Puncture Wounds of the Navicular Bursa in 38 Horses A Retrospective Study

The medical records of 38 horses with puncture wounds of the navicular bursa were reviewed. Only 12 horses had a satisfactory outcome (breeding or riding). Of the remaining 26 horses, 19 were euthanized, five were sold due to persistent severe lameness, one died, and one was lost to long-term follow-up. Different combinations of conservative management prior to surgical debridement and drainage of the navicular bursa were unsuccessful in resolving the condition. Horses that were treated surgically within 1 week of the injury and had a hind leg affected had the best chance of a satisfactory outcome. Additional wound debridement was necessary in 15 horses after initial surgical treatment. The most common complications encountered were navicular bone osteomyelitis and sepsis of the deep digital flexor tendon. Thirteen of 14 horses that had rupture of the deep digital flexor tendon and subluxation of the distal interphalangeal joint had an unsatisfactory outcome. One mare subsequently developed ankylosis of the distal interphalangeal joint and was a useful brood mare. Two horses that had biaxial palmar digital neurectomy because of persistent lameness were later euthanized because of navicular bone fracture and rupture of the deep digital flexor tendon. Results from limited numbers of bacterial cultures and antibiotic sensitivities suggest that penicillin and an aminoglycoside antibiotic should be used as initial antibiotic therapy. Immediate surgical debridement and appropriate antibiotic treatment are recommended as the minimum therapy for penetrating wounds of the navicular bursa in horses.     

Electrosurgical Arthrotomy and Excision of Soft Tissue Masses in the Metacarpophalangeal Joint of the Horse

Electrosurgical arthrotomy and excision of infra-articular soft tissue masses from the metacarpophalangeal joint was performed in 12 horses. In six of the 12 horses, osteochondral fragments from the dorsoproximal aspects of the first phalanx were also removed. The electrosurgical scalpel afforded excellent intraoperative efficacy for arthrotomy and relatively bloodless excision of soft tissue masses without the need for a tourniquet. There were no complications associated with healing in 11 of the 12 horses. A retraction technique that used careful positioning of a Langenbeck periosteal elevator relative to the collateral ligaments provided access to both medial and lateral margins of intra-articular masses. With this technique, all masses could be removed through one central arthrotomy incision.     

The Effects of Fixation of the Ulna to the Radius in Young Foals

The effects of radioulnar fixation were studied in 21 Quarter horse foals by applying a bone plate to the caudal aspect of the proximal part of the ulna, with screws engaging both the radius and the ulna. The plates were applied at 1 month of age in six foals (group I), 5 months of age in six foals (group II), and 7 months of age in three foals (group III). Six foals underwent sham operations at 1 month of age to serve as controls (group IV). Ulnar dysplasia and elbow subluxation developed in all treated foals. The magnitude of ulnar dysplasia was inversely related to the patient's age at fixation and was accompanied by degenerative joint disease and lameness in foals undergoing fixation at 1 and 5 months of age. Removal of the fixation appliances 16 weeks after implantation in three foals from each of groups I and II failed to reverse the degree of ulnar dysplasia. Although foals undergoing fixation at 7 months of age (group III) were not lame, radiographic evidence of subluxation and subtle degenerative changes in the articular cartilage of the treated elbow did develop. Recommendations for avoidance of radioulnar fixation were developed from these observations.     

Osseous Sequestration in the Horse A Review of 68 Cases

Sixty-eight cases of cortical bone sequestration in 67 equine patients were reviewed with regard to the clinical presentation, method of treatment, and outcome. All lesions were located in skeletal areas with minimal soft tissue coverage, with 53% of them in the metatarsal and metacarpal bones. At the time of admission, 60% of the patients with limb lesions were lame; the majority improved with therapy. After sequestrectomy, there was a trend for surgical wounds which could be managed by primary closure to heal more rapidly (3.8 weeks) than wounds which required second intention healing (6.4 weeks). The appearance of healed wounds, as evaluated by owners, was acceptable in 45 cases. Dissatisfaction with the appearance of the healed wounds in 22 cases suggested a need to address the issue of cosmetic results.     

Retroversion of the Epiglottis as a Complication of Endotracheal Intubation in the Horse A Pilot Study

As part of a study of possible causes of postoperative pulmonary complications of general anesthesia in the horse, lateral cervical radiographs were taken after endotracheal intubation in nine randomly selected horses. The epiglottis was found to be retroverted in three. Subsequently, the effects of epiglottic retroversion during anesthesia on postoperative laryngeal function were investigated experimentally in three horses by fluoroscopy. No untoward sequelae were observed. Prophylaxis and potential adverse effects of this previously unreported complication of endotracheal intubation in the horse are discussed.     

Transsphenoidal Hypophysectomy in the Dog A New Technique

A technique for localizing the canine hypophysis regardless of the shape or size of a dog's skull was evaluated. Using known anatomic landmarks, the approximate location of the hypophysis was estimated, and three small self-threading screws were placed as radiographic markers in the exposed sphenoid bone. A cranial sinus venogram was performed and the hypophysis was outlined by the contrast-filled cavernous sinus. A circular ostectomy was centered over the hypophysis, using the previously placed screws as reference points. The technique was evaluated in eight dogs in a nonsurvival procedure. In seven dogs, hypophysectomy was complete and the ostectomy sites were centered precisely over the hypophysis.     

Fracture of the Supraglenoid Tubercle Treatment and Results in Five Horses

Five horses with fractures of the supraglenoid tubercle (tuber scapulae) were presented from 6 weeks to 1 year after injury. Clinical signs included lameness characterized by a shortened cranial phase of the stride and shoulder muscle atrophy. Radiographically, the fractures differed in the degree of cranioventral displacement of the fragment as well as the extent of joint involvement. Three horses were treated by resection of the fractured tubercle, including one using a new grid approach to the area of the fracture. Two of these horses have returned to athletic activity and one was euthanized due to postoperative infection. One horse with minimal displacement and joint involvement was treated with rest and raced successfully. One horse seen with a fracture of 1 year duration also was treated with rest and was a pasture sound broodmare.     

Physeal Fractures in the Horse:I. Classification and Incidence

Seventy appendicular skeletal physeal fractures in 67 horses were reviewed and classified using the Salter-Harris classification. All the horses were less than 2 years old (mean age at injury 6.2 months). The mean age at injury for pressure physeal fractures (5.2 months) was significantly less (p < .05) than for traction physeal fractures (8.3 months). The majority (67.2%) of the horses were female. Forty-eight (69%) pressure physes and 22 (31%) traction physes were affected. The most common pressure and traction physeal fracture sites were the proximal femoral physis and the proximal ulnar physis, respectively. Sixty-seven physeal fractures were classified: 14 as Type I (20.9%), 42 as Type II (62.7%), six as Type III (8.9%), and five as Type IV (7.5%). Forty-six pressure physeal fractures were classified: six as Type I (13.0%), 30 as Type II (65.2%), five as Type Hi (10.9%), and 5 as Type IV (10.9%).     

Billroth II Gastrojejunostomy in Dogs Stapling Technique and Postoperative Complications

Billroth II gastrojejunostomy was performed with surgical staplers in 6 dogs that were not irradiated and in 11 dogs that subsequently received radiation to the pancreas and proximal part of the duodenum. The dogs were monitored clinically for 135 days and then euthanatized and necropsied. Each gastrojejunostomy site was preserved in formalin and the stomal diameter was measured. No mechanical complications were encountered with the use of surgical staplers and no leakage was observed at the staple closure sites before abdominal closure. All dogs vomited approximately 100 ml of coagulated blood 4 to 8 hours after surgery, and 300 to 400 ml of brown fluid after approximately 24 hours. Vomiting was the most common clinical finding after the first 24 hours. Vomiting was subjectively graded from 1 to 3 with grade 1 representing the least severe problem and grade 3 the most severe. Grade 1 vomiting occurred in 12 of 16 dogs that survived 135 days; in the other four dogs, vomiting was classified as grade 2 or 3. All dogs with grade 1 vomiting had stomal diameters of 1.7 to 2.9 cm (mean, 2.2 ± 0.4 cm standard deviation). Dogs with grade 2 or 3 vomiting had stomal diameters of 2.2 to 4.0 cm (mean, 3.2 ± 0.8 cm standard deviation). The difference was statistically significant (p < 0.005). The percentage of weight gained or lost was recorded for each dog. Two nonirradiated dogs gained body weight, whereas the other nonirradiated dogs and all irradiated dogs lost body weight. The overall mean loss of body weight of dogs with grade 1 vomiting was 16.7 ± 12.0% (± standard deviation), compared with 35.5 ± 6.6% (± standard deviation) for dogs with grade 2 or 3 vomiting; the difference was significant (p < 0.01). Routinely scheduled clinical laboratory test results were within normal limits in nonirradiated dogs. Clinical problems other than vomiting and weight loss were anorexia, gastric dilatation, and diarrhea. One nonirradiated dog died on day 56 after rupture at the gastric stump staple line.     

Partial Equine Lung Resection Using a Stapling Instrument

Four horses (aged 1 to 18 years) with no apparent respiratory or cardiovascular abnormalities underwent thoracotomy and partial resection of a cranial lung lobe. A stapling instrument was used. Pulmonary function testing prior to and 30 days following surgery showed no significant change in inspiratory or expiratory resistance, compliance, or work of breathing. Postoperative complications consisted of a mild pneumothorax in all horses and localized incisional infection in two horses. All horses displayed a temporary decrease in forward motion of the forelimb on the operated side. Postmortem examination was performed 30 days after surgery; pleural thickening and adhesions between the lung and thoracotomy site were found. The excisionai margin of each cranial lobe was straight with slight puckering due to multiple surgical wire staples. Adjacent tissue collapse and compression were confined to an area no greater than 1 cm from the staples. Beyond this compression, the remaining lung at the surgical site was histologically normal. Subsequently, one horse suffering from recurrent episodes of clinical signs attributed to pleuropneumonia underwent left thoracotomy and partial lung resection followed by a right thoracotomy 48 days later. The horse's condition improved postoperatively, and he was able to undergo normal conditioning and racing.