Unilateral increased tibial varum; one reason why...

Take a look at this gent in the picture. Do you notice anything peculiar? Pick a point and start either moving from above down or from the ground up.

From the ground up, the first thing you may notice is that he has a hallux abducto valgus on the right side. This could be for any number of reasons and what it actually tells you is that he is unable to anchor his first ray to the ground and have appropriate function of the adductor hallucis. Your job, during the examination process, is to sort that out.

The second thing you may notice is that he has more midfoot collapse on this same side. You would think that with that much midfoot collapse he would get his first ray to the ground but that’s obviously not the case.

Moving up from there, you may have noticed that he has significantly more tibial varum on the left-hand side. Tibial varum should be about 4-6 degrees and is largely a function of in utero positioning although diseases like osteomalacia and rickets can increase it though this is often more bilaterally symmetrical.

You need to be aware increased tibial varum means that the foot, particularly the forefoot, needs to pronate a greater degree to create a stable foot tripod on the ground. You need to ensure during the examination process that adequate range of motion in the forefoot and 1st ray are available.

You may have noticed that there is prominence of the left medial head of the gastroc which is most likely a combination of positioning as well as increased mechanical advantage secondary to the varum.

Hopefully you noticed that the knees are (relatively) in the sagittal plane and that there’s an increase progression angle on the left-hand side. If you drop a plumbline from the tibial tuberosity you’ll see the falls medial to the second metatarsal shaft indicating external tibial torsion in the lower extremity.

The unilateral increased tibial varum on the left-hand side is secondary to an anatomical leg length discrepancy where the right tibia is shorter. This has been long-standing and in compensation, the left tibia has “bowed“ to compensate for the difference, In an attempt to shorten the left leg.

Dr Ivo Waerlop, one of The Gait Guys

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#tibialvarum #leglengthdiscrepancy #lld #bowedlegs #pronation

The Mighty Quadratus: Part 2  The Quadratus and Gait

Acting unilaterally without the ipsilateral foot fixed on the ground, it can raise the ilia on the side of contraction (as in a pull up or side bend on a Roman chair). The quadratus lumborum was more active than other muscles during isometric side support postures where the body is held horizontally almost parallel to the floor as the subjects supported themselves on one elbow on the floor together with both feet. 

It is active during single limb support during stance phase of gait on the contralateral side (along with the external oblique) to elevate the ilium. This is coupled with the ipsilateral anterior fibers of the gluteus medius and minimus pulling the iliac crest toward the stable femur.

Sahrmann states “the QL is optimally situated to provide control of lateral flexion to the opposite side via its eccentric contraction to provide control of the return from lateral flexion via its concentric contraction. The muscle is also positioned to play a role in the rotation that occurs between the pelvis and spine during walking”. This makes you really think about the interplay of this muscle, and another stance phase stabilizer, the psoas major, which attaches opposite the QL on the anterior aspect of the vertebral body, IN FRONT of the transverse process.

Acting bilaterally, it extends the lumbar spine, deepening the lordosis and acting to limit anterior shear of the vertebral bodies.

It is able to stabilize the 12^th rib during forced expiration, thus acting as an accessory muscle of respiration. This fixation is important when we need to superimpose pelvic movements upon it. Furthermore, it increased activation in response to increasing compression in static upright standing postures.

Bottom Line?:

Think of the QL, especially during gait abnormalities or recalcitrant low back pain. The more it is stressed, the more it is activated. If someone had mild weakness of the stance leg gluteus medius, it may be called into play to pick up some of the slack. Expect to see increased activity paraspinally, with particular attention paid to the 12 rib attachments.

In our flexor dominant society, the QL may play a role in generating unilateral shear forces on the lumbar spine (along with the ipsilateral psoas), especially in individuals with poor ankle rocker or decreased hip extension.

The QL: it’s not only for breakfast anymore…..

We still are…The Gait guys