Description
Quadriceps tendon alignment (QTA) is highly variable in the normal population. The coronal alignment of the quadriceps tendon varies from 7 degrees valgus to 14 degrees varus. We developed three techniques for accurately measuring the alignment of the quadriceps tendon. We measured normal values in 110 scans. QTA was not linked to any other bony alignment in the lower limb. We then looked for clinical relevance by measuring the QTA in a group of patients with severe lateral patella osteoarthritis (LFPFJOA). The LFPFJOA group had greater quadriceps tendon lateral malalignment than the normal control group. QTA was the predominant deformity associated with LFPFJOA.
Patella maltracking caused by quadriceps malalignment is clinically relevant for patella instability and knee arthroplasty surgery. In patients with patella maltracking the recreation of their native anatomy with personalised alignment techniques such as kinematic and functional alignment may recreate the preexisting maltracking. By identifying these patients preoperatively we may be able to adjust our alignment techniques to prioritise the realignment of the extensor mechanism.
