Knee problems such as instability of the kneecap and arthritis can be telltale signs that it’s time for surgery.
But they’re not the only ones.
A new study suggests that focal lesions of the cartilage that cushions the kneecap, or patella, and of the trochlea, the groove where the patella rests, are just as important and can have similar causes. Understanding how these lesions are related to knee alignment and morphology could help clinicians develop more tailored and durable treatments.
Researchers reached that conclusion after comparing the knee anatomy of 135 patients with focal patellofemoral cartilage lesions, but no arthritis, to that of 100 patients with normal cartilage.
Using M-R-I, they assessed features including patellar morphology, trochlear morphology, patellar malalignment, and the quadriceps vector.
Patients with patellofemoral lesions showed greater trochlear dysplasia and patellar malalignment than those in the control group. Trochlear dysplasia, defined as an unusually shallow trochlear groove, was associated with the highest increased risk of patellofemoral lesions—followed by a misaligned patella, one that is tilted and alta. Those factors could be the precursors of premature degeneration of cartilage in the knee.
The findings suggest that when it comes to choosing the best course of action for knee cartilage repair, there is no one-size-fits-all solution. The appropriate risk factors should be critically assessed, and treatment of cartilage lesions should be patient- and knee-specific. Additional surgery, such as reshaping the trochlear groove or realigning the patellar tendon, can then be pursued to address risk factors when needed.
The authors of the study do note a few limitations of their work. For one, the control group was not a completely “normal” cohort, as not all of those patients were free of knee issues. Additionally, results were obtained from a single patient population and may not apply to the general public.
Still, the results are highly instructive. For patients with cartilage lesions, treating their comorbidities could help clinicians better improve knee function and patient quality of life.