Can changing your walk help knee arthritis? The foot bone is connected to the knee bone, however, the modern 90 second orthopedic exam for a knee problem almost never includes an examination of the foot. Despite this oversight, a new study shows that how your foot hits the ground can dramatically change the forces at the knee. In particular, placing more pressure on the inside of the foot reduces pressure on the inside of the knee.
The fact that the musculoskeletal system is a connected machine with specialized areas has been lost in Orthopedic care. Instead, we have specialists for the knee, ankle, shoulder, spine, etc… If all of these parts had nothing to do with each other and didn’t impact each other, then this would make sense. However, if they’re all connected and one impacts how the other works, then this hyper-specialization is a bad idea that can only hurt patients. Case in point is a biomechanics research article that was just published that shows just how much the foot and knee are connected.
The new research looked at how forces in the inside or outside compartment of the knee were altered when the pressure on the inside or outside of the foot was changed. Four subjects were asked to walk on a treadmill and either place pressure on the inside or outside of the foot. When pressure was on the inside of the foot, the inside compartment of the knee had 18% less pressure. The researchers noted that since most patients have medial (inside) knee arthritis, then simple modifications of the way they walk may make a big difference in reducing loading on the painful area.
The upshot? The foot bone is connected to the knee bone and what happens at one area impacts the other. For example, I often see patients who wear the outside of their shoes due to low level low back issues. Many of these patients end up getting bunions in the big toe, as the tendon that extends the toe gets pulled to the outside and the joint pushes out to the inside. These same patients also often develop arthritis on the inside of the knee. Can these patients make their knee and their foot better simply by consciously walking more on the inside of the foot?