Patellofemoral Update
Patellofemoral Update
February 13, 2019
1 min read

Weight-bearing Merchant radiograph reliable for assessment of patellar tracking in TKA

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact

The weight bearing Merchant radiographic view compared with the routinely used standard radiographic view may offer additional information, is easy to perform and is reliable for the assessment of patellar tracking, according to a recently published study.

Researchers randomly selected 120 patients who were to undergo TKA to receive either an inset round, onlay round or onlay ova patellar implant with a single TKA prosthesis. At 6 months postoperatively, patients were assessed with both the non-weight bearing standard radiographic views and weight-bearing Merchant views. Improvements in KOOS, WOMAC and Kujala scores were associated with indicators of patellar tracking. Two readers evaluated radiographs for reliability assessment.

Results showed the weight bearing Merchant view, compared with the standard view, reduced the percentage of outliers of tracking indices. Investigators noted with the weight bearing Merchant view there was an increase in the lateral contact state. There was a constant and statistically significant correlation between the state of the lateral contact and the improvement in KOOS, WOMAC and Kujala scores. Good reliability and accepted variability were seen with all radiographic indices. – by Monica Jaramillo

Disclosures: The researchers report no relevant financial disclosures.