So a patient presents to your office with a recent history of a L total knee replacement 8 weeks ago AND a recent history of a resurgence of low back pain, supra iliac area on the L side. Hmmmm. Hope the flags went up for you too!

His global lumbar ROM’s were 70/90 flexion with low back discomfort at the lumbo sacral junction, 20/30 extension with lumbosacral discomfort, left lateral bending 10 degrees with increased pain (reproduction); right lateral bending 20 degrees with a pulling sensation on the right. Extension and axial compression of the lumbar spine in left lateral bending reproduced his pain.

Neurologically he had an absent patellar reflex on the left, with diminished sensation over the knee medially and laterally. Muscle strength 5/5 in LE; sl impaired balance in Left single leg standing. There was incomplete extension of the left knee, being at 5 degrees flexion (right side was zero).

He has a right sided leg length deficiency (or a left sided excess!) of 5 mm. Take a look at the tibial lengths in the 1st 3 pictures. See how the left is longer? In the next shot, do you see how the knee cannot completely extend? Can you imagine that the discrepancy would probably be larger if it did?

Now look at the x rays. We drew a line across from the non surgical leg to make things clearer.

Now, think about the mechanics of a longer leg. That leg will usually pronate more in an attempt to shorten the leg, and the opposite side will supinate to attempt to lengthen. Can you see how this would cause clockwise pelvic rotation (in addition to anterior pelvic rotation)? Can you see this patients in the view of the knees from the top? Do you understand that the lumbar spine has very limited rotation (about 5-10 degrees, with more movement superiorly (1)  ). Does it make sense that the increased range of motion could effect the disc and facet joints and increase the patients low back pain?

So, how do we fix it? Have you seen the movie “Gattica”? Hmmm….A bit extreme. How about a full length 3mm sole lift to start, along with specific joint manipulation to restore normal motion and some acupuncture to reduce inflammation? We say that is a good start.

The Gait Guys. Increasing your gait literacy with each and every post. If you liked this post, please send it to someone else for them to enjoy and learn. 

(1) Three-Dimensional In Vivo Measurement of Lumbar Spine Segmental Motion Ruth S. Ochia, PhD, Nozomu Inoue, MD, PhD, Susan M. Renner, MS, Eric P. Lorenz, MS, Tae-Hong Lim, PhD, Gunnar B. Andersson, J. MD, PhD, Howard S. An, MD Spine. 2006;31(15):2073-2078.