This article is more than 5 years old. Information may no longer be current.
No differences in knee morphology for older patients with vs without patellofemoral pain
Click Here to Manage Email Alerts
Contradictory to current perceptions, older people with vs. without patellofemoral pain do not demonstrate differences in patellofemoral morphology on 3-D quantitative imaging analysis, according to findings.
Researchers identified two groups of patients enrolled in the Osteoarthritis Initiative database. One group had localized patellofemoral pain, pain on stairs based on the WOMAC pain subscale question and a tibiofemoral joint Kellgren-Lawrence (KL) grade of 0 in at least one knee. The control group had no self-reported pain in the patella region, an overall WOMAC score of 0, a numerical rating scale score of 0, KL grade of 0 and no previous surgery. Neither group had radiographic OA. Researchers converted 13 imaging features into 3-D equivalents and a measure of overall 3-D shape.
Researchers assessed 115 knees with patellofemoral pain (PFP) and 438 knees without PFP. They found that overall, there were no statistically significant disparities between patients with vs. without PFP for any of the 13 3-D features evaluated. In a sensitivity analysis, these findings persisted, with no statistically significant differences for any of the 3-D features.
In univariate models, no correlation was found between the individual 3-D features and PFP. Multivariable models showed that after combining 3-D imaging features, this lack of a significant association with PFP persisted. All odds ratios continued to be close to the value of 1, suggesting a lack of relationship to pain, after adjusting for gender.
The linear discriminant analysis found that an inability of the overall 3-D shape to significantly discriminate between the group with and without PFP, demonstrating a classification of 55.5%. Conversely, the overall 3-D shape demonstrated significant discrimination between men and women, with a classification of 90.6.
“Analyses of the overall 3-D shape in relation to gender validates these novel measures and suggests future PFP cohort analyses should be stratified for gender,” the researchers wrote. “Further work is needed to assess whether 3-D quantitative analysis can discriminate shape differences related to PFP in a younger population, more characteristic of PFP.” -By Jennifer Byrne
Disclosure: Bowes reports being an employee and shareholder of Imorphic Ltd., a wholly owned subsidiary of Stryker Corp.
Collapse
Drew BT, et. Rheumatology. 2017; https://doi.org/10.1093/rheumatology/kex329
Click Here to Manage Email Alerts