摘要:

The biomechanical characteristics of a 4‐ring circular multiplanar fixator applied to equine third metacarpal bones with a 5 mm mid‐diaphyseal osteotomy gap were studied. Smooth Steinmann pins, either 1/8 inch, 3/16 inch, or 1/4 inch, were driven through pilot holes in the bone in a crossed configuration and full pin fashion and fastened to the fixator rings using cannulated fixation bolts. The third metacarpal bone fixator constructs were tested in three different modes (cranial‐caudal four‐point bending, axial compression, and torsion). Loads of 2,000 N were applied in bending and axial compression tests and a load of 50 N ± m was applied during testing in torsion. Fixator stiffness was determined by the slope of the load displacement curves. Three constructs for each pin size were tested in each mode. Comparisons between axial stiffness, bending stiffness, and torsional stiffness for each of the three different pin sizes were made using one‐way analysis of variance. There was no visually apparent deformation or permanent damage to the fixator frame, and no third metacarpal bone failure in any of the tests. Plastic deformation occurred in the 1/8 inch pins during bending, compression, and torsion testing. The 3/16 inch and 1/4 inch pins elastically deformed in all testing modes. Mean (±SE) axial compressive stiffness for the 1/8 inch, 3/16 inch, and 1/4 inch pin fixator constructs was: 182 ± 16 N/mm, 397 ± 21 N/mm, and 566 ± 8.7 N/mm; bending stiffness was 106 ± 3.3 N/mm, 410 ± 21 N/mm, and 548 ± 12 N/mm; and torsional stiffness was 6.15 ± 0.82 N.m/degree, 7.14 ± 0.0 N±m/degree, and 11.9 ± 1.0 N.m/degree respectively. For statically applied loads our results would indicate that a 4‐ring fixator using two 1/4 inch pins per ring may not be stiff enough for repair of an unstable third metacarpal bone fra

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01370.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

The association of myelographic spinal cord swelling with neurological outcome was examined in 46 dogs with intervertebral disc disease and absence of deep pain perception (DPP). Spinal cord swelling was measured by calculating a ratio of the length of the loss of the myelographic dye column to the length of the second lumbar vertebra (L2). A positive neurological outcome was defined as return of voluntary motor function. A cut‐off value for swelling:L2 of 5.0 was established by the creation of a receiver operator characteristic curve. Using a swelling:L2 ratio of 5.0 as a cutoff for indication of neurological recovery yielded a sensitivity of 74% and a specificity of 61%. Overall neurological recovery rate was 43%. Dogs with spinal cord swelling: L2 ratios less than 5.0 had a recovery rate of 61%, whereas dogs with a ratio greater than or equal to 5.0 had a recovery rate of 26%. Evaluation of these data by chi square analysis confirmed that a ratio less than 5.0 was associated with a positive outcome, and a ratio greater than or equal to 5.0 was associated with a negative outcome, (P<.05). Although other factors, such as duration of neurological signs, affect neurological outcome in dogs with no DPP, evaluation of myelographic spinal cord swelling can assist in establishing a prognosi

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01371.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Renal transplantation is a successful treatment for terminal renal failure in cats. However, in the initial clinical study, there was a frequent occurrence of obstruction of the implanted ureter at the bladder wall or stoma. This resulted in the use of a modified “drop‐in” technique that had proved effective in the prevention of obstruction in five normal cats. When applied to renal transplant recipients, ureteral obstruction was reduced, but continued to occur. The modified “drop‐in” technique was abandoned and replaced with a technique that apposed the cut edge of the ureteral mucosa to the torn edge of the bladder mucosa. This technique is recommended as it has prevented ureteral obstruction in six successive cases. Prevention of ureteral obstruction, and the required corrective surgery, markedly reduces patient morbidity and mortality, length of hospitalization, and expense to

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01372.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Deep‐frozen, aseptically collected and processed allogeneic cancellous bone was implanted in eight dogs during the surgical repair of diaphyseal long bone fractures and in two dogs during arthrodeses. A combined allogeneic and autogeneic cancellous bone graft was used in two fractures with a segmental bone loss of more than 5 cm. Bone union occurred in five fractures and in both arthrodeses. Failure of fixation occurred in two dogs with nonunion fractures and in a third dog with an open, infected fracture. Biopsies from the fracture sites were obtained from these dogs following failure of their fracture fixation. The cancellous bone graft appeared to be in the process of normal incorporation in each case. Failure of fixation was attributed to technical or case management errors or both, in each of the three fractures that failed to achieve bony union. Frozen allogeneic cancellous bone grafts were effectively incorporated when used in the primary repair of fractures and arthrodeses. Combined autogenous and allogeneic cancellous bone grafts may be particularly useful in the repair of fractures with large segmental diaphyseal bone defects. The use of allogeneic cancellous bone grafts in nonunion fractures requires further investigation before it can be recommende

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01373.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Controlled cross circulation (CCC) was performed in six pairs of dogs for 45 minutes with aortic cross clamping and cardioplegia. Data were collected in donor dogs at 10 minute intervals three times before, three times during, and three times after CCC and included arterial blood pressure, pulmonary capillary wedge pressure (PCWP), central venous pressure (CVP), cardiac index (CI), heart rate (HR), blood gas analysis, temperature, maximum rate of rise of left ventricular pressure dP/dt max/End diastolic volume (EDV), blood volume (BV), complete blood count (CBC) and activated clotting times (ACT). Pulse pressure (PP), systemic vascular resistance (SVR), oxygen delivery (Do2), and left ventricular cardiac work (LVCW) were calculated. Arterial blood pressure, CVP, blood gas analysis, temperature, BV, CBC, and ACT were measured in recipient dogs. During CCC, donor hemodynamic changes resembled those observed in models of acute onset arteriovenous fistulas. Insidious BV shifts can occur despite the use of occlusive roller pumps. After CCC, donor hemodynamics resembled acute blood loss, characterized by decreases in mean arterial pressure (MAP), CVP, PCWP, and CI, and increases in SVR and dP/dt max/EDV. These changes were probably caused by pump imbalance and BV shift to the recipient dog.

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01374.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Anatomic and experimental evaluation of the feline latissimus dorsi muscle was performed to assess its potential use as a free muscle flap. In the anatomic study, nonselective angiography of the subscapular artery was performed in nine heparinized feline cadavers. The muscle dimensions and vascular anatomy of the dissected latissimus dorsi muscle were recorded. In the experimental study four cats underwent heterotopic transplantation of a partial latissimus dorsi flap, and three cats underwent orthotopic transplantation of a complete latissimus dorsi flap. The mean length and width of the latissimus dorsi muscle was 19.0 and 5.4 cm, respectively. The dominant vascular pedicle was the thoracodorsal artery and vein. The average length and diameter of the thoracodorsal artery was 2.7 cm and 0.6 mm, respectively. Minor vascular pedicles were provided by branches of the intercostal arteries. Numerous choke anastomoses existed between the two pedicle systems. Viability of muscle flaps based on subjective evaluation, angiography, and histopathology, was 66% and 100% in the heterotopic and orthotopic studies, respectively. Flap failure seemed to be caused by both arterial and venous thrombosis. The latissimus dorsi muscle flap met criteria required for application in microvascular reconstruction. The vascular pattern was appropriate and consistent. Donor site morbidity was low, whereas surgical accessibility was high. The muscle satisfied the physical criteria of a free flap. Long‐term anastomotic patency and flap viability was show

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01375.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

The need for alternative methods of teaching veterinary medicine and surgery has increased in recent years because of increasing costs and changing public opinion. For these reasons a hemostasis model was developed that mimics the arteries and veins of the peripheral vascular system, and can be used to teach the basic skills involved in blood vessel ligation and division. This study evaluated the effectiveness of the fluid hemostasis model compared with using live animals for teaching these skills. Forty sophomore veterinary students participated in the study. Two groups of 20 students each received identical instruction in the basic techniques required for vessel ligation and division. The students then completed various exercises using inanimate models to objectively evaluate their psychomotor skills. Both groups then practiced the techniques for equal time periods; one group used the hemostasis model and the other performed a splenectomy on live dogs. After the practice session, the students were videotaped (for later evaluation), as they performed vessel ligations and divisions. The students then repeated the exercises using the inanimate models for evaluation of skills improvement. Questionnaire responses before and after the project were obtained to determine the students' views on the need for inanimate models for teaching purposes. Results of this study indicate that the hemostasis model was as effective as live animals for teaching the basic skills involved in blood vessel ligation. The students' opinions regarding the use of properly designed inanimate models for teaching these skills were dramatically changed.

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01376.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

A prospective study was undertaken to compare the analgesic effect of intra‐articular bupivacaine, morphine, or saline in the 24‐hour period following cranial cruciate ligament repair in dogs. Thirty‐six clinical patients with ruptured cranial cruciate ligaments were randomly assigned to one of three groups. After surgical stabilization, and before skin closure, an intra‐articular injection was given; group one (n = 12) received 0.5% bupivacaine HCl at 0.5 mL/kg, group two (n = 12) received morphine at 0.1 mg/kg diluted with saline to a volume of 0.5 mL/kg, and group three (n = 12) received saline at 0.5 mL/kg. Heart rate, respiratory rate, mean arterial blood pressure, cumulative pain score, visual analog pain score, and pain threshold test on both stifles were recorded preoperatively and at 0 to 6 and 24 hours postoperatively. Surgeons and pain scoring investigators were unaware of the intra‐articular medication given. Supplemental analgesia, if needed, was provided in the postoperative period according to subjective assessment of patient discomfort. Postoperative pain scores were lowest in the bupivacaine group and highest in the saline group. Pain threshold, measured by applying calibrated loads to the knee, was higher postoperatively in the bupivacaine group than in the saline group. Dogs in the morphine and bupivacaine groups required less supplemental analgesia than dogs in the saline group. The local provision of analgesia reduces the need for systemic drugs with potential side effects. Both intra‐articular morphine and intra‐articular bupivacaine provided better postoperative analgesia than intra‐articular saline, with intra‐articular bupivacaine showing th

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01377.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

This report presents a case of osteosarcoma of the femoral diaphysis associated with chronic stimulation of the area by an unstable femoral prosthesis after total hip arthroplasty performed 8 years previously. The pathogenesis of this transformation may be similar to that proposed for fracture‐associated sarcoma. Neoplasia should be considered as a possible late complication of total hip arthroplast

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01378.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

ISSN:0161-3499    

DOI:10.1111/j.1532-950X.1996.tb01379.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY