skin breakdown ex fix.

RE: skin breakdown ex fix.

Michael Woodhouse — Sat, 09 Jan 2016 21:23:10 GMT

An unfortunate outcome, but thanks for coming back with an update.

RE: skin breakdown ex fix.

chris Jones — Sat, 09 Jan 2016 10:17:16 GMT

Thanks for the replies.

Buried my head in the sand on this one

The area broke down as described but stabilised and she was doing ok until she jumped down some steps, the fracture site became unstable again. The owner didn't want any further surgery, plate, ex fix or amputation and opted for pts. very sad really and looking back I should have done things differently. live and learn but not a great way to do it.

I didn't bone graft at the time as I felt that the reduction with the lag screws was good and the general stability was adequate, again you live and learn.

thanks for the help

RE: skin breakdown ex fix.

James Dunne — Sat, 09 Jan 2016 09:01:04 GMT

Hi Chris

Sorry for the late reply. Most of what can be said has been said already.

A couple of things; I've scanned the other replies but not read in great detail so apologies if the below is re-inventing the wheel.

1. If the fracture started 2.5cm proximal to the talocrural joint, there is no way you will get two full pins in the distal fragment without weakening the existing bone. The best option for that type of fracture is a ring fixator tied into a type I(b) linear frame; so-called hybrid fixation. In situations where a ring is not possible, then I would use a type I(b) fixator with one half-pin medially and one half-pin cranially; one other cranial pin proximally and two medial pins proximally and link these two with a connecting bar to increase stiffness. This should be done after lag screw placement; there is nothing wrong with using ESF to protect a load-sharing repair - it works a bit like a plate placed in neutralisation mode.

2. Your screws will likely have to be removed once the fracture is healed. My advice would be to continue to manage the wound as you would an open wound. If there is a healthy granulation tissue [GT] bed forming, then use non-adhesive dressings with a lubricant between dressing and GT and change every 24-48 hours is fine. If there is exposed bone with no GT then drill small holes in the bone [0.9 - 1.1mm] to cause bleeding and allow for vascular outgrowth.

3. I take it you bone-grafted the dog given the age? it would be wise given the poor biology of this fracture [location, open, poor soft tissue coverage, age of patient etc etc]. There is nothing wrong with doing a delayed cancellous graft if you have not done so already.

4. If the fracture fails you could always let the skin heal, use the ESF for support until the skin is intact then remove your ESF and plate the fracture; sort of a delayed definitive fixation which we are using for some of these.

Of course, finances, facilities and preferences/experience can all alter the possibilities!

Hope the above is of some help

James

RE: skin breakdown ex fix.

Ian Paterson — Fri, 08 Jan 2016 23:00:52 GMT

Difficult to comment without seeing radiographs but agree with all of above. Leave the implants you have opted for where they are if the fracture is stable and the pain is under control. Manage the open wound as discussed, conservatively. Bone will definitely heal in the presence of infection as long as there is stability - and that's probably the big issue here. With patient age and fracture location there's a reasonable chance the ESF will fail before you have functional union. We've all been there & it's easy to suggest alternative repair methods in retrospect! Sedation/radiography every 3-4 weeks would be worthwhile so that you can manage client expectation as you go along. There's nothing like a fracture repair to come back and smack you in the face 6 weeks later....as my ophthalmologist colleague insists on reminding me post op! Keep us posted..

RE: skin breakdown ex fix.

Michael Woodhouse — Tue, 22 Dec 2015 23:21:52 GMT

[quote user="cmj"]the skin is tight and I have been flushing with saline tid and honey dressings and allowing the skin to slough to its full extent which it seems to be halting at that size.[/quote]

If you've cleaned anything dead away then I'd fill with hydrogel, stick a Allevyn on and leave things alone for maybe a week. The granulating tissue is delicate and I worry people want to do too much.

RE: skin breakdown ex fix.

cathal rafferty — Tue, 22 Dec 2015 23:15:01 GMT

Ross and john's point about using rigid and less rigid fixation types is true but you are where you are.

i wouldn't worry too much about the skin, it will just have to granulate and the only thing you can do to encourage this is remove contamination and keep the wound moisture content about right.

i would say definitely don't remove any implants at this stage. Fractures heal just fine in the presence of infection so long as it is stable but you may have to keep the dog on abs whilst it does.

The problems might come weeks down the line. An 11 year old dog with an open fracture of a bone with a poor soft tissue envelope will take a long time to heal.. I would say longer than you'll get out of your frame.

did you place a bone graft? If not i would say wait until it is granulated over then in 3-6 weeks consider going back in from another angle and placing graft to accelerate healing. It's quick, cheap and low morbidity.

further down the tracks if pins loosen they can be remove and another replaced close by, but you risk making a lot of holes in a small piece of bone.

RE: skin breakdown ex fix.

chris Jones — Tue, 22 Dec 2015 21:52:49 GMT

thanks for the replies.

the esf pins were predrilled with the correct size drill but at the site of the positive threads it was hard to drive, bigger drill led to poor interface and I felt it was due to the v hard bone but also a c**p chuck (new one arrived today after a bit of mild ranting). I feel now that if I had used a plate I would be in a worse situation as the skin slough started away from the wound on the dorsal aspect of the tarsus and surely plate exposure would be a more hopeless situation.

the lag screws reduced the fracture very well and the ex fix is very stable (so far) but its really how to deal with the wound that I am worried about

The pins were 4mm shank positive threaded. distal 1 x full mid thread, second half end thread, above 2 x end threads. bards on medium ke clamps medial bar with lateral bar (x2 clamped together) wrapping around the cr aspect of the tibia.

I was thinking of using a pin in place of the lower lag screw into the frame but went with the screw. may be an option to replace it as has been suggested. interesting what Ross suggests about lag screw and esf as poor combinations, not used this myself before and can now understand why its not a great idea, live and learn and all that.

the leg broke in the garden, she caught it between two rocks chasing a cat so probably not a path fracture. will try to upload some photos and rads

My thoughts are really keeping it clean and allowing second intention healing.

despite the breakdown and screw exposure she is still happily weight bearing.

I am not currently over worried about the fracture site (infection etc aside) and healing (just blindly hoping possibly) but more concerned about the skin deficit although fracture site infection and micromovement leading to failure is a possibility. its always the uninsured ones that get like this!

will try to get some rads and photos uploaded tmrw ( will put my tin hat on for the fallout

regards

chris

RE: skin breakdown ex fix.

Ross Allan — Tue, 22 Dec 2015 21:28:45 GMT

I would suggest that the lag screws may not be great in combination with ESF.

My thought is based on lag screws aiming to correcty anatomically and importantly rigidly stabilise the fracture and allow primary healing thus minimising callus formation.

The ESF meanwhile may not give the total stability that is likely required to protect the lag screws well enough. The micromotion around the ESF will increase the risk of implant failure. This micromotion is however what would actually encourgae good callus formation were the screws not present. I would therefore not normally use these two systems together.

Xrays/pics would be good, but one idea may be to remove the screws, and place a cranial positive profile ESF pin int he distal tibial fragment, and tie this in to the medial bar of the ESF. In my mind this triangulation with the mediolateral pin and cranial pin will offer good stability for the distal fragment, and could also be repeated for the proximal fragment if wished.

These are just ideas, and it may heal OK eventually...

RE: skin breakdown ex fix.

John Flynn — Tue, 22 Dec 2015 19:32:17 GMT

Hi Chris,

I'm an ex fix hobbyist at best, so don't pay too much attention to my thoughts, but in case no-one more qualified stops by this side of Xmas:

[quote user="cmj"]11 year old lurcher with a distal oblique tibial fracture 10 days ago.[/quote]

Sounds obvious but I can't be reminded of this too often myself so: checking definite history of trauma and no radiographic indications of pathological fracture

[quote user="cmj"]The fracture started 2.5cm proximal to the tarsel joint and was open.[/quote]

Ouch...

[quote user="cmj"]I felt (?wrongly) that there wasn't enough bone stock below the fracture for a plate or a pin but I may be able to fit an ex fix in there and lag screws (the oblique part was 5cm long).[/quote]

I think I can imagine the rough fracture configuration you describe and I'm never sure how best to do these. In a younger patient I would definitely IM pin and cerclage wire this, but I appreciate that's not too trendy these days. In a patient of this age, I'd be a bit more wary, but brandishing my retrospectoscope I'm not sure that the fixation you describe is necessarily more stable than pin/cerclage would have been - others' thoughts? I think a plate can almost always be fitted even if not ideal and might have been better - with a thin pin a rod/plate combo may well have been an option (but with less chance of getting decent lag fixation with pin in way...) if lacking cortices distally when plating in an obliques fracture (and the fracture orientation is appropriate) then instead of lag screwing sometimes can place distal fracture line screw to engage both cortices as placement screw (if that's correct term?) so get more cortices engaged in distal fragment if that seems more important than generating more compression across fracture site. If you have circular ex fix, then I think it comes into its own in these case if wishing to ex fix with a small distal fragment, but that's not to say that can't be done well without.

[quote user="cmj"] I was planning a bilplaner ex fix with 2 full pins top and bottom and another half pin minimum in the distal fragment and 2 half pins above. I was hoping to get more pins in the distal fragment but there wasn't enough room. [/quote]

Sounds a reasonable enough plan to me. Sometimes can get away with a decent full pin and a smaller smooth half pin in distal fragment in cases like this. placing additional pin in different plane is always an option also and nice thing with ESF is can often add more pins a week down the line having thought about case if decide fixation applied is not stable enough. a transarticular frame can be applied as well with pins down into calcaneus and beyond to help stabilise the distal fragment if required and a stiff hock after frame removal is better than non-union.

What size and type of ESF pins and clamps and connecting bars were applied?

[quote user="cmj"]couldn't drive the full pin proximally[/quote]

If you're not already, I'd recommend ALWAYS pre-drilling any ESF pins - will give you longer-lasting, better pin-bone interface.

[quote user="cmj"]I half pin above fract line 1 below. 2 x lag screws preplaced before ex fix pins reduced the fracture nicely. bar medially with a second pair of bars connecting the lateral full pin with the medial proximal pin (? modified biplanar?).[/quote]

I'm finding the exact ESF frame hard to visualise, but couple of thoughts:

1) the combination of lag screws with ESF is not one I normally do and is perhaps not ideal. Effectively this is accurate anatomic reduction to load-sharing with lag-screw repair (aimed at primary bone union) and then an ESF (generally aimed at secondary bone healing) to protect the lag-screw repair. This is better than no protection of the lag screw repair, but is probably not the robust, inflexible support you would ideally like in this case.

2) I've forgotten what I was going to type here - I'll edit if it comes back to me!

[quote user="cmj"]chuck issue[/quote]

get a new chuck key if needed - it always wears first.

[quote user="cmj"]post op she is using the leg very well [/quote]

That is always good news for fracture healing.

[quote user="cmj"]having skin necrosis dorsal to the tarsus extending into the medial skin wound and exposing the distal smaller lag screw head. size - 1cm of distal wound and 2.cm x 1cm of dorsal tarsus area. exposing 1cm of distal tibia around lag screw.[/quote]

Bummer.

[quote user="cmj"]

the skin is tight and I have been flushing with saline tid and honey dressings and allowing the skin to slough to its full extent which it seems to be halting at that size. the skin will be too tight to close and I am considering my options.

1 the distal screw will have to come out at some point I feel, I have left it so far

2 skin graft or second intention healing

she seems comfortable and is on nsaids and clindacyl + pot amox.

[/quote]

second intention healing every time.

nice thing about fixator frame is dressing wound is usually quite easy as frame keeps dressings on.

I generally cut allevyn pads (sterile scissors) with slits to allow passage through pins and then little tape once placed over cut bit so it ain't going nowhere and pack sterile swabs under fixator frame and then soffban over the top of everything and vetwrap, leaving the paw exposed.

Quite a hastle, but I think regular changes and flushing like you are doing for first week is well worthwhile.. Wet-to-dry dressings or even sharp debridement can be helpful to remove dead tissue and speed things up.

It can heal over the screw and I might leave it in place initially while I see what happens?

[quote user="cmj"]what are your thoughts on how I should go from here with this wound. the pins seem fine so far and she is mobile and comfortable.[/quote]

Given the devitalisation of the skin, I'd personally not try anything else with fracture stabilisation presently, btu would manage the wound as you are and if healing over with healthy granulation tissue then do soem xrays to see what the fixation is looking like in 6 or 8 weeks time. However I'd be concerned that fracture healing will be slow for a number of reasons here and the fixation may not be robust enough to survive that. Either I would just see what happens and if pins coming loose then deal with problem then, or I might consider premptively adding half or full pin proximally and then extending frame down distal to tibia in a week or 2 when wounds looking better perhaps and less concerns about further devitalisation of skin?

Final thought: I have seen lots of fractures heal that were not textbook fixations and at greater risk of failure - just because things aren't ideal with the patient and problems might be more predictable doesn't mean that it won't do well, so I would at very least give it time after all your hard work to see what happens - using the leg is always an encouraging sign for fracture healing.

RE: skin breakdown ex fix.

Eamon McAllister — Tue, 22 Dec 2015 18:33:54 GMT

Could you post some photographs +/- radiographs?