Patellar malalignment

Patellar malalignment is a general term pertaining to any abnormality of the position or tracking of the patella.

Malalignment is a very important diagnosis to make because malalignment of the kneecap and the surrounding tissues has the potential to cause pain and/or instability. It is a diagnosis that is frequently missed.

Now malalignment encompasses a number of conditions. If I am the patient and the surgeon says that I have malalignment then I would want to know exactly what he or she means by that term. If the surgeon says you have malalignment that means that he or she at least has some idea of what might be causing causing the pain.

The surgeon must feel that the patella is either tilted, meaning that the lateral side or the outside part is down, the other side is up - like a beret rather than a hat - or the surgeon thinks that there is an increased q-angle, which means that the tibial tuberosity is not positioned properly, and or the patella is riding too high in the groove . Or any combination thereof. So that is already a much more specific diagnosis than say ‘chondromalacia’. 

Examining the patella for alignment and tilt -

  • With regards to malalignment and the examination, it is important for the orthopaedist to begin examining the patient when the patient is standing up. One error is to zoom in on the knee, and a complex rotational malalignment of the leg will be missed if the person is examined in say the lying-down position and the surgeon zooms in right on the knee.
  • After examining the patient’s standing posture, the next thing is to examine the patient walking. There the surgeon may appreciate that the patient has very flat feet or high arches which can impact the knee.
  • Following that, the surgeon examines the patient in a sitting position and asks the patient to straighten the knee and bend the knee. At which point the surgeon – before he has even touched the patient – will see if the kneecap is tracking normally.
  • Finally the surgeon asks the patient to lie down, at which point he may start palpating the knee and again ask the patient to bend the knee back and forth. He can examine the position of the tibial tuberosity, judge the q-angle and so forth.

So that in a nutshell would be the sequence. With the patient lying down obviously there are many other things to check for - the tilting of the kneecap and of course there are other things in the knee that need to be examined.

doctor
Confident?
If the surgeon says “Well, I think your kneecap is tilted. Look! When I touch this quarter it is down, when I touch this quarter it is up and look on the X-ray, and look on the CAT-scan, and look on the MRI – you can see that the kneecap is tilted” – then that sounds like you at least have the right diagnosis. If the surgeon is not able to show what he or she means by malalignment and seems to be just using that as a general term the way he might have said ‘chondromalacia’, then I would be a little bit concerned.

 

Author

Dr Ronald Grelsamer

Knee Surgeon

Dr Ronald P. Grelsamer, M.D., board certified by the American Board of Orthopaedic Surgery in 1987, is associate professor of orthopaedics at Mount Sinai ...read more

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