Patella alta and patella baja seen as predisposing factors for chondromalacia
Click Here to Manage Email Alerts
Patella alta and patella baja are predisposing factors for early onset chondromalacia, according to published results.
In the study, MRIs were taken for 133 patients (aged 18 to 40 years) with advanced chondromalacia (grades 3 and 4) and a control group with the same number of participants and a similar age.
“The MRI sagittal view with the greatest patellar length was used to obtain a patellar height measurement for the [Insall-Salvati] IS index,” the authors wrote in the study. “For the remaining three indices – modied Insall-Salvati (mIS), Caton-Deschamps (CD) and Blackburne-Pell (BP) – a sagittal view with the greatest patellar articular surface was used,” the authors added.
Patella alta and patella baja were found to predispose patients to chondromalacia, the authors wrote. The rarity of patella baja may explain why it is not often mentioned as a predisposition, they added.
“The modified Insall-Salvati index ratio was the best patella alta indicator that showed chondral status, more than patellar placement, and was more concordant with the other indices,” the authors concluded.
Perspective
Back to Top
Michael J. Medvecky, MD
The study by Ozel demonstrates a statistical correlation between patella chondromalacia and the extremes of patellar height (patella alta and patella baja). The study cohort included only patients between the ages of 18 and 40 years with grade 3 or 4 Outerbridge chondral changes with a comparison to matched age groups without patella chondromalacia.
It adds to the body of literature demonstrating the potential role of patellar positioning on the development of patellofemoral chondral changes. Important information that we still need guidance on is the relative contribution of patellar height on the multifactorial effect of patellofemoral geometry. The static nature of this information in the fully extended position makes it challenging to consider how we incorporate this single measurement into our treatment algorithm. From the data supplied, we are unable to provide neither any correlation of patellar height to the rate or onset of patellar chondral changes nor the degree of extensor mechanism malalignment in the coronal plane.
The goal of restoring “normal” patellofemoral height for the sake of improved patellofemoral stability needs to be weighed with the potential for iatrogenic distortion of patellofemoral contact pressure and the aggravation of preexisting patellofemoral arthritic pain, if a distalization procedure is performed.
Ozel is commended on his contribution to the patellofemoral literature with the goal of improving patient care and surgical management of these technically and clinically challenging scenarios.
Collapse
Read more about
Click Here to Manage Email Alerts