Viability of split-thickness skin grafts attached with fibrin glue.

Full-thickness, circular, cutaneous wounds (4 cm diameter) were created on metacarpi and metatarsi of 5 horses. On day 6, all 4 wounds on each horse received a stored autogenous split-thickness sheet graft. Grafts were obtained from the horse's ventrolateral thorax with a pneumatic dermatome at the time the cutaneous wounds were created. Grafts were coapted to the granulation bed of 2 wounds of each horse with fibrin glue. Grafts were coapted to the cutaneous margin of all 4 wounds of each horse with cyanoacrylate glue. Bandages were changed daily until the study ended at 14 d. When the bandages were changed, ointment containing neomycin, polymyxin B, and bacitracin was applied to all wounds. The viable area of graft was measured on post-grafting d 14 and calculated with a micro-processor. Split-thickness sheet-grafts attached to granulation beds on the metacarpi and metatarsi with fibrin glue had no greater survival than did grafts attached without fibrin glue (P > 0.05).

Arthroscopy of the coxofemoral joint of foals.

An arthroscopic procedure for examination of the coxofemoral joint was developed in nine foals (four cadavers, five anesthetized) to determine if access was sufficient for evaluation and surgical treatment of intra-articular lesions. The joint was distended and the arthroscope inserted through the notch (incisura trochanterica) between the cranial and caudal parts of the greater trochanter. This portal allowed examination of the cranial, lateral, and caudal aspects of the joint. Mechanical distraction of the joint through an instrument portal located 2 to 4 cm cranial and 1 to 2 cm ventral to the arthroscope portal allowed examination of the ligament of the head of the femur, the femoral head, and articular and nonarticular surfaces of the acetabulum. Adduction and rotation of the limb improved visualization of the craniomedial and caudomedial portions of the femoral head. Traction applied to the distal limb allowed visualization of the same structures that were observed when mechanical distraction was used. Traction also created space for placement of surgical instruments into the joint through the instrument portal. Access to most regions of the joint was adequate, but access to the caudal and medial aspects of the joint was limited. Three foals were killed while they were anesthetized, and their coxofemoral joints were dissected. Two foals were allowed to recover from anesthesia and were observed for 30 days after surgery. One foal was mildly lame for 2 days after surgery. The other foal was not lame after surgery. The incisions healed, and the coxofemoral joints were radiographically normal by postoperative day 30.

Communication of the ulnaris lateralis bursa with the equine elbow joint and evaluation of caudal arthrocentesis.

Elbows from cadaver limbs were evaluated to determine the presence of a communication between the ulnaris lateralis bursa (ULB) and the joint and the extent of the bursa. Thirty-two pairs of joints were studied: 12 pairs were frozen, then transversely sectioned and 20 pairs were injected with methyl methacrylate. The 12 frozen-section pairs revealed a communication between the ULB and the elbow joint in 9/24 joints (37.5%) and a true bursa (absence of communication) in 15/24 joints (62.5%). The mean bursal length in adult horses was 3.8 cm. There was no significant difference in the length of the bursa or presence of bursa-joint communication between the right and left limbs. In the acrylic specimens a communication between the ULB and the joint was found in 19/40 specimens (47.5%). There was no significant correlation between age or sex and frequency of communication. There was a significantly greater prevalence of communications present in Quarter Horse than in non-Quarter Horse (P < 0.05) joints. A communication between the ULB and the joint is not always present, and therefore injection of the elbow joint via the ULB may be unreliable.

Segmental ischemic necrosis of the small intestine in two postparturient mares.

Two mares developed segmental ischemic necrosis of the small intestine after parturition. In one mare, the mesentery of the small intestine apparently tore during parturition, after which necrosis developed in a 52-cm segment of the distal portion of jejunum. In the other mare, a 52-cm segment of the proximal portion of ileum tore during parturition. Three weeks later, a 40-cm segment of the distal portion of jejunum became incarcerated in the mesenteric rent and twisted 360 degrees on its mesentery. Both mares recovered after resection of affected intestine and are functioning as broodmares.

Effects of split-thickness and full-thickness skin grafts on secondary graft contraction in horses.

Full-thickness, circular (4-cm diameter) cutaneous wounds were created on the metacarpi and metatarsi of 6 horses. Immediately after wounding, 1 wound on each horse received a meshed, split-thickness skin graft (0.64 mm) obtained from the ventrolateral aspect of the horse's thorax by use of a pneumatic dermatome, whereas a second wound received a meshed, full-thickness skin graft obtained from the pectoral area. In addition, sections of split-thickness and full-thickness grafts were refrigerated in a solution of McCoy's 5A medium, to which equine serum (10%) and gentamicin sulfate solution (16 mg/dl) were added. Ten days after wounding, 1 granulating wound on each horse was grafted with a stored, meshed, split-thickness graft, and 1 granulating wound on each horse was grafted with a stored, meshed, full-thickness graft. Areas of wounds were calculated from photographs taken of wounds on days 1, 5, 10, 15, 20, 25, and 30 after wounding. Time course of contraction was determined by use of a first-order mathematic model of changes in area through time. Rate constants of contraction for fresh or granulating wounds receiving full-thickness grafts did not differ significantly from those for fresh or granulating wounds receiving split-thickness grafts. Rate constants of contraction for grafted fresh wounds, however, were significantly less than those of grafted granulating wounds, regardless of whether a split-thickness or full-thickness graft was applied.

Communication between the femoropatellar and medial and lateral femorotibial joints in horses.

Communications between the femoropatellar, medial femorotibial, and lateral femorotibial joints were studied, using fresh equine cadaver specimens. A total of 90 specimens from 45 horses were used. Horses were randomly assigned to 3 groups with 15 horses/group. Each group was assigned an injection site (femoropatellar joint, medial femorotibial joint, or lateral femorotibial joint), and red latex was injected into the respective location of each joint in each group. Immediately after injection, the joints were flexed and extended 100 times. The stifles were frozen in slight flexion, then cut into 1-cm sagittal sections. The communications between the femoropatellar and medial and lateral femorotibial joints were determined. None of the specimens in this study had communication between all 3 joint compartments. When the femoropatellar joint was injected, 18 of 30 joints (60%) communicated with the medial femorotibial joint, and 1 of 30 (3%) communicated with the lateral femorotibial joint. Injection of the medial femorotibial joint revealed 24 of 30 (80%) joints that communicated with the femoropatellar joint, and 1 of 30 (3%) that communicated with the lateral femorotibial joint. Injection of the lateral femorotibial joint resulted in communication with the femoropatellar joint in 1 of 30 (3%) joints. Communication did not exist between the medial and lateral femorotibial joints.

Septic arthritis of the distal interphalangeal joint in 12 horses.

The medical records of 12 horses with septic arthritis of a distal interphalangeal joint were reviewed to determine clinical features and response to treatment. Sepsis was caused by trauma or an injection that resulted in an open or contaminated distal interphalangeal joint. All horses were severely lame. Treatment included broad-spectrum parenterally administered antimicrobial drugs (ten horses), percutaneous through-and-through joint lavage (eight horses), indwelling drains (three horses), immobilization of the limb in a cast (three horses), intraarticular injection of sodium hyaluronate (one horse), intraarticular injection of antimicrobial drugs (five horses), curettage of the distal phalanx (one horse), and cancellous bone grafting to promote fusion (one horse). Five horses were euthanatized. Ankylosis of the affected joint developed in five horses, four of which are pasture sound. Two horses treated medically are sound although one underwent subsequent palmar digital neurectomy for treatment of navicular syndrome.

Standing surgery and procedures of the head.

Although most surgical procedures of the head are technically easier to perform with the horse under general anesthesia, other factors will influence whether a surgical procedure is performed with the horse standing or recumbent under the influence of general anesthesia. The accessibility of the head lends itself to many standing surgical procedures if the proper combination of analgesia and physical and chemical restraint is used. Traumatic injuries of the head (lacerations, facial bone fractures, and oral fractures) may involve vital structures, and a thorough examination is indicated. Failure to treat a traumatic injury may result in facial deformity, bony sequestra, paranasal sinusitis, salivary-cutaneous fistula, cutaneous fistulas into a nasal passage or paranasal sinus, nasal septal deformities, and ocular dysfunction. Proper management of these injuries typically results in a cosmetic outcome because of the head's abundant blood supply. Other surgical procedures that can be performed in the standing horse include centesis and trephination of the paranasal sinuses, certain dental procedures, alar fold stabilization, and extirpation of epidermal inclusion cysts of the nasal diverticulum.

Surgical repair of an intrathoracic esophageal pulsion diverticulum in a horse.

An intrathoracic esophageal pulsion diverticulum causing repeated episodes of esophageal obstruction in a Morgan weanling colt was diagnosed by endoscopy, positive contrast radiography, and pleuroscopy. Surgical excision of the diverticulum alleviated clinical signs, and the horse was able to resume a normal diet by day 6. After 9 months the colt remains asymptomatic.

Ileocecal intussusception in horses: 26 cases (1981-1988).

The case records of 26 horses with ileocecal intussusception over a 7-year period were reviewed to determine clinical features of the disease and response to treatment. The median age of horses with ileocecal intussusception was 1 year and ranged from 2 weeks to 19 years. There was no apparent gender or breed predisposition to this disease. An acute form of ileocecal intussusception was diagnosed in 19 horses with signs of moderate to severe abdominal pain of less than or equal to 24 hours' duration, and a chronic form was diagnosed in 7 horses with signs of intermittent, mild to moderate abdominal pain of more than 3 days' duration. Horses with chronic ileocecal intussusception had a history of weight loss or failure to gain weight, slow growth, poor appetite, low-grade pyrexia, and postprandial signs of abdominal pain. At surgery, the involved segments of intestine (intussusceptum and intussuscipiens) in chronic cases were 2 to 10 cm long, and the ileum and much of the distal portion of the jejunum were flaccid, dilated, and thick walled. In the acute cases, the length of involved intestine ranged from 6 to 457 cm. Whereas only 1 of 7 chronic intussusceptions (14%) could be reduced, 9 of 19 (47%) acute intussusceptions were reducible. Surgical treatment included resection and jejunocecostomy (6 horses), partial resection through a cecotomy and a side-to-side jejunocecostomy (2 horses), and a side-to-side ileocecostomy or jejunocecostomy without resection (12 horses, 7 of which had chronic intussusception). Six horses with acute intussusception were euthanatized before or during surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary teat neoplasia in two yearling heifers.

Two yearling heifers developed rapidly growing soft tissue masses attached to the base of the right hind teat. In each heifer, the solitary mass was raised, firm, and attached to the overlying skin. En bloc removal was accomplished in each by positioning the heifer in dorsal recumbency and by using local infiltration analgesia. Histologic examination revealed one of the masses to be fibroma and the other, fibrosarcoma. Neither tumor has recurred, and normal function of the teat was retained.

Surgical management of duodenal obstruction in an adult horse.

A 3-year-old Standardbred stallion was admitted for treatment of acute enterocolitis. The horse improved in response to empiric treatment, but subsequently developed ventral edema, scrotal abscessation, and severe laminitis. Improvement again was seen, but on day 29 of hospitalization, the horse developed rapid heart rate and signs of abdominal pain. Exploratory celiotomy revealed complete obstruction of the descending portion of the duodenum, 20 cm caudal to the duodenal sigmoidal flexure. Three-tier duodenojejunostomy and jejunojejunostomy were performed to bypass the duodenal obstruction.

Osteochondral fragments within the dorsal pouch or dorsal joint capsule of the proximal intertarsal joint of the horse.

The anatomy of the dorsal pouch of the proximal intertarsal joint (PIJ) and its communication with the tarsocrural joint (TCJ) was studied in 15 pairs of hocks from young and mature horses. The mediolateral length of the TCJ-PIJ fenestration was 14 to 29 mm. The potential volume of the dorsal pouch of the PIJ was 3 to 5 ml, and a recess extended 10 to 28 mm medial to the medial commissure of the TCJ-PIJ fenestration. In a correlated clinical study, osteochondral fragments were identified radiographically within the dorsal pouch (category 1) or dorsal joint capsule (category 2) of the PIJ in 17 horses undergoing arthroscopic surgery of the TCJ. In six horses with category 1 lesions, osteochondral fragments were found free within the dorsal pouch and were removed. In five horses, category 1 fragments were not located. All 11 horses were reported by owners to be sound after surgery. In seven horses, a minimally displaced fragment was identified at the distal aspect of the medial trochlear ridge, within the insertion of the synovium separating TCJ and PIJ (one horse had both types of lesions in the same hock). Five of the seven category 2 fragments were removed at surgery. Of the seven horses with category 2 lesions, four were training or racing, two were unsound, and one was still convalescing at the time of follow-up.

A comparison of methods for proximal palmar metacarpal analgesia in horses.

Three techniques for inducing analgesia of the proximal metacarpal region were evaluated for the frequency of inadvertent injection into the middle carpal and carpometacarpal joints. Using methylene blue solution as a marker dye and 30 fresh cadaver specimens each, three clinicians performed either 30 infiltrations at the origin of the suspensory ligament (method A), 30 palmar and palmar metacarpal nerve blocks at the proximal end of the metacarpus (method B), or 30 palmar and palmar metacarpal nerve blocks at the distal aspect of the accessory carpal bone (method C). The frequency of inadvertent injection into the distal carpal joints was 37, 17, and 0% for methods A, B, and C, respectively. The association between method and injection into the joints was significant (p less than 0.01). Infiltration of the distal carpal joints occurred with injection distances from the carpometacarpal joint of 1.5 to 4.5 cm. Although there was no joint injection with method C, the carpal synovial sheath was inadvertently infiltrated in 68% of the specimens. Injection into the distal carpal joints can occur when deep injections are made into the proximal palmar aspect of the metacarpus because of the distopalmar outpouchings of the carpometacarpal joint between the axial surfaces of the second and fourth metacarpal bones and the abaxial surface of the suspensory ligament.

Communications and boundaries of the middle carpal and carpometacarpal joints in horses.

To study communications and boundaries of the middle carpal and carpometacarpal joints of the horse, 50 forelimbs were obtained from fresh cadaver specimens. Blue latex solution (20 +/- 2.5 ml) was injected into the middle carpal joint, and the specimens were frozen in extension. Frozen specimens were cut into 1-cm sagittal sections from the middle of the radius to the middle of the metacarpus. The communications between the middle carpal and carpometacarpal joints and the presence, length, and position of the distopalmar outpouchings of the carpometacarpal joint were recorded. The middle carpal and carpometacarpal joints always communicated between os carpale III (C3) and os carpale IV (C4). An additional communication between the joints existed in 17 (34%) of the specimens, 10 on the palmar aspect of C4, and 3 on the palmar aspect of os carpale II (C2). When os carpale I (C1) was present (n = 5), communication between C1 and C2 was observed in 4 of the 5 specimens. In all specimens, medial and lateral distopalmar outpouchings of the carpometacarpal joint were observed and were located between the axial surface of os metacarpale II (MC2) and os metacarpale IV (MC4) and the abaxial surface of the suspensory ligament. There was no significant difference between the lengths of the lateral (2.3 +/- 0.54 cm) or medial (2.6 +/- 0.75 cm) distopalmar outpouchings. Small extensions from the distopalmar outpouchings were seen and extended axially into the fibers of the suspensory ligament or between the suspensory ligament and the distal accessory ligament of the deep digital flexor tendon.(ABSTRACT TRUNCATED AT 250 WORDS)

Incomplete longitudinal fracture of the proximal palmar cortex of the third metacarpal bone in horses.

Seven horses, 2 to 4 years of age, were examined because of moderate-to-severe forelimb lameness, mild effusion of the middle carpal joint (3 horses), and pain on palpation of the origin of the suspensory ligament (4 horses). The lameness was abolished by anesthetic infiltration of the middle carpal joint in six horses. In four of them, a high palmar nerve block also abolished the lameness. A linear radiolucency in the proximal end of the third metacarpal bone (McIII) was interpreted as an incomplete longitudinal fracture. In one horse, distinct intramedullary sclerosis limited to the palmar cortex was indicative of an incomplete fracture confined to the palmar cortex. No osteoproliferative lesions were identified on the dorsal cortex of any of the horses. Surgical treatment with cortical screws in lag fashion accompanied by a rest period was successful in one horse. In four horses, rest for at least 3 months resulted in clinical soundness. In two horses, a shorter rest period resulted in recurrence of the lameness even though the horses were sound when put back into training. Careful clinical and radiographic examinations helped differentiate incomplete longitudinal fractures from lesions involving the carpus and proximal aspect of the suspensory ligament.

Pleuroscopic diagnosis of gastroesophageal squamous cell carcinoma in a horse.

A 15-year-old Quarter Horse gelding was examined because of chronic intermittent colic of 40 days' duration. The clinical signs included acute onset of depression, ptyalism, abdominal splinting, and rolling within an hour of eating. An intramural mass of the esophagus was identified during esophagoscopy. A large soft-tissue density surrounding the distal portion of the esophagus, creating a stricture, was identified on an esophagogram. With the horse slightly sedated, pleuroscopy was performed, allowing direct visualization and biopsy of the mass. The histopathologic diagnosis was squamous cell carcinoma.

Use of cancellous bone graft in treatment of navicular bone osteomyelitis in a foal.

A 3-month-old Quarter Horse filly stepped on a fence staple and developed navicular bone osteomyelitis of the right hindfoot. A 1.5-cm spherical portion of medullary cavity containing purulent material was debrided and flushed with 0.9% NaCl solution. Cancellous bone was collected from a caudal sternebra and placed into the defect. The solar defect had filled with granulation tissue and was epithelialized 6 weeks after surgery. At 6-month follow-up evaluation, the navicular bone defect had healed and the foal was sound on the limb. Cancellous bone grafting may have merit for the treatment of navicular bone osteomyelitis in the horse.