Lag screw and cancellous bone graft fixation of transverse proximal sesamoid bone fractures in horses: 25 cases (1983-1989).

Case records of 25 horses with transverse fractures of the proximal sesamoid bone were reviewed to evaluate the success of treatment. All fractures were repaired by use of lag screw fixation and an autogenous cancellous bone graft because the fracture fragments were considered too large for surgical removal and reconstruction of the suspensory apparatus was necessary. Radiography was performed in all cases, and the fractures were classified into 3 types: (1) proximal midbody fractures, which included all fractures in the proximal aspect of the sesamoid bone that resulted in fragments involving greater than one third but less than one half of the total mass of the sesamoid bone; (2) midbody fractures that divided the bone into 2 equal portions; and (3) distal midbody fractures, which included transverse fractures in the distal aspect of the sesamoid bone that resulted in fragments involving greater than one third but less than one half of the total mass of the sesamoid bone. Of these cases, race records were obtained for 9 Standardbreds and 5 Thoroughbreds. Postoperative performance criteria evaluated were the ability to train and start 1 race, ability to maintain preinjury class of racing, earnings per start, and the number of starts following surgery. In Thoroughbreds, fractures occurred most commonly in the right forelimb; in Standardbreds, the left hind limb was most commonly involved. The midbody fracture was the most common type in both breeds, and the distribution of fracture location within the sesamoid bone was similar for both breeds.(ABSTRACT TRUNCATED AT 250 WORDS)     

Management of comminuted fractures of the proximal phalanx in horses: 64 cases (1983-2001)

OBJECTIVE: To report the outcome of surgical treatment of comminuted fractures of the proximal phalanx in horses. DESIGN: Retrospective study. ANIMALS: 64 horses. PROCEDURE: Medical records and radiographs were reviewed to obtain information regarding signalment, fracture classification, and treatment. Follow-up information was obtained by telephone conversation or evaluation of production records. RESULTS: Thirty-eight horses had moderately comminuted fractures of the proximal phalanx. Two horses were euthanatized immediately. Fractures of the proximal phalanx in 36 horses were repaired with open reduction and internal fixation with a successful outcome in 33 (92%) horses. Reconstruction of the fracture was performed in most horses by use of a long curved incision, transection of the collateral ligament of the metacarpophalangeal or metatarsophalangeal joint, and open exposure of the proximal articular surface of the proximal phalanx. Twenty-six horses had severely comminuted fractures of the proximal phalanx. Six horses were euthanatized immediately. One horse was euthanatized after 9 days of treatment with a cast alone. Severely comminuted fractures of the proximal phalanx in 13 horses were treated with an external skeletal fixation device, and fractures healed in 8 of those horses. Six horses with severely comminuted fractures of the proximal phalanx were treated with transfixation pins incorporated into a fiberglass cast, and fractures healed in 4 horses. CONCLUSIONS AND CLINICAL RELEVANCE: Moderately comminuted fractures of the proximal phalanx can be successfully repaired; however, fractures that are too severe to permit accurate reconstruction of the fragments remain difficult to treat and horses have only a fair prognosis for survival.     

Use of dynamic compression plates for treatment of tibial diaphyseal fractures in foals: nine cases (1980-1987)

The medical records of 9 foals less than 4 months old, with fracture of the tibial diaphysis, were reviewed. Open reduction was accomplished by use of 3 approaches; however, a cranial approach was preferred and was used in 7 foals. Two dynamic compression plates were implanted in all foals except the first of this series. The technique of plate luting was used in 7 foals and appeared to improve the ability of implants to resist failure. Complications after surgery included partial or complete failure of fracture fixation (n = 3 foals), osteomyelitis (n = 2 foals), angular limb deformity (n = 2 foals), minor dehiscence of the surgical wound (n = 3 foals), and mild extensor deficits of the injured limb (n = 4 foals). One foal was euthanatized 12 hours after surgery because of complete loss of fracture fixation. All other foals were discharged 10 to 295 days after surgery. One or both plates were subsequently removed in 7 foals. Follow-up information was obtained 6 to 36 months after discharge. Excellent results were reported for 6 foals, and good or fair results were reported for the remaining 2 foals.     

Use of a bone plate for treatment of middle phalangeal fractures in horses: seven cases (1979-1984)

Four adult horses and 3 foals with middle phalangeal fractures were treated by arthrodesis of the proximal interphalangeal joint, using a bone plate. Six of the 7 horses survived greater than 2 years; 2 of the 6 horses had intermittent lameness after hard work, and 4 horses didn't have evidence of lameness. The use of a bone plate for arthrodesis of the proximal interphalangeal joint was a successful treatment alternative for middle phalangeal fractures in horses.     

Evaluation of hemostatic defects secondary to vascular tumors in dogs: 11 cases (1983-1988)

Two populations of dogs with cutaneous hemangiomas and hemangiosarcomas were evaluated retrospectively. One population consisted of 96 dogs seen at the Veterinary Medical Teaching Hospital at the University of California, Davis. The second population consisted of 116 dogs that had skin biopsy specimens submitted to a private veterinary diagnostic laboratory for histologic diagnosis. Nine dogs from the teaching hospital and 2 dogs, from which samples had been submitted to the veterinary diagnostic laboratory, developed hemostatic defects in association with the tumors. Hemostatic defects included hemorrhage directly from the tumor, thrombocytopenia, hypofibrinogenemia, and findings associated with disseminated intravascular coagulation. Because bleeding during surgery can develop in animals with hemostatic defects, dogs with one or more tumors suspected of being vascular in origin should have platelet numbers and hemostatic analytes evaluated prior to surgery, especially if petechiae or ecchymoses are evident.     

Use of transfixation pin casts to treat adult horses with comminuted phalangeal fractures: 20 cases (1993-2003)

OBJECTIVE: To determine the clinical applications, short and long-term survival, and complications of using transfixation pin casts for treatment of comminuted phalangeal fractures in adult horses. DESIGN: Retrospective case series. ANIMALS: 20 horses. PROCEDURES: Medical records were reviewed to obtain information regarding signalment, fracture location, treatment methods, complications, and short-term survival (discharge from hospital). Long-term follow-up information was obtained via contact with owners or trainers. RESULTS: 12 fractures were in a hind limb, and 8 were in a forelimb. Fourteen fractures occurred in a middle phalanx, and 6 occurred in a proximal phalanx. Eleven fractures were treated with internal fixation combined with transfixation pin casts, and 9 fractures were treated with transfixation pin casts alone. Transfixation pin casts were maintained for a mean of 52 days (median, 49 days; range, 1 to 131 days). Fourteen (70%) horses were discharged from the hospital, whereas 6 (30%) were euthanized during the treatment period. Reasons for euthanasia included secondary fracture of the third metacarpal or metatarsal bone, avascularity of the distal aspect of the limb associated with an open fracture, and displacement of the fracture after transfixation pin cast removal. A significantly greater number of horses was discharged from the hospital when the transfixation pin cast was maintained for > 40 days, compared with those in which the transfixation pin cast was maintained for < 40 days. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that horses should be maintained in a transfixation pin cast for a minimum of 40 days, as this was associated with an increase in short-term survival without an increased risk of catastrophic failure.     

Evaluation of clinicopathologic features, response to treatment, and risk factors associated with idiopathic neutropenia in dogs: 11 cases (1990-2002)

OBJECTIVE: To evaluate the clinicopathologic features, response to treatment, and risk factors associated with idiopathic neutropenia in dogs. DESIGN: Retrospective case series. ANIMALS: 11 dogs. PROCEDURES: Medical records of dogs with idiopathic neutropenia were reviewed. Signalment, history, clinical signs, and response to treatment were recorded and compared with that in dogs with neutropenia attributable to known causes and to dogs without neutropenia (controls). RESULTS: Compared with dogs with neutropenia attributable to known causes, dogs with idiopathic neutropenia had lower neutrophil counts and were younger. When compared with control dogs, age < 4 years was identified as a risk factor for developing idiopathic neutropenia. In all dogs with idiopathic neutropenia, remission of neutropenia occurred within 18 days after administration of prednisone (2 to 4 mg/kg [0.9 to 1.8 mg/lb], PO, daily) and no serious complications or infections developed. CONCLUSIONS AND CLINICAL RELEVANCE: An immune-mediated pathogenesis should be considered for dogs with idiopathic neutropenia in which the cause is not known. Severe neutropenia and young age were significantly associated with idiopathic neutropenia in dogs. Prognosis appeared to be excellent with prednisone treatment.