Foot Problems

[lehughes]

Hi Laurie:
Hope all is going well. I have a case that I need to pick your brain on. A vet from L.S.A. sent a 11 yr old 35 kg LabX F/S dog to me to get an orthotic made for the LHL. I have done a full exam on this dog and I am not sure if an orthotic is going to work well on this dog. The history is that it was rescued from a reserve as a 10 month old puppy, and it had an tibial crest avulsion that a skilled veterinary surgeon wired the tibial crest back on. The surgery apparently went well and the dog had no issues until about 3 yr ago and O noticed dog to be limping on the LHL and with time the paw started to flatten out. In the past year the LHL digits have hyperextended and deviated laterally so that the dog primarily WB on the medial aspect of the LHL paw (I have attached photos). Otherwise she is in good health. Recent xrays taken at L.S.A. Vet Clinic showed mild bilateral stifle OA and at the MT-P1 joints of all LHL digits.

On exam I found the dog to be normal neurologically except for no LHL patellar reflex. However....the tibial crest palpates to be more dorsal in position than expected and the patellar ligament does not became fully taut during full flexion of the knee joint and I suspect that absent patellar reflex is more from laxity of the patellar ligament than from a neurologic deficit. The left patella glides on the medial trochlear ridge but does not ride up on the top of the ridge. Both knees have a mild decrease in stifle extension and medial buttress and no drawer.
LHL: Quadriceps muscles has mild decrease in mass and tone and thigh girth is 3 cm < than RHL.
LHL during standing - Dog WB primarily on the medial aspect of the paw with all digits deviated laterally with hyperextension on all digits.
The MT-P1 joints are all thickened dorsally and have decreased AP and lateral glides. The medial digital pad is thickened and callused. All digits can flex upon stimulation. The hock is dropped about 1" lower than normal and is positioned slightly medially. The knee is deviated slightly medially (mild stifle valgus). LHL stifle - 47 degrees flexion and 150 degrees extension. Stifle is mildly decreased on extension but is not painful for the dog.
At a walk the LHL knee has both decreased flexion and extension in movement and plants on the medial paw for WB.
The spine is quite normal for this age of dog - has some mild TL spasm.

My thinking of the dog's WB anomaly on the LHL paw is that the originally avulsed LHL tibial crest was surgically repaired leaving the crest more dorsal in position than normal thus creating mild patellar tendon laxity (that the dog lived with for most of her life through mobility compensation), but now that she is a senior and losing muscle mass and can't compensate so much and flex the stifle (and with the mild riding of patella on the medial aspect of trochlear ridge) this causes the leg to have to WB on the medial aspect of the paw with the associated lateral deviation of the hyperextended digits.
Do you agree with this thinking, that this dog's deviated paw issue is likely to be structural from a lax patellar tendon from the tibial crest luxation from 10 yr ago, or am I missing another more likely cause for this lateral digit deviation with WB on the medial aspect on the paw? And then the next question is what can I do to help this poor dog? I believe that an orthotic will nicely place the paw back into normal position, but if the stifle can't extend properly due to a lax patellar tendon, will this dog be able to move the orthotic properly when walking?

In meanwhile I have started the dog on the following HEP : 1. digital traction and compression to make the deviated arthritic toes more comfortable. 2. tail traction for the TL epaxial spasm. 3. Stimulate the plantar surface of the LHL toes to encourage digial flexion. 4. proprioception exercises on LHL.

Thanks so much Laurie. I really appreciate your input on this case. If you believe that I am completely out to lunch on my thinking, let me know.
JS

[lehughes]

Hey J.!

All is chaotic for me down here… figuring out our new life as ranchers, amongst all of the regular stuff we were doing already!

Anyhoo… on to your case. I’m going to just type as I think. Because it’s not a straight forward case, I would normally talk through it and yes or no my ideas. So I’m just going to do the same thing in type-mode!

1) the patellar tendon laxity. Could be, as you guessed, a matter of it being pinned to high. OR, I did see one dog (back during my CRI teaching days) where the tibial tubercle pinning failed, and the patella floated upwards. There was function and dysfunction all at the same time. And the dog had a hyperflexed leg when he walked. The only point here, is that yes, likely the patellar tendon is not taut, but it might be due to a failure of fixation OR a high pinning of the tibial crest. Either way, it’s not providing ideal biomechanics.

2) usually when I see a flattened foot, it’s because the dog is increasing weight bearing on that leg as a compensation for an issue on a different limb and the ligamentous structures break down in the weight bearing foot. However, that’s not the problem here - as clearly evidenced by the lack of quads tone and thigh circumference. So where does that leave us? I start to think about a failure of the SDFTs. In particular a SDFT luxation / displacement. This could account for flat toes as well as the limb positioning. And if that’s the case, then at this point in time, it’s chronic… so surgery may not be a good option, and the dog it 11.

3) OR… as you mention, the lack of end range extension, and the perpetual semi-flexed position of the stifle, may be compromising foot placement and positioning. But to be honest, the foot flattening and turning doesn’t quite add up as a matched scenario. I’m going through a rolodex of past dogs in my head..., and I’m not connecting the two. And the ‘suddenness’ of this happening 3 years ago - lameness and then the flattening of the foot… sounds to me like something a bit more traumatic happened and if not traumatic, then a sudden, spontaneous failure of 'something’. Even with the patellar laxity - grade 1 as it sounds to me… they don’t tend to go valgus at the stifle, or flatten in the foot. So… I am liking the sounds of option # 2 better now!

4) Now what to do!?! A splint to help the foot and tarsal position will make the dog have to adapt to an new gait strategy because of the lack of stifle extension. I’m not sure what you’d accomplish by bracing! I do think that perhaps a bootie would help (i.e. the Therapaw ‘cushy paws’ for indoor use and a all-weather boot for outdoors.) I don’t think that bracing is the answer. HOWEVER, upon taking the Bracing/Splint Course with Ilaria (of Therapaw) she was always saying ‘do a mock-up’… so why not test out creating some support by simply wrapping the tarsus and foot. See how the dog functions with added support / stability / rigidity to the tarsus and foot - simply vet wrap or bandage and vet wrap. See how the dog moves. If okay… then you might proceed with a hock brace that extends down to the foot and provides a cradle for the foot to sit in.

5) I think you just teach some specific strengthening for the LHL to work on quads, glutes, and some gastrocs (step ups, squats, sit to stands with front feet elevated, side stepping to the left, etc).

I’m going to post this to the forum as well.

Oi! This is a tough one, especially as a distance client!
I hope this helps with some thinking anyways!

All the best,

Laurie

[drwall]

I would love to see the radiographs of your patient. The pictures and description in the lower left pelvic limb are suggestive of "dropped toe". This is injury to both the superficial and deep digital flexors. I suspect with the chronicity there is likely damage to the static stabilizers of the metatarsal-phalangeal joints as well with resultant joint dysfunction and djd. Interestingly enough this injury is seen in racing greyhounds and hunting dogs both of which return to athletic performance with out much therapy at all. I doubt that this is the real problem. Everything in you description supports chronic cranial cruciate ligament disease, possibly bilateral. I have never heard of a description of major orthopedic issues from a functional shortening of the patellar tendon. Dogs with CCLD have been shown to ambulate the pelvic limb in a slightly abducted state and this could potentially be the cause of the increase weight bearing on the medial side of the paw. Just a thought! It would make sense that chronic dysfunction in the pelvic limbs could result in muscle dysfunction in the dorsal thoracolumbar and lumbar paraspinals, however, I doubt that it is muscle spasm, but rather myofascial pain and dysfunction.

Rick Wall

[lehughes]

Hi Laurie
Thanks so much for your speedy response. What are you ranching? Cattle? Sheep? Horses? Goats? All the above? Man, you're a busy woman.
That is a great piece of wisdom about the flattening of the paw would only likely be in compensation for overweightbearing because of injury in another limb (which I see quite frequently in front legs when the opposite elbow is bad) or from decreased function of the flexor tendons. So in this dog's case I agree that it would have to be the flexor tendon issue.
I really love your idea of making a mock splint with vet wrap. I assume that I need to make it so that the paw will WB fully on the entire plantar surface of the paw and probably use some bandage tape on the medial aspect of the leg to try and position the paw normally. I am going to give this a try first.
I'll let you know how this works out and whether or not we move onto a hock apparatus as you described below.
Thanks
J

[lehughes]

Hey Rick,

I'm going to reply to you here, since the original poster posted via e-mail, and I just reposted it here.
I've seen those flattened toes as well - with the detached SDFT at the level of the toe - what strikes me as different with this case is the deviation of the foot and toes, and the fact that it's more than just one or two toes being affected. Those things hit be as being unusual for a SDFT avulsion.
The gait of the CCL injured leg tends to be a bit more externally rotated as compared to abducted - external rotation allows for the hip to swing forward without making the stifle go through a full range. Neither would increase weight bearing on the medial toes or a medial deviation of the toes or a valgus presentation of the stifle.
All in all, this is why I questioned a SDFT luxation off of the calcaneus.

Hopefully J. Will update me when she re-examines the dog!

Cheers,

Laurie

[drwall]

Laurie,

Thank you for your comments;

-----"The gait of the CCL injured leg tends to be a bit more externally rotated as compared to abducted - external rotation allows for the hip to swing forward without making the stifle go through a full range. Neither would increase weight bearing on the medial toes or a medial deviation of the toes or a valgus presentation of the stifle.-------

I just don't appreciate external rotation of the pelvic limb in CCLD, acute or chronic and I video all of my rehab/sports med/chronic pain patients for video evaluation.

In "Kinematics of the ACL-deficient canine knee during gait: serial changes over two years" Tashman S, et al. J of Ortho Res 22 (2004) 931-941.

this study use the pondnuki model of transecting CCL surgical and compared to a control group. Tantalum sphere were implanted in the tibias and femurs to provide high-accuracy radiographic targets via radiographic sterophotogrammetric analysis during kinematic evaluation.

from the paper:
("ACL loss did not create consistent changes in internal/external (I/E) rotation knee rotation, but a trend (non-significant) towards reduced internal rotation was observed.")

("At the first post-transection (2 months postop), the amount of abduction was only slightly elevated. This difference increased rapidly over the first year, to 3.5 degrees higher than ACL-intact stifles.

Rick Wall

[lehughes]

Rick,

Ah... I think we're looking in different places.

I'm seeing / thinking about external rotation from the hip - not a rotation of the tibia.

Laurie

[drwall]

Laurie,

Thank you for responding. Interesting discussion! Thanks for the forum!


I think of the stifle joint as hinge type joint (trochlea) allowing flexion and extension. Both the femoral condyles and tibial condyles are convex with trochlear stability being the result the menisci limited rotation is possible in certain positions. However, during ambulation external rotation of the hip (spheroidal joint)would result in external rotation of the entire limb, including the stifle. Such did not appear to be the case, even with CCL deficiency, in the study quoted.

Thanks,

Rick

[lehughes]

I think it's a nomenclature thing...
In the example of the dog in the picture I attached (my business partner's lab with 7 total surgeries between his two stifles), you can see both an abduction and external rotation. I would say that the external rotation allows for the abduction. And subsequently a 'slightly' more functional gait.

Laurie