Most people are familiar with the Ottawa Ankle Rules, but there are also Ottawa Knee and Foot rules. The Ottawa rules help to limit the number of x-rays you may need in patients that present with ankle, foot or knee pain after an injury.
The Ottawa Ankle Rule
An ankle x-ray is only needed if there pain in the mallelolar area and any of the following:
Bone tenderness at the posterior tip of the base of the lateral mallelous
Bone tenderness at the posterior tip of the base of the medial mallelous
Inability to weight bear immediately and in the Emergency Department
The Ottawa Foot Rule
A foot x-ray is only needed if there is pain in the midfoot and any of the following:
Bone tenderness at the base of the 5th metatarsal
Bone tenderness over the navicular
Inability to weight bear immediately and in the Emergency Department
The Ottawa Knee Rule
A knee x-ray is only needed for knee injury patients when they have any of the following:
Age 55 or over
Isolated tenderness of the patella (no bone tenderness of the knee other than the patella)
Tenderness at the head of the fibula
Inability to flex to 90 degrees
Inability to weight bear both immediately and in the Emergency Department (4 steps - unable to transfer weight twice onto each lower limb regardless of limping).
