LEAP (Fusion) for Lat Humeral Condyle Fractures

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Anthony Todd — Tue, 11 Feb 2020 15:35:43 GMT

Yup, didn't realise there was a lower humerus too!

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Beats — Tue, 11 Feb 2020 14:50:47 GMT

Hi Anthony,

The bone needs to fit back together as perfectly as you can (this is the function of accurate reduciton and the lag screw).

This thread is primarily about what to do with the lateral epicondylar ridge fracture - that is the bit of bone laterally connecting the condyle at the bottom to the humeral shaft. I tend to place a k-wire here as has traditionally been done, but am discussing the merits of a plate instead and specifically the LEAP plate for this purpose: this is not instead of a screw across the fracture in the condyle, but in addition. The aim of this is not to give better initial function or improve alignment, but to reduce risk of eventual failure I believe?

A "locking plate" is like an external fixator (ESF) applied internally from a mechanical point of view - it is not intended to contact the bone perfectly [like a normal bone plate which is simply tightened on to the bone and therefore needs to contact the bone well] and is thus ideal if wishing to plate an irregular bit of bone that would be hard to contour to.

Rob is explaining that the PLATE does not need to contact the bone, not that the BONE does not need to be properly lined up with the BONE.

I think everyone is in agreement that good accurate reduction is the main aim for stability and function and that a screw across the condyle is used to maintain this. The only questions are therefore:

1) How best to place this screw, and what type of screw to place across condyle

2) What fixation to place on lateral epicondylar crest (pin or plate, and if so what type of plate), assuming simple reducible lateral humeral condylar fracture.

Hope that clarifies.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Anthony Todd — Tue, 11 Feb 2020 14:22:22 GMT

[quote userid="4181" url="~/001/veterinary-clinical/small-animal/orthopaedics/f/discussions/28864/leap-fusion-for-lat-humeral-condyle-fractures/219360"]

Anthony Todd said:
The plate described is unlikely to make perfect contact with the opposing bone due to, even minor, variation in the shape of the anchoring bone or placement of the plate

It is specifically designed not to make perfect contact

[/quote]

I can only say that "our" clamp seemed to give perfect function and quickly.

Perhaps we were just lucky, in that the #condyle was a perfect fit, or seemed to be. Seems strange, to me, to "reduce" a fracture so there is not a perfect fit particularly in this site. ie an important joint.

Surely the joint doesn't function normally unless the two joint faces, ligaments etc. coincide/mate-up well ??

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Dinu Catilina — Mon, 10 Feb 2020 23:16:15 GMT

[quote userid="12930" url="~/001/veterinary-clinical/small-animal/orthopaedics/f/discussions/28864/leap-fusion-for-lat-humeral-condyle-fractures/219397"]Dinu, what type of self-compressing screw do you use? Is ti the VI-marketed HIRS one or a "standard" human ones like Orthofix[/quote]

What I use now is this one form N2:

http://n2-uk.com/product/iohc-screws/

I used the VI one but it wasn't cheap. The special drill was also expensive and adding the DBM putty to it made a serious difference in price.

I don't know if there are any advantages over a 4.5 cortical if you also use a plate. I used both with good success but I prefer the self-compressing screw in cases where there is only intracondilar fissure. I got used to it and I use it in all cases now. I like that I don't have to drill more than once through each fragment. The drill bit is 3.2 mm so less rotational forces on the fractured fragment, easier to hold.

I also do inside-out if it's an older or comminuted fracture and I'm not sure about reduction. I compress with pointy bone holders and mark the bone edges with needles for accuracy.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Eamon McAllister — Mon, 10 Feb 2020 21:16:44 GMT

this: https://www.pattersonvet.com/Supplies/ProductFamilyDetails/PIF_35689 ?

That’s the one.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Beats — Mon, 10 Feb 2020 20:49:05 GMT

I think two things being talked about here:

1) stabilisation of lateral epicondylar ridge (pin versus plate, and LEAP plate specifically): there was a retro study (link in first post, also found this https://www.zora.uzh.ch/id/eprint/138628/1/Biomechanical_Comparison_of_the_use_of_a_Supracondylar_Kirschner_Wire_and_an_Epicondylar_Plate.pdf) that suggested that using a plate rather than pin may decrease complications, hence my interest. [the Zurich link there is an in vitro study and only on comminuted lateral epicondylar ridges, whereas I'm more thinking of regular non-comminuted fractures]

2) Method and type of screw placed across humeral condyle.

Regarding (2): I've never seen a condyle clamp in action. Was it one like this: https://www.pattersonvet.com/Supplies/ProductFamilyDetails/PIF_35689 ? I tend open the fracture and rotate the lateral fragment of condyle cranially (hinged on cranial tissues and lateral collateral ligament) after dissecting off the anconeus caudally, and then drill from inside out of fracture, usually starting with small drill bit or k-wire and then increasing size up to 4.5mm drill bit. I'm not sure I'm totally happy with this approach, so interested in alternatives. i reckon that at least if my angle isn't great (it often isn't...) across the condyle, the screw will be in the middle of the condyle centrally.Then it's usually relatively straight-forward to reduce with finger pressure and hold with large fragment forceps across the condyles to drill into medial half of condyle with 3.2mm pilot and tap and place 4.5mm cortical screw.

If using condyle clamp, do you start the same and then just place instead of fragment forceps (limited benefit?), or do you drill from lateral to medial in which case if lag screwing do you use a drill stop to ensure don't over drill into medial fragment too much with 4.5mm drill bit? Does that question make sense?

Dinu, what type of self-compressing screw do you use? Is ti the VI-marketed HIRS one or a "standard" human ones like Orthofix (https://www.orthofix.com/wp-content/uploads/2019/01/RIBI-1906-PL-E0.pdf) ? What do you feel are advantages? Are the advantages big enough to consider switching if I'm used to 4.5mm cortical bone screw placed "inside-out" in lag fashion?

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Rob Loxley — Mon, 10 Feb 2020 08:48:22 GMT

[quote userid="5904" url="~/001/veterinary-clinical/small-animal/orthopaedics/f/discussions/28864/leap-fusion-for-lat-humeral-condyle-fractures/219331"]The plate described is unlikely to make perfect contact with the opposing bone due to, even minor, variation in the shape of the anchoring bone or placement of the plate[/quote]

It is specifically designed not to make perfect contact - look up the principles of limited contact plates, and associated locking screws

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Dinu Catilina — Sun, 09 Feb 2020 12:17:17 GMT

I think there is a misunderstanding in what this plate does. All fractures will still be repaired with compression between the lateral and medial epicondiles (lag screw or my preferred self compressing screws). The plate is an augmentation to the repair to counteract rotation. The plate is locking so doesn't need perfect contact or any contact with the bone and it will not create a gap at the fracture site. There are two fracture sites anyway.

The intracondilar screw will go in first.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Eamon McAllister — Sun, 09 Feb 2020 11:39:27 GMT

I had a condyle clamp which I purchased from Vet Instrumentation. This allowed the fracture to be repaired with a lag screw which applied essential compression to the fixation. I too don’t think that contact and compression could be achieved as easily with a plate.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Anthony Todd — Sun, 09 Feb 2020 10:13:14 GMT

As always an unexplained "disagree" helps nobody.....

The plate described is unlikely to make perfect contact with the opposing bone due to, even minor, variation in the shape of the anchoring bone or placement of the plate thus probably leaving a gap at the fracture site [IMHO]. Whereas the transfixing screw always ensured a perfect fit in a simple fractured condyle.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Anthony Todd — Wed, 05 Feb 2020 14:12:05 GMT

We used just put a home-made condyle clamp across both condyles and then screw through both, lining the drill hole up by the extended threaded arms of the clamp.

Usually the fractured condyle was a perfect fit with the "good" one. A cup on each inner side of the clamp arms [with a hole for the drill and screw lined the fragment/condyle up perfectly.

MJV was a master....20mins

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

James Dunne — Wed, 05 Feb 2020 13:48:05 GMT

Hi, I have not used the plate but it is well-designed and those people who use it are pleased with it. I currently use PAX or SOP for locking implants, but the LEAP plate looks much lower-profile and since it is precontoured, it eliminates some of the risk of placing screws intra-articularly.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Dinu Catilina — Tue, 04 Feb 2020 21:59:56 GMT

I never used this particular plate but I would plate the lateral epicondile in any adult and only pin puppies. I've not done the hundreds mentioned in that study, rather tens.

Seems like an interesting idea with that low profile I currently use Evolox plates or SOP in a smaller dog which can be bulky.

RE: LEAP (Fusion) for Lat Humeral Condyle Fractures

Michael Woodhouse — Tue, 04 Feb 2020 21:30:58 GMT

An extra £350 cost to me is going to make it so expensive I might was well refer the case. If 72% of the cases that decline referral (either due to cost or other reasons) end up fixed, then I'm quite happy.

I've only ever done a few, so no expert. Last one I referred remains very lame so glad I never touched it!