Over the counter (OTC) orthotics may be a cost effective way of addressing a patient who has knee OA and mild to moderate pronation. However, they are labeled by standard shoe sizing and may not be an option for those who require special sizing, patients with foot deformities or abnormal foot/ankle postures. These products typically break down faster than custom orthotics because they are often fabricated by materials of lesser quality.
Custom orthotics while more expensive may be a better option for someone who has a significant orthopedic issue. Today’s technology eliminates the need for a cast mold or crush box and replaces it with a digital scan of the patient’s foot. Custom orthotics are sized and designed to meet the patient’s unique and specific needs. They can be made of a variety of materials with varying densities and lengths. They also allow for modifications such as posting, wedges, etc. Lastly unlike over the counter orthotics they can be adjusted frequently by the clinician who dispensed them based on the patient’s feedback.
Medial posting (rearfoot varus posting) can correct for pronation at the subtalar joint which is common in the general population. Pronation can cause added stress to the medial joint line and can contribute to medial compartment osteoarthritis.
Lateral wedges are another option for the patient who has medial osteoarthritis. They reduce varus torque on the knee and help to take pressure off the medial compartment. They are not very beneficial however to patients with multi-compartmental OA, or lateral OA which is less common. It should be mentioned however that although they can decrease OA pain, there is no conclusive evidence that orthotics reduce the progression of OA, nor is there evidence that they are effective for treatment of lateral OA. (9,10)