Knee surgeon specialising in ACL reconstruction, patella stabilisation, knee replacement, arthroscopy. Researching 3D quadriceps alignment. Opinions my own
Quadriceps Malalignment is the driver of patellofemoral joint imbalance. It leads to lateral patella osteoarthritis, patella dislocation, anterior knee pain and poor outcomes after knee replacement. It’s a new concept most doctors don’t know about. #knee https://t.co/9OvEqIPEYh
If we’re serious about understanding PFJ pathology, this needs to be part of the conversation.
I’ve put together a clear summary of the evidence, imaging methods, and concepts here:
https://t.co/9OvEqIPEYh
I’ll keep updating it as new data emerges.
We’ve been getting the patellofemoral joint wrong
🧵
Most models treat PFJ pathology as a bony alignment problem.
TT–TG. Trochlea. Q-angle.
But these don’t explain what we actually see clinically.
The primary driver is being missed:
Congenital variation in quadriceps alignment.
The only way to detect this is with imaging:
→ CT or MRI
→ Direct measurement of quadriceps muscle/tendon alignment
This is a new—and controversial—concept.
But it is measurable, reproducible, and increasingly supported data
Quadriceps alignment part 1 (Why the Q angle is wrong)
It is ridiculous that in this era of 3D imaging we still use the 2D Q angle as an indication of the force vector of the quads. https://t.co/vw7GzQrpah via @YouTube
The Q angle is wrong - a 2D line which ignores the 3/4 of the quadriceps attaching to the femur. When you measure in 3D quads alignment is much more variable and clinically relevant - maltracking, lateral patella OA, instability, TKR outcomes https://t.co/Brs4Kqf8Xf via @YouTube
@KSSTA Thanks KSSTA Journal
Patella maltracking is caused by mismatch between the alignment of the extensor mechanism (quadriceps) and the flexion axis of the knee. Femoral component external rotation alters the flexion axis of the knee to compensate and was shown to improve outcomes.
@Patelladoc Do you think that this disparity between the patella path and the bony anatomy may be due to a rotational malalignment of hte quadriceps? https://t.co/nDc61BcDEd
The way we have been measuring the alignment of the quadriceps mechanism (the Q angle) is wrong. It doesn’t detect quadriceps malalignment due to rotation of the quads muscle attachment laterally around the femoral shaft. https://t.co/mYvkAbLMR8 #knee#physiotherapy#Orthopedics