Gonarthrosis

Positive diagnosis:

Gonarthrosis is deformations are visible in advanced knee osteoarthritis: flexion, big bulging knee.

If patellofemoral osteoarthritis, pain radiates down and it is felt especially when descending stairs, prolonged squatting or sitting.

The pain woke up during friction of the ball against the trochlea (sign of the plane), the frustrated leg extension, blocking the ascension of the patella during quadriceps contraction (sign Zohlen).

Front knee in extension and 30 ° flexion (schuss); profile by extension and patellofemoral parade (= axial view at 30 ° flexion)

At a patellofemoral reached the pinch is usually outside with a patellar osteophytes external.

NB:

* This is the most common site of osteoarthritis. The involvement of the external tibiofemoral compartment is the most common (more than 50% of cases)

* It typically occurs in women over 40 years and is readily bilateral.

* Mechanical Osteoarthritis due to deformation of the mechanical axis of the lower limb, either varus (internal tibiofemoral osteoarthritis), self valgus knee (tibiofemoral osteoarthritis