Is a vertical talus completely rigid?

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Hi all, I'm a fairly new user and have a query in the paediatrics field?

does a vertical talus always show up initially as a rigid flatfoot?

I have an 11-year old boy with unremarkable madical history, Father has "flat feet" he has one of the worst CPVP foot type I've seen, there is massive saggital plane movement on weightbearing which virtually forms a rocker bottom foot, with both heels approximately 0.25cm off of the floor. There is no equinus at the ankle, and the foot is mobile. When the young lad stands on tip toe there is a small improvement in arch height but nothing too dramatic. There is hypermobility at elbows, and wrists but nowhere else, there is marked tibial varum both legs - which I guess is adding to the deformity. Initially mum brought him in to me because of tired/painful legs and painfull feet. I have given supportive footwear advice and issued a simple insole with deep heel cup and mid foot saddle - which has improved the symptoms but there is still occasional pain evident. Should I be checking for a vertical talus even though the foot is'nt completely rigid?

regards

Marc

 

Marc,
I recently did a consultation on a 12 y.o male with what sounds like a similar foot functionally (see photos). He has significant pronation on weightbearing. His AP film demonstrates talar adduction and plantarflexion with pronounced abduction of the navicular on talar head. Some would call this a skew foot. Of interest is the fact that his heels are not everted since most of the compensation has occurred due to talar adduction and due to sagittal plane compensation in the forefoot and rearfoot.

If your patient is similar, then I would highly recommend getting him into some functional orthoses to reduce the subluxing forces that are acting on the foot.

Respectfully,
Jeff
www.root-lab.com

 

Marc, it is possible your patient may have an ankle joint restriction but it could be masked in the sagittal plane due to dorsiflexion of forefoot on the rearfoot. My guess is that you probably are dealing with some degree of equinus. Look at the relative range of dorsiflexion of the rearfoot to the tibia in addition to the range of dorsiflexion of the foot as a whole. He may have a low calcaneal inclination angle like the child I showed. This can mask equinus.

Respectfully,
Jeff
www.root-lab.com

 

Thanks for the reply, I'll check when I next see the pt in about two weeks. If there is a low calcaneal inclination angle, what would you suggest for a treatment option? The mid foot saddle I have used is providing mid foot support and reducing plantarflexion of the calcaneous, Is there any way of reducing the inclination angle?

Regards

Marc

 

This is a case where I would probably correct the heel inverted (4 to 6 degrees?), use no medial arch fill, a wide arch profile, a medial heel skive of 6mm, a medial post flare, and a 25 medial, 20 lateral heel cup. The question is, how much of this deformity is congenital and how much is acquired? Why dose a foot develop like this, muscle weakness, ligamentous laxity, or what? If the patient could tolerate it, you could probably make a good argument for slightly adducting and plantarflexing the forefoot on the rearfoot during casting, in an effort to promote restoration of the medial and lateral longitudinal arches. A child like this should be encouraged to wear his orthoses at all times during weightbearing activity. While it is unlikely that we can improve (increase) the calcaneal inclination angle much, if at all, I do believe we can improve the position of the talus and the navicular. We need to catch these feet early before this level of subluxation can occur.

Also note the long 1st metatarsal, B/L. Could this condition be secondary to functional hallux limitus in conjunction with ligamentous laxity?

Respectfully,
Jeff
www.root-lab.com

 

I'm just wondering if you have x-ray'd this young man? My experience is limited with a vertical talus but those I have seen you know very early on in their lives. It is a child with a true rocker bottom foot with a posterior bulge. Often with some plantar weight bearing on the head of the talus.

While there can appears not to be an equinus with any child, for those with extreme ligamentous laxity, it can be difficult to measure, as what are you pushing back and gaining dorsiflexion at? The ankle or the forefoot? I know it sounds obvious but sometimes it is a tad subtle to see.

I think Jeff provided an excellent example of an extremely hypermobile flat foot. I have however seen very similar feet in kids that have CP, DCD and a few other genetic conditions so you need to be on your guard the foot position is there just because those ligaments are too lax and or bone position rather than a high tone gastroc or a foot seeking additional sensory input/slap for feedback.

 

Thanks for that Jeff I have only just managed to open the pictures that you attatched, basically the Childs feet that I am talking about are pretty much identical to the ones pictured?

I'll see him in a couple of weeks and do some more checks. Thanks again for your imput - much appreciated

Regards Marc

 

Marc:

If a pediatric flatfoot is "mobile" as you say, then it really isn't a "vertical talus" deformity. Vertical talus deformity basically involves dislocation of the navicular from its normal articulation on the distal talar head to a dislocated position on the dorsal aspect of the talar neck. Because of this abnormal TN joint position, the subtalar-midtarsal joint complex will not move much if any and these uncommon deformities require surgery. In other words, no, you don't need to check for a vertical talus if the foot isn't rigid.

If the pediatric flatfoot is "mobile", which is by far the most common type of pediatric flatfoot deformity, then it can be treated but would not be called a "vertical talus deformity". In the chapter I coauthored with Don Green, DPM, back 17 years ago, we called this foot a "pes valgus deformity" but it may also be called a pediatric flexible flatfoot deformity (Kirby KA, Green DR: Evaluation and Nonoperative Management of Pes Valgus, pp. 295-327, in DeValentine, S.(ed), Foot and Ankle Disorders in Children. Churchill-Livingstone, New York, 1992). I am attaching our chapter at the end of this post since the book is now out of print and unavailable except in libraries and personal collections. You would probably benefit from reading the chapter over thoroughly since much of what you ask about these feet is covered in the chapter. I have also attached a shorter article I wrote for the UK Podiatric Biomechanics Group from a decade ago on the same subject.

It is in these types of feet where the concept of subtalar joint (STJ) spatial location is very important in determining how difficult it will be to supinate these feet with foot orthoses. The STJ axis will be extremely medially deviated making the medial heel and proximal aspect of the medial arch the only area of the plantar foot that is medial to the STJ axis and, therefore, the only areas of the plantar foot where a foot orthosis may exert a STJ supination moment. The supination resistance test, which I first described in the DeValentine chapter, is helpful in appreciating the extreme forces that are required from the orthosis pressing in the medial arch of children with feet such as this in order to produce STJ supination. Craig Payne has built a supination testing machine using the concepts from my supination resistance test and has published papers on this and other supination resistance type devices are currently being worked on by other researchers to determine the supination response of the STJ to medial arch pressure.

Jeff has given some good recommendations for foot orthosis design, I would also recommend putting this boy into high top hiking boots/tennis shoes to the increase supination effect on the STJ from the foot orthosis. I treat children like this quite commonly in my practice with foot orthoses.

Hope this helps.

 

Many thanks for your views Kevin and the literature, I've got a much better idea of what I am dealing with now thanks to Jeff and yourself. I was sure that a vertical talus was rigid, but have never seen one and this pt's feet were so flat especially in the saggital plane it made me wonder. I have advised high top footwear for him already, but will look at orthosis options at the next appt.

Regards

Marc

 

Good results in Spain with UCBL along with medial heel skive. Only in flexible feet. Orthopedics surgeons and podiatrist treated those kids ( before middle 90,s) with metal orthesis ( The insquisition was not forbidden about that ages). Many patients with a supposed pediatric vertical talus who come to see us nowadays has serious pronation related pathology (plantar fascitis most of them). With this patients I use accomodation orthesis with longitudinal medial arch, and heel skive elevation, with great results, but never using a functional orthesis.
Happy new years for everyone, long life for podiatry