flexible electrogoniometry was used to record the maximum flexion-extension angle, the minimum flexion-extension angle and flexion-extension excursions of both knees during eleven functional activities along with the active and passive knee joint range of motion measured using a manual goniometer. Over the eleven functional activities the patients pre-operatively exhibited 28% less knee joint excursion than normal age matched subjects.