Eating up a cardinal plane.
Simple post, simple principle today. We found this case on the web, somewhere. Wish we could remember so we could give credit.
Looks like simple right leg length discrepancy but the point we wanted to make is that any time you deviate into a plane, you eat up length. In this case, the right knee is severely valgus and that has at least in part contributed to a shorter limb and unleveling of the pelvis. And, it is not uncommon that rotation axis are changed when frontal or sagittal planes are compromised. It is easy to see this on the x-rays, if the foot posturing isn’t at least noted, look at the spacing between the tibia and fibula . . . . rotational planes have changed as well. Is it from the femur or tibia? That is the topic of another day.
In the larger photo you will notice that even with the right foot lifted there is still a pelvis unleveling. How can that be, unless it was further unleveled that what we are seeing ? Well, just because you lift to fix doesn’t mean the lift will not enable further collapsing into the weakness and deformity. We have described this principle on the topic of EVA shoe foam deformation. When the foot presses the foam into the deformation, it leaves more room for possibly further and faster deformation loads (perhaps more so than had a new shoe been prescribed). So in some cases, more lift can allow more deformation. How far, well as in this photo, at least until the right knee slams into the left knee and stops further deformation.
So, seeing a plane deficit clues you into possible unleveling of the pelvis and abnormal joint loading responses. It should clue you into looking for another cardinal plane compromise as well. But make no mistake, just adding a lift doesn’t mean the deformation is remedied and not enabling further deformation. It is possible that you can make your client worse if you do not teach them how to find the appropriate motor patterns with the lift so they can learn to protect the parts. Often teaching these types of clients how to control their deformities (when and if possible) is where the gold lies, not in just leveling out the foundation.
One more “beating of the dead horse”, lift the whole foot, heel and forefoot with a sole lift when you are “lifting and leveling”. Lifting only the heel puts them into ankle plantar flexion and can often facilitated earlier and faster forefoot loading and even earlier knee flexion. Save the heel lift as a possible consideration when there are posterior compartment contractures or inflammation. Certainly we could have gone into functional and structural leg length discrepancies, but we have blogged excessively on that topic in the past. Go ahead and search our blog if you want more on those topics.
Take home point, “just because you lift, doesn’t mean you are truly lifting, you may enable the opposite”.
Shawn Allen, one of the gait guys