Surgical Approaches to Recipient Vessels of the Fore- and HindLimbs for Microvascular Free Tissue Transfer in Dogs

Effect of cranial tibial artery laceration on radiographic bone healing and perioperative complications in dogs undergoing tibial plateau leveling osteotomy

During tibial plateau leveling osteotomy (TPLO), the laceration of the cranial tibial artery (LCTA) may occur, and the ligation of the cranial tibial artery might lead to impaired blood supply to the osteotomy site. The present case-control study aimed to evaluate the effect of LCTA on TPLO healing and the occurrence of perioperative complications. The incidence and predisposing factors to LCTA were also investigated. Fourteen cases experiencing LCTA were retrospectively enrolled from medical records of two veterinary teaching hospitals (LCTA group), whereas 28 randomly selected TPLOs that did not experience LCTA were included in the control group. Signalment data, proximal tibial epiphysis conformation, osteotomy features, perioperative complications, and bone healing were compared between the two groups. Bone healing was evaluated using the modified radiographic union scale for tibial fracture and the visual analog scale. The mean incidence was 9.6%. Bodyweight was significantly higher in the LCTA group compared to the control group (P = 0.009). Dogs belonging to the LCTA groups were significantly younger (P = 0.01). Intraoperative hypotension was significantly overreported in the LCTA group (P = 0.0001). None of the other variables differed significantly between the two groups. Dogs' size seems to be a predisposing factor, with dogs weighing >15 kg having 22 times more chance of experiencing LCTA. Due to the well-developed collateral blood supply of the canine hindlimb, LCTA and the closure of the cranial tibial artery did not appear to delay the radiographic bone healing or affect the incidence of perioperative complications.

Ex vivo evaluation of the effect of various surgical procedures on blood delivery to the patellar tendon of dogs

OBJECTIVE To determine the effect of arthrotomy alone or in combination with osteotomy of the proximal portion of the tibia on blood delivery to the patellar tendon of dogs. SAMPLE 24 canine cadavers. PROCEDURES One hind limb from each cadaver was assigned to 1 of 4 treatment groups: medial arthrotomy (MA; MA group), lateral arthrotomy (LA; LA group), MA and LA with tibial tuberosity transposition (MALA group), and MA with tibial plateau leveling osteotomy (TPLO; TPLO group). The contralateral hind limb served as the control sample. Contrast solution (barium [33%], India ink [17%], and saline [0.9% NaCl] solution [50%]) was injected through an 8F catheter inserted in the caudal portion of the abdominal aorta. Limbs were radiographed to allow examination of vascular filling. The patella, patellar tendon, and tibial crest were harvested, radiographed to allow examination of tissue vascular filling, and fixed in 4% paraformaldehyde. Vessels perfused with contrast solution were counted in sections obtained from the proximal, middle, and distal regions of each patellar tendon. RESULTS Vessel counts did not differ significantly among the 3 tendon regions. Compared with results for the control group, delivery of contrast solution to the patellar tendon was significantly decreased in the MALA and TPLO groups but was not changed in the MA or LA groups. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that surgical procedures used to treat cranial cruciate injuries (ie, TPLO) and patellar luxation decreased blood delivery to the patellar tendon of canine cadavers, at least acutely.

Combined Z-plasty and phalangeal fillet for reconstruction of a large carpal defect following ablative oncologic surgery

A six-year-old Labrador Retriever was presented for management of a 2 x 2 cm cutaneous mass over the dorsal aspect of the carpus. A fine needle aspirate performed by the referring veterinarian was consistent with a mast cell tumour. The ipsilateral prescapular lymph node was enlarged. Preoperative staging did not reveal any evidence of metastasis. Wide excision of the mass and prescapular lymphadenectomy were performed. The large carpal wound was reconstructed using a combination of Z-plasty and phalangeal fillet using the first digit (dewclaw); about 20% of the original defect was allowed to heal by second intention. Histopathology was consistent with a grade II mast cell tumour with metastatic spread to the lymph node. Vinblastine and prednisolone adjuvant chemotherapy was instituted. Functional and cosmetic outcome were good; only a small 1cm area of alopecia persisted. The dog was disease-free 53 months after surgery. A combination of Z-plasty and a phalangeal fillet using the first digit was a successful treatment to reconstruct a large wound over the dorsal aspect of the carpus in this case.

Repair of a canine forelimb skin deficit by microvascular transfer of a caudal superficial epigastric flap

Extensive skin loss from the forelimb of a Border collie was repaired by a microvascular caudal superficial epigastric flap, with secondary meshing of the flap to increase coverage. The caudal superficial epigastric artery and vein were anastomosed to the brachial artery and vein. End-to-end anastomosis to the brachial artery and vein did not compromise peripheral blood flow, and no flap necrosis was observed after subsequent limited meshing of the flap.

Surgical treatment of an elbow hygroma utilizing microvascular free muscle transfer in a newfoundland

Microvascular free muscle transfer utilizing the rectus abdominis muscle, in combination with a mesh skin graft and transarticular external fixator, were used following the surgical excision of an elbow hygroma in a Newfoundland dog. Postoperatively, the dog did well with minimal complications and has yet to have a recurrence 10 months following surgery. This report describes the utility and successful use of the rectus abdominis free tissue transfer in the surgical correction of a difficult elbow hygroma in the dog.

Rectus Abdominis Free Muscle Flap for Reconstruction in Nine Dogs

OBJECTIVE

To evaluate the clinical use and outcome of a rectus abdominis microvascular free flap for wound closure in dogs.

STUDY DESIGN

Retrospective case series.

ANIMALS

Dogs (n=9) with complex extremity or oral wounds.

METHODS

Medical records (2002-2006) of dogs that had a rectus abdominis free tissue transfer to close an extremity or oral wound were reviewed.

RESULTS

Nine dogs were identified: 5 had distal extremity wounds, 3 had oral palatal defects, and 1 had a large hygroma excised. A rectus abdominis free tissue transfer with a caudal epigastric vascular pedicle was successfully used for management of these wounds. No major complications occurred with the donor site and a good cosmetic and functional outcome occurred in all dogs.

CONCLUSION

The rectus abdominis is a versatile muscle that can be used for reconstructing cutaneous and oral defects with repeatable success.

CLINICAL RELEVANCE

Free tissue transfer of the rectus abdominis muscle is a clinically useful technique for closure of a variety of difficult soft tissue wounds.