Internal Skeletal Fixation Using a Kirschner Apparatus for Stabilization of Fracture/Luxations of the Lumbosacral Joint in Six Dogs: A Modification of the Transilial Pin Technique

A technique using a modification of the transilial pin technique for stabilization of fracture/ luxations of the lumbosacral joint was performed in six dogs. This technique used an internal skeletal fixator composed of two transilial pins secured with two double fixator clamps. Collapse (shortening) of the seventh lumbar vertebra (L7) was observed in five dogs without compromise of the vertebral canal. Kirschner wires placed across the articular facets as supplemental fixation devices migrated to the subcutaneous tissues in two dogs and were easily removed. Migration of the internal fixators was not observed during healing; vertebral canal dimensions were maintained in all cases, and the internal fixators were not removed after resolution of fracture healing. All fractures were healed within 6 to 12 weeks of surgery without evidence of pain, neurologic impairment, or long-term complications.     

Usefulness of hemilaminectomy for cervical intervertebral disk disease in small dogs

Hemilaminectomy was performed to treat cervical disc disease in 18 small dogs. Cervical spinal cord compression was characterized by ventral and/or lateral compression on myelograms. The duration of follow-up examinations ranged from 2 to 72 months. The optimal response time after surgery ranged from 2 days to 3 months. The outcome was determined to be excellent if clinical signs resolved and the dog had completely improved. The outcome was determined to be good if the dog improved, but was not clinically normal or if the degree of the owner's satisfaction was insufficient. Fourteen dogs achieved complete neurologic recovery without complications. One dog was initially neurologically worse after surgery, but ultimately improved to normal neurologic status. These outcomes were judged to be excellent. In the remaining 3 dogs, 2 dogs had relapse of neck pain and one dog remained mildly ataxic. These outcomes were judged to be good. These results suggest that hemilaminectomy is an effective option for surgical treatment of spinal cord compression secondary to cervical disc disease in small dogs.     

Ureterocolonic anastomosis in clinically normal dogs

Ureterocolonic anastomosis was evaluated in 13 clinically normal dogs. Urinary continence was maintained after surgery, and the procedure was completed without technique errors in all but 2 dogs. Three dogs died within 5 weeks (2 of undetermined causes and 1 of aspiration pneumonia and neurologic disease), and 1 dog was euthanatized 4 months after surgery because of neurologic signs. Two healthy dogs were euthanatized 3 months after surgery for light microscopic evaluation of their kidneys. Five dogs were euthanatized 6 months after surgery for light microscopic evaluation of their kidneys. Gastrointestinal and neurologic disturbances developed in 4 dogs at various postoperative intervals. Plasma ammonia concentration measured in 2 dogs with neurologic signs was increased. Plasma ammonia concentration measured in 5 dogs without neurologic signs was within normal limits. All 5 dogs, in which metabolic acidosis was diagnosed, had high normal or above normal serum chloride concentration. Serum urea nitrogen values were increased after surgery because of colonic absorption of urea. Serum creatinine concentration was increased in 1 dog 6 months after surgery. Individual kidney glomerular filtration rate was reduced in 38% (3/8) of the kidneys from 4 other dogs at 6 months after surgery. Of 5 dogs euthanatized at 3 to 4 months after surgery, 4 had bilateral pyelitis, and 1 had unilateral pyelonephritis. Six months after surgery, pyelonephritis was diagnosed in 40% (4/10) of the kidneys from 5 dogs. The ureterocolonic anastomosis procedure is a salvage procedure that should allow complete cystectomy. However, variable degrees of metabolic acidosis, hyperammonemia, and neurologic disease may result.     

Syringosubarachnoid shunt as a management for syringohydromyelia in dogs

Objective : To evaluate retrospectively the efficacy of syringosubarachnoid shunt for the management of syringohydromyelia/syringomyelia. Methods : Eleven dogs diagnosed with syringohydromyelia/syringomyelia by magnetic resonance imaging associated with Chiari‐like malformation underwent placement of a syringosubarachnoid shunt at the cervical (nine dogs) or lumbar (two dogs) spinal cord. In one dog, a suboccipital decompression (foramen magnum decompression) was performed 4 months before inserting a syringosubarachnoid shunt. All dogs were evaluated neurologically a few hours after surgery, 2 weeks and 6 months postoperatively. Retrospectively, cases were assigned a preoperative and postoperative pain score. Results : There were no intra‐ or peri‐operative complications. One dog (9%) was euthanased 5 weeks after surgery. Progressive neurological improvement was observed in nine dogs (81·8%) 2 weeks and 6 months postoperatively. No clinical improvement was seen in another dog (9%). One dog (9%) had replacement of the syringosubarachnoid shunt. Seven dogs (63·6%) were still alive 1 to 4 years (mean, 2·6 years) after surgery. Clinical Significance : Placement of a syringosubarachnoid shunt in the presence of a sufficiently large syrinx appears to be beneficial in dogs with Chiari‐like malformation and associated syringohydromyelia/syringomyelia.     

Suspected Spinal Epidural Empyema and Associated Vertebral Osteomyelitis (Physitis)in a Dog

A 1 year old female Aurstralian Heeler dog was presented for fever and paraplegia of recent onset. Radiography and myelography revealed osteolysis of the first lumber (L₁) vertebra and extensive epidural spinal cord compression from the level of the thirteenth thoracic (T₁₃) to the fourth lumbar (L4) vertebra. A decompressive hemilaminectomy was performed; purulent-appearing fluid and inflamed epidural fat were present in the vertebral canal. The neurologic recovery of the dog was satisfactory 6 months following surgery.     

Dicondylar humeral fracture stabilisation in a dog using a transilial rod and external fixation

Repair of a Salter-Harris type IV dicondylar humeral fracture was performed on a 15-week-old pitbull terrier. Interfragmentary compression of the intracondylar component of the fracture was achieved with a transilial rod and locking nuts (Trans-ilial Rod; IMEX Veterinary, Inc.). The transilial rod was articulated with a modified type I external fixator which functioned as adjunctive stabilisation for the supracondylar component of the fracture. Fracture healing was confirmed radiographically five weeks following surgery. The dog had no appreciable lameness when examined 12 months after fracture repair.     

Repair of radial fractures in toy breed dogs with self-reinforced biodegradable bone plates, metal screws, and light-weight external coaptation

OBJECTIVE: To describe a surgical technique for, and outcome after, treatment of radial fractures with biodegradable self-reinforced polylactide plates and metal screws, and external coaptation. STUDY DESIGN: Prospective clinical study. SAMPLE POPULATION: Eleven Toy breed dogs. METHODS: Radial fractures were repaired by application of a single or 2 stacked biodegradable self-reinforced polylactide plates (poly-L/D, L-lactide, stereocopolymer [LL-and DL-lactide ratio 70/30]; SR-PLA (70/30) implants) secured with metal screws, and light-weight external coaptation. Healing was evaluated clinically and by radiography at 2, 4, 6, 8, 9, 12, 24-26 weeks, and at 1 and 2 years. Owners were interviewed 3 years after surgery. RESULTS: Radial fracture lines disappeared within 4-14 weeks in 10 dogs; an implant failed in 1 dog. Ambulation was excellent for healed fractures. Excessive skin tension led to removal of implants in 1 dog and suture repair in another dog. No foreign body reaction from implant degradation was observed and the plate was usually no longer palpable at 2 years. One dog had a fracture through a screw hole at 1 year. CONCLUSION: Healing and complication rates after repair of radial fractures with SR-PLA (70/30) plates were considered similar or better than reported after repair with metallic plates or external fixation in Toy breed dogs. No radiographic signs of osteopenia were identified under the plate during follow-up. CLINICAL RELEVANCE: Biodegradable polylactide plates could be considered as an alternative to metal plates for radial fracture repair in Toy breed dogs, however available plates are likely not strong enough when used as a single plate. Implant removal is usually not needed.     

Surgical excision of ectopic thyroid carcinoma involving the base of the tongue in dogs: three cases (1980-1987)

Localized thyroid carcinoma involving the base of the tongue was diagnosed in 3 dogs examined because of a midline cervical mass rostroventral to the larynx. These masses had been present for 4 to 12 months and were firm, nonsensitive, and fixed in position. One dog had progressive dysphagia and dyspnea. Masses were surgically excised together with the base of the tongue and portions of the hyoid apparatus. Severe dyspnea that developed immediately after surgery in 1 dog was managed by tracheostomy intubation for 4 days. Transient dysphagia developed in all dogs. Hydration was maintained by IV fluid administration until water and food of gruel consistency could be swallowed 1 to 6 days after surgery. Consistency of food was gradually thickened to normal, as swallowing improved 6 days to 2 months after surgery. One dog developed aspiration pneumonia that resolved after antimicrobial administration and improved swallowing that prevented further aspiration. After 9 months, 3 years, and 6 years, the dogs were clinically normal.     

Suspected paraspinal abscess and spinal epidural empyema in a dog

Epidural spinal cord compression was visualized myelographically in a dog presented for rapid development of paraparesis. A large, fluid-filled pocket in the epaxial musculature was found at surgery and appeared to communicate with the first lumbar vertebra. Unfortunately, cytopathological evaluation of the fluid was not performed. No etiological agents were isolated on aerobic culture. The dog responded well to decompressive surgery and medical therapy consisting of antibiotics, pain medication, and nursing care. In the veterinary literature, only two studies of spinal epidural empyema in the dog have been reported. Of these dogs, one had successful decompressive surgery performed. The other dogs in these two reports were euthanized. The dog presented in this report fully recovered. Spinal epidural empyema should be considered as a differential diagnosis in dogs presenting with a fever and a rapidly progressing myelopathy.     

Signs consistent with syringobulbia may be detected in dogs undergoing MRI

Syringobulbia is a pathologic condition characterized by one or more fluid‐filled cavities within the brainstem. This retrospective case series describes observations in eight dogs with syringobulbia diagnosed during MRI. All dogs were adult, small‐breed dogs with concurrent syringomyelia and neurologic deficits localized to sites rostral to the spinal cord, which cannot be explained by syringomyelia (eg, six dogs had vestibular signs). On MRI, the fluid‐filled cavities had signal intensity characteristics like cerebrospinal fluid, were in the medulla oblongata, and were solitary in each dog. Initially, the shape of the cavity was a slit in five dogs and bulbous in two dogs. Magnetic resonance imaging was repeated in five dogs (6‐55 months of age). One dog had progression of syringobulbia from slit‐like to bulbous, and four dogs had unchanged slit‐like syringobulbia. One dog developed slit‐like syringobulbia after cranioplasty. A variety of medical and surgical treatments were performed with improvement of some but not all clinical signs. One dog died following surgery due to cardiopulmonary failure and the other seven dogs were alive at least 1 year after the initial diagnosis, which was the least time of follow‐up. One surviving dog developed a unilateral hypoglossal nerve deficit 2 months after the initial diagnosis and megaesophagus 14 months later. In conclusion, detecting a fluid‐filled cavity in the medulla oblongata consistent with syringobulbia is possible in dogs undergoing MRI. The cavity is likely acquired, slit‐like or bulbous, progressive, or static, and might be associated with breed size and neurologic signs localized to the medulla oblongata.     

Surgical Treatment of Pheochromocytoma: Technique, Complications, and Results in Six Dogs

Six dogs were diagnosed with phcochromocyloma and staged according to the World Health Organization's system for tumor classification. Two dogs had benign tumors (Tl, NO, M0) and four dogs had malignant tumors (T2, NO. M 1 or T3, N0, M0). All dogs had adrenalectomy, two dogs had concurrent nephrectomy, and three dogs had concurrent resection of a tumor thrombus from the vena cava. Anesthetic complications occurred in five dogs, including wide variations in heart rate (four dogs), blood pressure (five dogs), and cardiac arrythmias (one dog). One dog died 12 hours after surgery from partial dehiscence of the suture line and hemorrhage from the vena cava, and one dog died 6 days after surgery during general anesthesia for treatment of laryngeal paralysis. Four dogs survived from 3 to 23 months (median, 15 months). One dog remained hypertensive after surgery. Benign and malignant pheochromocytomas seem to be amenable to surgical resection. © Copyright 1994 by The American College of Veterinary Surgeons     

Evaluation of techniques and outcomes of mitral valve repair in dogs

OBJECTIVE: To describe surgical techniques for and assess outcome of treatment of mitral regurgitation in dogs. DESIGN: Uncontrolled prospective study. ANIMALS: 18 dogs with naturally occurring mitral regurgitation. PROCEDURE: All dogs weighed > 5 kg (11 lb) and had severe mitral regurgitation, congestive heart failure (CHF), and no serious noncardiac disease. Left ventricular volume indices, left atrial size, and degree of mitral regurgitation were determined echocardiographically before and after surgery. Repair techniques included circumferential annuloplasty, placement of artificial chordae, chordal fenestration and papillary muscle splitting, and edge-to-edge repair. Factors predictive for surgery survival and resolution of CHF were determined. RESULTS: 12 dogs survived surgery. Factors predictive for surgery survival included weight > 10 kg (22 lb) and CHF of less than 6 months' duration. In 9 dogs, CHF resolved for a median period of 1 year (range, 4 months to 3 years) after surgery. One dog had stable CHF at 12 months. One dog died as a result of progressive CHF; another was euthanatized for a noncardiac reason. Left ventricular diastolic volume index was 226.9 +/- 117.7 cm3/m2 before surgery and 134.9 +/- 70.4 cm3/m2 at 6 months after surgery (n = 10). Factors predictive for resolution of CHF included left ventricular diastolic volume index < 250 cm3/m2 and systolic volume index < 70 cm3/m2. CONCLUSION AND CLINICAL RELEVANCE: Mitral valve repair may resolve CHF in dogs with severe mitral regurgitation, particularly in dogs that weigh > 10 kg and are treated within 6 months of the onset of CHF.     

Closed Transventricular Dilation of Discrete Subvalvular Aortic Stenosis in Dogs

Discrete subvalvular aortic stenosis with peak systolic pressure gradients of more than 60 mm Hg was treated by closed transventricular dilation in six young dogs. Peak systolic pressure gradients were measured by direct catheterization before surgery, immediately after dilation, and 3 months after surgery. Maximum instantaneous pressure gradients were measured by continuous wave Doppler echocardiography before surgery and 6 weeks to 9 months after surgery. All dogs survived the procedure, and two dogs were clinically normal after 9 and 14 months. Two dogs died at week 6 and month 7. One dog was receiving medication for pulmonary edema 15 months after surgery. One dog underwent open resection of the subvalvular ring at month 3, and was clinically normal 6 months after the second procedure. Complications included intraoperative ventricular fibrillation in one dog, and mild postoperative aortic insufficiency in one dog. Closed transventricular dilation resulted in an immediate 83% decrease in the peak systolic pressure gradient from a preoperative mean of 97 +/- 22 mm Hg to a mean of 14 +/- 15 mm Hg. However, systolic pressure gradients measured by direct catheterization at month 3 (77 +/- 26 mm Hg), and by Doppler echocardiography at week 6 to month 9 (85 +/- 32 mm Hg) were not significantly different from preoperative values, which suggested recurrence of the aortic stenosis. Closed transventricular dilation should not be considered a definitive treatment for discrete subvalvular aortic stenosis in dogs, but may be useful in young dogs with critical aortic stenosis as a bridge to more definitive surgery.     

Outcomes and complications associated with ventral screws, pins, and polymethyl methacrylate for atlantoaxial instability in 12 dogs

Clinical outcomes and complications of a technique used for atlantoaxial stabilization were evaluated in a group of 12 dogs. At surgery, the atlantoaxial joint was realigned and rigidly fixated using cortical bone screws, K-wire, and polymethyl methacrylate. Results in nine dogs were graded as excellent. Results in two dogs were judged as good. One dog was euthanized 17 months after surgery for recurrent cervical pain. Eight dogs had no postoperative complications. The surgical technique described provided an adaptable method for the correction of atlantoaxial instability.     

犬腰椎间盘切除术入路探索

为了探索治疗犬腰椎间盘突出症的合理手术入路,选择2月龄～1岁龄临床健康的本地杂交犬5只,分别编为1号～5号犬,其中1号、2号、3号犬施行半侧椎板切除术,4号、5号犬施行全椎板切除术,手术2周后进行X线摄片并剖检其腰椎结构变化。结果显示,术后1号～3号犬精神状态良好,饮食欲及体温正常,术部切口正常愈合,椎间盘部分或全部髓核被顺利取出;4号、5号犬手术中大出血,经治疗4号犬痊愈,而5号犬因衰弱而死亡。结果表明,腰椎间盘切除术要求严格的无菌操作和有效控制的麻醉,术犬侧卧位保定行半侧椎板切除是良好的手术入路,能够充分显露椎间盘、打开纤维环通道和切除髓核,有利于提高手术的安全性和保持腰椎的完整性与稳定性。     

Vaginourethroplasty for Treatment of Urethral Obstruction in the Bitch

Vaginourethroplasty was performed in six bitches with infiltrative, obstructive urethral disease. The initial clinical signs included dysuria, hematuria, pollakiuria, and stranguria. Diagnosis was based on the clinical signs, plain radiography and contrast vagino-urethrogram examination, and urethral biopsy. Five dogs were diagnosed as having urethral neoplasia; the sixth dog had granulomatous urethritis. In all six dogs, up to 50% of the urethra and the urethral tubercle were resected to ensure adequate surgical margins. One dog was euthanatized 4 months after surgery for recurrence of a transitional cell carcinoma at the surgical site. Long-term resolution of the problem (minimum of 12 months) was achieved in the other five dogs. The frequency of serious complications, including urinary incontinence and ascending lower urinary tract infections, was low.     

DISCOGRAPHY AND EPIDUROGRAPHY FOR EVALUATION OF THE LUMBOSACRAL JUNCTION IN DOGS WITH CAUDA EQUINA SYNDROME

Cauda equina syndrome in the dog is a common neurologic disorder caused by compression of the spinal cord, nerve roots and spinal nerves caudal to the fifth lumbar vertebra. This paper describes the clinical signs, radiographic findings of discography and/or epidurography, and comparison with surgery or necropsy of 21 dogs with cauda equina syndrome. Discograms were performed by using a 20- or 22-gauge spinal needle introduced in a sagittal plane into the lumbosacral (LS) disc space under fluoroscopic guidance. Epidurograms were performed following discography by injecting contrast medium after repositioning the tip of the needle into the ventral epidural space at the level of the LS junction. Direct examination of the LS junction was performed in all dogs by surgical exploration and/or necropsy. On survey radiographs, the most common findings were spondylosis, malalignment of the sacrum to the last lumbar vertebra, collapse of the LS disc space, stenosis of the vertebral canal at the LS junction, and transitional vertebral segments. Discography was considered of diagnostic quality in 19/21 (90%) of the dogs, showing disc protrusion in 14/21 (67%). Epidurography was of diagnostic quality in 18/18 (100%) dogs, showing abnormal findings in 14/18 (78%). No adverse reaction was noted to the radiographic procedure when dogs were allowed to recover from anesthesia before surgery. Based on macroscopic findings, combination of survey radiographs and disco-epidurography was correctly positive in 16/18 dogs (89%). It is concluded that discography associated with epidurography is a valuable procedure for evaluation of the LS junction in the dog. A combination of both procedures reduces the possibility of technical artifacts by outlining both sides of the compressive lesion, i.e., the disc and the epidural space.     

Granular cell tumor of the canine central nervous system: two cases.

Although pure granular cell tumors have been reported in various sites in the dog, only one tumor has been reported in the central nervous system. Two dogs presented with neurologic signs had brain lesions detected by magnetic resonance imaging in the area of the olfactory bulbs and frontal cortex. In both dogs, a clinical diagnosis of a granular cell tumor was made from tissues obtained from stereotactic biopsies guided by computed tomography. Surgical removal of the tumors was followed by histopathologic, ultrastructural, and immunocytochemical characterization. Although not conclusive, these studies indicated that the granular cells were not of leucocyte origin but may have been derived from the meninges. One dog died 12 months after surgery, and the other was alive 4 months later.     

Ureterocolonlc Anastomosis in Ten Dogs with Transitional Cell Carcinoma

Ureterocolonic anastomosis (UCA) was performed in 10 dogs with transitional cell carcinoma of the urinary bladder trigone or the urethra, or both. All grossly visible tumor was excised. All of the dogs recovered from anesthesia and surgery and had anal continence with no urine leakage. One dog died of undetermined causes 7 days after surgery. Nine dogs survived 1 to 5 months. The owners of eight of the dogs considered their dog's quality of life to be acceptable. Four dogs were euthanatized because of neurologic disease, three of which also had nausea and vomiting. The neurologic and gastrointestinal signs may have been caused by hyperammonemia, metabolic acidosis, and uremia. Blood ammonia levels were elevated in two dogs with neurologic signs. Hyperchloremic metabolic acidosis that was reversible with bicarbonate therapy was diagnosed in five dogs. All of the dogs were azotemic because of intestinal recycling of urea. Serum creatinine concentrations increased in four dogs after surgery. Drug-induced renal disease may have developed in two dogs. Pyelonephritis developed in five kidneys, two of which had outflow obstruction and two had bilateral hydroureteronephrosis before the UCA. In this small number of dogs, surgical excision of transitional cell carcinoma was not curative with six dogs having confirmed metastatic lesions at the time of death.     

Vertebral plasma cell tumors in 8 dogs

The case histories of 8 dogs with spinal pain and neurologic deficits associated with vertebral plasma cell tumor are reviewed. Four dogs had solitary plasmacytoma, 3 had multiple myeloma, and 1 dog had 2 vertebral lesions with no evidence of disseminated disease. Four dogs were treated: 2 with multiple myeloma received chemotherapy only and survived 17 and 26 months, respectively. Two dogs with solitary plasmacytomas of the spine had chemotherapy and radiotherapy: the 1st survived 4 months and was euthanized after developing radiation myelopathy; the 2nd survived 65 months before developing multiple myeloma. The diagnosis of solitary plasmacytoma of the spine versus multiple myeloma is discussed.