Dr Delureanu FlorinCristian
Veterinary Center Otopeni
An ample loss of skin with underlying tissue and exposure of deep components (eg. tendons, ligaments, bones) define a degloving injury. This kind of wounds are most frequent seen on the distal limbs, medial tarsus/ metatarsus. The main cause of deglowing wounds is car accident, special when the animal is dragged or pushed by a moving car. In all of the cases bacteria and debris are present in the wound.
Free grafts are described as a piece of skin detached from an area of the body and placed over the wound. There are two tipes of free grafts when we talk about graft thickness: full thickness (epidermis and entire dermis); partial/split thickness (epidermis and a variable portion of dermis). Skin grafts are using when exist a defect that cannot be closed by skin flaps or direct apposition. Two factors influence skin graft survival: revascularization and absorbtion of the tissue fluid.
A 4 years old female shorthair cat, weighting 3,25kg was presented to our clinic. Before that, the owner was at another clinic for consult and he was disappointed because they recommended euthanasia or amputation of the limb. Besides, the first vet treated the cat with Amoxi+Clavulanic Acid and Nekro Veyxym. The owner said that she went missing for about 10 days.
After a thorough clinical exam we found that all was normal excepting the degloving injury. The back right leg was affected. There was a massive inflammation with infection and a lot of debris on the dorsal surface of metatarsal area and ventral, above metatarsal pad. On the dorsal surface of metatarsal area (Picture 1). Besides, also in the ventral area, another wond proximal to the metatarsal pad and 3 deep holes was identified at the base of second, third and fourth finger (Picture 2). It could be distinguished the chronic aspect. A third lesion was registrated on the same leg, in the medial aspect of the thigh. This wound was deep with a circular shape (Picture 3). We estimated that the lesion occurred about two weeks ago. We register pain and high local temperature after palpation. The cat was stable, normothermic, with normal color on mucous membrane, CRT 3seconds and normal superficial lymph nodes.
Radiograph of the affected back limb
Two x-ray views was made to eliminate bone changes or foreign bodies (Picture 4a, Picture 4b).
Picture 4a, 4b- Specialist describe: Suspected slight thickening of phalanges cortical 1 fingers 3-4 and gently bending them. Soft tissue swelling of the tibio-tarso-metatarsian region.
After evaluation, the initial recommendation include a good wound management under anesthesia. Before surgical debridment (Picture 5a, 5b), culture was done.
Picture 5a and Picture 5b – Dorsal and ventral aspect of the lesions after surgical debridment
Next, wound lavage was initiated with one bag of 500 ml of worm saline (the most easy way to deliver fluids on the wound is to connect the saline bag with a administration set to the syringe and needle with a 3-way stop cock a large amount of liquid is needed to be effective).
Finally, this first stage ends with a wet to dry bandage. A primary wound closure was performed for the lesion placed on the medial aspect of the thigh (Picture 6), after intensive cleaning, removal of foreign bodies and dead skin .
Empirically the cat receive Cefquinome until the result arrive and for pain management we administered Tramadol 3mg/kg and Meloxicam 0,1-0,2mg/kg. The cat recover well after anesthesia.
One day before performing surgery, we recived the culture result. Streptococcus canis (++++) was identified and was sensible to many antibiotics. Amoxicilin+Clavulanic Acid (Synulox) was initiate for general therapy and chloramphenicol ointment (Opticlor-Pasteur) for local therapy.
Next, a full thickness mesh graft was used on the dorsal aspect of the limb due to the length and depth of the wound and the other wound was left for healing by second intention, both being protected by bandages. In the next 10 day the limb wounds was treated in the same manner. Removal of bacteria, granulation tissue formation and the beginning of epithelization were supported by next bandages as follows: ·
Day 1 – wet-to-dry bandage was used after surgical debridment. (this kind of bandages adhere to the wound and remove the little layer of dead tissue when we take off). Soaked in warm saline 1-2 minutes before removing, they were changed after 24hours one to the other. Cotton gauze was the primary contact-layer of the bandage.
- Day 2 and day 3
– moisture retentive dressing (MDR) – calcium alginate (Sorbalgon-Hartmann) was the primary contact-layer. It is good to use when it exist high exudate like in our patient (Picture 7a, 7b).
- Day 4,6 and day 9
– moisture retentive dressing (MDR) – hydrocolloid (Hydrocoll-Hartmann) was the primary contact-layer because the discharge decreased (Picture 8).
Describing surgical procedure:
Preoperative surgical site preparation: The cat was placed in left lateral recumbency, with the wound exposed. The limb was clipped entirely and povidone iodine and alcohol was used for aseptic surgery. Sterile warm saline 0.9% was use for wound lavage. Meanwhile a colleague prepare the donor site in the same manner- lower cranio-lateral thorax (right side). Almost 1mm of epithelium that has started to grow from the wound edges over the granulation tissue was removed using a thumb forceps and a no. 10 scalpel blade (Picture 9). A perpendicular incision was made right at the edge of haired skin with epithelium. The wound was incised all around and after that the epithelium was removed by advancing the scalpel blade under the epithelium around
the wound. Then, undermining was performed around the wound edges. A fragment of sterile surgical drape was used over the wound to get the exact shape. The drape “pattern” was placed to the donor area.
To maintain the wound moist, i placed over it a cotton gauze moistened in warm sterile saline 0.9% while the graft is transferred.
The direction of hair groth was marked with a black arrow above the donor site so that the direction of the hair groth on the graft will be the same as the hair groth direction on the skin surrounding the wound. After that, the margins of the drape “pattern” was traced on the skin. The skin of the donor bed was incised with No.10 scalpel balde and removed using thumb forceps and Metzenbaum scissors (Picture 10). The defect left after removing the graft was primary closed by undermining and advancing the skin edges with walking sutures using 3-0 monofilament absorbable suture material and finally the skin was sutured in a simple interrupted suture manner using 2-0 monofilament absorbable suture (Picture 11a, 11b).
Preparing the graft
The dermal side of the graft was placed on a polystyrene board with a thickness of 10cm covered with a sterile drape and after that we fixed and stretched with 21G needles. The subcutaneous tissue was removed from the graft. Next, made parallel incisions was made in the graft, 0.5-0.7cm long and apart (Picture 12). At the end, the graft was placed on the granulation bed and sutured with 4-0 monofilament nonabsorbable suture in a simple interrupted suture manner. Additional tacking suture was placed to ensure the expansion of the mesh incision and allow the fluid drainage (Picture 13).
Choosing the right bandage after grafting and aftercare
It is important to use a nonadherent primary dressing. My initial choise was Grassolind (Hartmann), is sufficiently porous to allow easy passage of exudate from the wound surface, preventing maceration of surrounding tissue (Picture 14). The ventral metatarsal wound maintain hydrocolloid dressing (Hydrocoll-Hartmann) as primary layer. After that, a thin layer of chloramphenicol oinment (Opticlor-Pasteur) was used all around both wounds and over the graft.
Over the first dressings was applied 5cmx5cm compress (Medicomp-Hartmann) and a roll gauze was the second layer. After a few laps of gauze stirrups was placed to secure the bandage in place. Extemporaneous half “clamshell” splint (Picture 15) was made from plastic material wich was curved in such a way that the limb was fixed in semi flexion. The splint is a little bit longer than the extremity of the pelvic limb (“toe-dancing” position), thus provide a maximum relief pressure. In the proximal area, under the splint, I put cotton to prevent pressure injuries on the caudal aspect of the thigh. Applied from proximal to distal and with moderate tension, elastic warp was the final protective layer of the bandage and it was secured at the proximal end with tape.
The bandage was changed in day 1, 3, 5, 7 and 10 post op. In day 10 the suture material was removed from the graft and from the donor site. From day 17 to day 29 hydrogel (Hydrosorb-Hartmann) was used as primary bandage layer and the bandage was changed from 4 to 4 days. In day 29 no discharge was present in the bandage; the wound was completely healed and 0,2-0,4 mm of hair was present in the center of the graft.
A delayed healing occurred at the wound in the ventral region (Picture 16). From day 29 to day 59 epithelization has advanced very hard and granulation tissue has captured an appearance of ulcer (in this time the wound was asepseptic prepared and hydrocolloid and hydrogel was used as primary layer bandage and without the splint). In day 59 the wound was refreshed on the surface with a scalpel blade and laser therapy (Picture 17a) and medical Manuka honey (Picture 17b) was used daily for 14 days. After that, a complete healing was reached.
Illustrating wounds evolution after surgery
Day 11 after honey and laser therapy
Day 16 after honey and laser therapy
Comparing day 1 and after 3 Months