The Medial Saphenous Fasciocutaneous Free Flap in Dogs

The purpose of this study was to identify the angiosome of the medial saphenous artery and vein and to evaluate the use of this cutaneous angiosome as a free skin flap in the dog. In phase 1 of this study, selective angiography of the medial saphenous artery performed in six canine cadavers showed that the skin covering the entire medial femorotibial area, the distal half of the caudal head of the sartorius muscle, and the gracilis muscle were perfused by the medial saphenous artery. In phase 2, a medial saphenous fasciocutaneous island flap was raised and sutured back to the skin edges of the donor wound in three dogs. One hundred percent survival of all of the flaps occurred. In phase 3, a medial saphenous fasciocutaneous microvascular free flap was transferred to a wound that was created over the dorsal metacarpal (n = 3) or metatarsal region (n = 3). The mean length ± SD of the medial saphenous vascular pedicle was 80 ± 13 mm (n = 5); the mean diameter ± SD of the medial saphenous artery was 2.8 ± 0.2 mm (n = 5) and the mean diameter ± SD of the medial saphenous vein was 4.2 ± 0.2 mm (n = 5). One hundred percent of all flaps survived (n = 6). Selective angiography of the distal cranial tibial artery (metatarsal wounds, n = 3) and the median artery (metacarpal wound, n = 3) was performed 3 weeks after surgery. All of the vascular anastomoses were patent and neovascularization of the wound beds was present. This free flap was found to be acceptable for cosmetic reconstruction of wounds located on the distal extremity.     

Cervical Intervertebral Disk Protrusion in a Horse

A Hansen type ll intervertebral disk protrusion was diagnosed in an 18-year-old horse with signs of progressive ataxia and paresis. A soft tissue mass dorsal to the C6-C7 intervertebral disk space was identified at myelogram and found to be an intervertebral disk protrusion with enlarged dorsal annulus fibrosis at surgery. Surgical decompression was achieved using a ventral approach to the caudal cervical vertebrae, an approach limited in its application by the vertebral venous sinuses. Neurological signs remained unchanged for 3 days and then deteriorated. The horse was euthanized.     

MAGNETIC RESONANCE IMAGING OF THE NORMAL EQUINE DIGIT AND METACARPOPHALANGEAL JOINT

Magnetic resonance (MR) images were made in sagittal and transverse planes through the metacarpophalangeal joint and digit of a horse. The images accurately depicted gross anatomic structures in the leg. Soft tissue structures were defined as separate entities on the images. Histologic varlation in tissues correlated with signal intensity differences on the MR images. Magnetic resonance imaging appears to be a promising imaging modality for evaluating musculoskeletal structures in equine limbs.     

Significance of the Heineke-Mikulicz Pyloroplasty in the Treatment of Gastric Dilatation-Volvulus A Prospective Clinical Study

Twenty-six dogs with gastric dilatation-volvulus (GDV) were stabilized medically, followed by tube gastrostomy and gastropexy. In 13 dogs, a Heineke-Mikulicz pyloroplasty was also performed. Complications and recurrences were monitored during the immediate postoperative period and for 5 to 31 months thereafter. Barium gastrograms and contrast radiographs of the stomach were evaluated at week 1 and months 5 to 31. Significantly fewer dogs without pyloroplasty had complications during the immediate postoperative period. There were no differences in the long-term complication rates. Radiographic evaluations of the width of the pylorus, the size of the stomach, and the rate of gastric emptying showed no differences between dogs with and without pyloroplasty at any evaluation period. The Heineke-Mikulicz pyloroplasty increased the immediate postoperative complication rate after surgical fixation of the stomach for the treatment of GDV. It did not appear to influence the long-term outcome of the surgical treatment of this disease. The Heineke-Mikulicz pyloroplasty is not recommended in the treatment of GDV unless pyloric outflow obstruction can be demonstrated.     

Clinical and Pathologic Effects of a Modified Technique for Application of Spiral Prostheses to the Cervical Trachea of Dogs

A modified surgical technique for application of extraluminal polypropylene spiral prostheses (PSP) to the trachea was developed. A portion of the segmental blood supply to the collapsed segment of trachea was maintained by fenestrating rather than completely dissecting the right lateral pedicle. Polypropylene spiral prostheses were applied to the cervical trachea of 12 dogs (group I) via the modified technique and to 12 dogs (group II) with the identical surgical dissection but without PSP applied. Clinical abnormalities included mild coughing in group I dogs and swelling of the incisions in both groups. Limited necrosis and moderate degeneration and inflammation were observed histologically in both groups. Pathologic changes were worse in the caudal cervical segment of the trachea. Mucosal regeneration was present on day 10 in both groups. Transmural tracheal necrosis was not observed. The modified technique for application of PSP is recommended by the authors because it provides adequate surgical exposure and the blood supply preserved by segmentally dissecting the right lateral pedicle is adequate to maintain tracheal viability.     

Quantitative Ingrowth Analysis of a Porous-coated Acetabular Component in a Canine Model

Histomorphometric analysis of bone ingrowth into a porous-coated acetabular component was evaluated in a canine model. A total of nine prostheses were evaluated, 3 at 6 months, 3 at 12 months, and 3 at 24 months after implantation. All implants were grossly stable at the time of retrieval. The mean percentage of bone ingrowth was 12% at 6 months, 24% at 12 months, and 24% at 24 months. Narrow radiolucent lines noted on microradiographs were more evident at the 6 month time period than at the 12 or 24 month time periods. Bone ingrowth into a porous-coated acetabular component in a weight-bearing model may continue beyond the 6 month time period, and early evaluation of bone ingrowth may underestimate final bone ingrowth.     

Palmar Digital Neurectomy in Horses 57 Cases (1984–1990)

The medical records of 57 horses that had palmar digital neurectomy performed between 1984 and 1990 were reviewed. Neurectomies were performed either by transection and elec-trocoagulation (47 horses) or by the guillotine technique (10 horses). Middle-aged geldings, Quarter Horses, and Thoroughbreds were significantly over-represented when compared with the hospital population. Horses used as hunter/jumpers also appeared to be over-represented. Complications occurred in 17 (34%) of the 50 horses for which follow-up information was obtained. Recurrence of heel pain was the most common complication (14 horses). Palpable painful neuromas were detected in three horses. One year after neurectomy, 74% of the horses were sound; this decreased to 63% after 2 years.     

Results of Craniotomy for the Treatment of Cerebral Meningioma in 42 Cats

Forty-two cats underwent craniotomy for removal of a meningioma between 1985 and 1991. Median duration of clinical signs before examination was 1.25 months. All cats had inappropriate demeanor: 48% were dull and 38% were lethargic. Neurological deficits included impaired vision in 93%, paresis in 83%, and seizures in 19%. Computed tomography (CT) showed solitary masses in 86% and multiple masses in 14%. Intraoperative complications included hemorrhage and difficulty excising deep or adherent masses. Anemia in 13 of 42 cats was the most common immediate postoperative complication. Ten of 42 cats had no improvement or a more severe neurological status after surgery. Eight of 42 cats died immediately after surgery; 6 of these were anemic. Of the cats that survived the immediate postoperative period, evaluation 10 to 14 days after surgery showed that 97% (33 of 34) were alert and 79% (27 of 34) had returned to normal behavior. Neurological deficits, except for vision impairment, had resolved in most cats. The duration of follow-up varied from 1.3 months to 55.1 months. Ten cats developed neurological abnormalities from 1 month to 44.2 months after surgery; of these, 6 had tumor recurrence or new growth confirmed by CT scan or necropsy. Overall survival was 71% at 6 months, 66% at 1 year, and 50% at 2 years. Age of cat and location of tumor did not significantly affect survival ( P = . 1034 and .1851, respectively). There were too few precise measurements of tumor size to make a valid statistical comparison of the effect of size on survival. Location or presence of multiple tumors did not affect final outcome. Results of this study indicate that surgical excision is a beneficial method of treatment of cranial meningioma in cats.     

Long-Term Results of Complete and Partial Ligation of Congenital Portosystemic Shunts in Dogs

The medical records of 65 dogs that underwent complete or partial ligation of a single congenital portosystemic shunt (CPSS) were reviewed to determine the long-term clinical results. Information retrieved from the records included age at surgery, preligation (baseline) portal pressure, postligation portal pressure, change in portal pressure from baseline, complete or partial occlusion of the shunting vessel and fasting, and 2-hour postprandial bile acids from the preoperative, early postoperative (PO), and greater than 1 year PO time periods. A clinical rating score derived from a follow-up examination greater than 1 year PO was assigned to each dog. Of the 56 dogs that survived the perioperative period, 29 (52%) had complete and 27 (48%) had partial ligations. Age at surgery, pre- and postligation portal pressure, change in portal pressure from baseline and serum bile acid concentrations were not related to long-term clinical outcome. Clinical rating scores were significantly greater for dogs with partial CPSS ligations compared with dogs with complete ligations, indicating a less favorable clinical outcome for partial ligations. Fasting and 2-hour postprandial bile acid values at both PO time intervals were significantly greater in partial versus complete ligation groups. Follow-up information for more than 1 year was available on 18 of 29 dogs (62%) with complete ligations. All were clinically normal. Of 27 dogs with partial ligations, 11 dogs (41%) developed recurrence of clinical signs resulting in presentation to the university or referring veterinarian for additional surgery, medical management, or euthanasia. Only three dogs with partial CPSS ligation (11%) were clinically normal. Another nine dogs (33%) were operated on again before the possible development of clinical signs and four dogs (15%) were unavailable for follow-up. It was concluded that partial ligation of CPSS is associated with a greater recurrance of clinical signs and patient morbidity than complete ligation.