Every time the foot strikes the ground, force travels from the ground up and from the hip down as we move. All of this needs to be distributed to the hip, knee, and the ankle.
Well the knee is the middle man in this entire scenario.
If the hip gets too far ahead of the knee during the swing phase, and stays ahead during landing, the weight of your body would be distributed in a more forward fashion. This places stress on knee joint itself, and could potentially lead to injuries such as patella tendonitis.
If the knee is too straight on landing and the hip stays too far behind, the knee won’t be able to get ahead of the ankle, causing a more locked knee position.
Patella tendonitis can also occur from a diminished strength/tissue tolerance in the quads. If the quads can’t tolerate the stress of repetitive motions, then the patella tendon can be at risk for increased strain.
Another way the knee can be stressed would be from the rotational ability of the hip itself (not just being forward or backward).
As the femur rotates one way, the tibia rotates in the opposite direction, relative to the femur.
These two bones meeting are what comprise the knee joint.
As the knee bends, the femur needs to be able to rotate outwards as the tibia rotates inwards (as the foot strikes the ground and the knee gets ahead of the ankle this tibia rotation occurs).
By having decreased rotation of the femur, the knee may get stuck in limited ranges during the gait cycle, forcing compensations to occur and increased strain to the joint.
If you go back to the last post on ankle stability, you will see that we suggested a front foot elevated split squat to help with knee control over the ankle.
This same exercise can help improve hip control to allow the natural rotation that occurs with knee flexion and extension.
Another way would be to perform a step-up from varying heights to control the phases of knee flexion and extension, while the hip absorbs most of the weight.
Just like we stated before, doing controlled exercises is step one, but you need to prepare for higher rates of force loading to increase tissue tolerance and be more adaptable to continuous movements like running.
Not only will this help with knee joint position and control, but if you have tissue tolerance issue that caused patella strains, establishing quad strength and increasing the speed it is loaded will also help with improving overall muscle tissue tolerance.
Some easy exercises to implement in the training program for increased rate loading would be split squats to a quick drop.
You would start in the top of a split squat stance and then drop to the bottom position quickly while stopping and holding in a controlled fashion.
Another exercise would be to perform a depth jump, focusing on the landing only from 2 legs to 1-leg starting with a low box of 6”.
As you can see issues at the knee can be similar to the reasons why the ankle may be in trouble as well. It all just depends where the compensations occur.
If you still have trouble figuring out how to solve your knee problem, write a comment below or email me at email@example.com and I will be more than happy to answer it.
Dr. Peter Dionisopoulos is the owner and founder of Dynamic Performance & Rehab. He has a Doctorate in Physical Therapy and enjoys to help active adults maintain their lifestyle and provide natural solutions to their pain.