bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surgical Procedure Simulation via Three Dimensional Computer Aided Reconstruction of Dysplastic Canine Hips
Authors: Miller C. W. , Dobson H. , Binnington A. G. , Riley S. M. 
Published: March 2018

SummaryThe purpose of this study was to evaluate the use of three dimensional imaging techniques in veterinary orthopaedic surgery to measure hip congruity and predict changes in congruity resulting from triple pelvic osteotomies of canine hips. Preoperative, postoperative, and post-simulation measurements of congruity were obtained from eight canine hips by determination of Norberg angles from ventrodorsal pelvic radiographs (1), and lateral centre-edge (CE) angles from three dimensional (3 D) reconstructions of computed tomography (CT) scan data (2). Half of the hips were treated with a triple pelvic osteotomy with 30 degrees of axial rotation, and the other half served as approached but unoperated controls. Each measurement was performed three times by a single evaluator blinded to the identity of each hip. Lateral centre-edge angle measurements were more precise than Norberg angle measurements as determined by the calculated measurement of reliability (R = 0.78 and 0.68 respectively). Triple pelvic osteotomy resulted in an increase in congruity (as measured by lateral CE angles) of 52.2 ± 4.6 degrees compared to -3.0 ± 6.3 degrees in the control hips. The medical imaging programme used to perform the 3D reconstructions from CT scan data also allowed manipulation of the resulting preoperative 3D images to simulate on the computer screen the triple pelvic osteotomies performed on the gross specimens. Surgical procedure simulation predicted the change in congruity (as measured by lateral CE angles) of operated hips to be 43.5 ± 8.8 degrees. The images obtained by 3D reconstruction were very sensitive indicators of gross hip morphology. Visualization of structures, superimposed or surrounded by bone, was easily performed on the computer by interactive manipulation of the three dimensional CT scan reconstructions. In addition to its unique imaging capabilities, this technique appears to be a useful method for non-invasive measurement and prediction of the effects of triple pelvic osteotomy on hip congruity in dogs.Three dimensional (3D) computer aided image reconstructions were performed on tomographic scan data collected from dysplastic canine pelves before and after triple pelvic osteotomy (TPO). Descriptions of imaging capabilities and the application of lateral centre-edge angles for the determination of hip congruity are reported. Simulations performed on the computer accurately predicted the changes in congruity achieved by surgery.
Technique and Results for Total Hip Replacement in Sheep: An Experimental Model
Authors: Olmstead M. L. , Litsky A. S. , Bruns D. P. 
Published: March 2018

SummaryFifty healthy adult Suffolk cross sheep were evaluated as a research animal for cemented total hip replacement. The surgical technique, peri-operative care, and long-term evaluation of the animals is reported. A modular cemented canine hip replacement system was used in this project. Postoperative fractures of the operated femur were observed in five animals. Two sheep developed septic loosening of the acetabular components. Two sheep experienced immediate postoperative luxations. One animal developed an acetabular fracture and infection. Five sheep exhibited mild lameness of the operated limb one year postoperatively, while all others had a normal gait. Postoperative activity level played a significant role in the development of femur fractures.Fifty adult Suffolk cross sheep were evaluated as a research animal for cemented total hip replacement. The surgical technique, peri-operative care and long-term evaluation of the animals are reported.
Microangiographic Pattern of Bone Healing in Canine Tibial Osteotomies Treated with Type II External Fixators
Authors: García F. , Fuente J. , Peña T. , Prandi D. , Camón J. , Román F. , Manzanares M. C. , Franch J. 
Published: March 2018

SummaryThe morphological aspects of the vascular response, which develops in the fracture-healing process of osteotomies treated with external fixators, were evaluated by means of microangiography. Bilateral transverse midshaft osteotomies were performed in the tibiae of 16 dogs. The osteotomies were reduced by means of a Type II external skeletal fixator, and the clinical and radiographic courses were assessed weekly until the moment of euthanasia. Four dogs each were euthanatized at one, two, four and eight weeks postoperatively. After heparinization and euthanasia both femoral arteries were perfused with micronized barium sulphate, and microangiograms were performed in decalcified mid-tibial sagittal slices. Initial intramedullary revascularization as well as gap supply were already observed in some one-week microangiograms, and they were well developed in all of the two-week microangiograms. A network of parallel extraosseous blood vessels, orientated perpendicularly to the cortical surface, first appeared in the two-week microangiograms. Four weeks after the osteotomy, the extraosseous network showed its greatest degree of development whereas in the eight-week microangiograms most of the osteotomies showed only some traces of the abovementioned vascular reaction. It can be concluded that the microangiographic pattern developed in external fixated osteotomies shows many similarities with those described in experimental fractures, reduced by other means, with the earlier development of all of the vascular phenomena being the most important difference.Microangiography was used to determine the morphological characteristics of the vascular response developed in the tibial experimental fractures healing process.
An Animal Model for Research on Wound Healing over Exposed Bone
Authors: Swaim S. F. , Stuart S.W. , Bradley D. M. 
Published: March 2018

SummaryMany wounds such as degloving injuries, or dermal ulcerative processes may have exposed bone. This presents a problem in wound healing. Various procedures such as tissue flaps, skin expansion, skin grafts, or open wound healing may be used to treat wounds with exposed bone. The development of a healthy granulation tissue bed provides the supportive structural matrix and vasculature needed to promote wound healing over exposed bone. This is beneficial when flaps or expanded skin are used and is necessary if skin grafts or open wound healing are used for treatment. This paper describes an animal model and surgical technique that can be used in studying factors that might enhance wound healing over exposed bone. A technique is described whereby a rectangular defect with exposed bone is made over the second metatarsal bone of New Zealand white rabbits. Using subjective observations and objective planimetry, the rate of healing can be evaluated. The animal model and technique provide a means of evaluating effects of medications and bandages on the healing of wounds with exposed bone. The model could also be considered a model for wounds with delayed healing.This paper describes an animal model and surgical technique that can be used to study wound healing over exposed bone. The surgical technique involves the creation of a rectangular defect over the second metatarsal bone of New Zealand White rabbits, with removal of the overlying periosteum. Various topical medications and/or bandage materials can be evaluated as to their effects on the healing of wounds with exposed bone. Bilateral defects can be created, with the animal serving as its own control. Subjective and objective evaluations involving planimetry, histopathologic, biochemical, or immunohistochemical analyses of harvested tissues may be conducted.
The Expression of IL-1, IL-6, and TGF-β in the Synovial Fluid of Horses with Surgically-Induced Transient Synovitis
Authors: Barber S. M. , Gordon J. R. , Theoret Christine 
Published: March 2018

SummaryThis study investigates the presence of various cytokines in the synovial fluid of three horses with surgicallyinduced synovitis in one antebrachiocarpal joint. Synovial fluids were sampled from experimental and control joints, preoperatively and at two and 30 days post-operatively. Samples were analyzed for interleukin-1 and interleukin- 6 bioactivities with a bioassay, and for transforming growth factor-beta protein by ELISA. Peak cytokine levels were detected on day two post-synovectomy, and returned to pre-operative levels by 30 days post-synovectomy (Interleukin-6 in treated joints: day #0; 0.53 ±0.2, day #2; 9.8 ± 0.7, day #30; 0.4 ± 0.2. Transforming growth factorbeta in treated joints: day #0; 314 ± 69, day #2; 1101 ± 325, day #30; 321 ± 101). Arthrocentesis alone (i.e. control joints) caused no increase in interleukin- 1, interleukin-6 and transforming growth factor-beta levels. Interleukin-1 and interleukin-6 are thought to both prevent anabolic and enhance catabolic effects within articular cartilage matrices, whereas it has been proposed that transforming growth factor-beta may have a protective effect on the articular cartilage. This study is the first to document elevated transforming growth factor-beta levels in equine joints.This study documents elevated levels of transforming growth factor-beta, interleukin-1 and interleukin-6 in the joints of horses with surgically-induced transient synovitis.
Comparison of Cemented and Non-cemented Allografts in Dogs with Osteosarcoma
Authors: Steinheimer D. , Park R. D. , Powers B. E. , Straw R. C. , Endenburg N. , Withrow S. J. , Kirpensteijn J. 
Published: March 2018

SummaryThis study compares the radiographic and histological appearance of cemented and non-cemented massive cortical allografts in dogs that underwent a limb sparing procedure for osteosarcoma of the distal radius. Treatment consisted of removal of the affected bone and pancarpal arthrodesis using non-cemented (n = 13) or cemented (n = 47) fresh-frozen allografts. Allografts were evaluated using a radiographic and histological scoring system and compared statistically between groups. Allografts with better healing received a higher radiographic score and a lower histological score. The mean radiographic scores, for proximal union and distal union, were significantly greater in the non-cemented group at most evaluation periods. Complications after the operation included screw, plate, allograft and host bone failure, infection and local tumour recurrence. Screw failure in the allograft and allograft failure were significantly more common in the non-cemented group. Histological examination was performed on 44 dogs and cement increased the mean combined histological scores, and mean healing scores of the distal host-graft interface significantly. The use of cemented allografts significantly decreases complications associated with implant loosening or allograft failure but may slightly delay allograft healing. At this point, the clinical relevance of the delay in healing is questionable and the benefits of intramedullary PMMA would appear to outweigh this relative delay in healing.This study evaluated 60 radial allografts after limb sparing procedures using a standardized radiological and histological scoring system. The use of cemented allografts significantly decreased complications associated with implant loosening or allograft failure but may slightly delay allograft healing.
Bilateral Pes valgus Deformity in a Shetland Sheepdog
Authors: McCarthy P. E. 
Published: March 2018

SummaryAn eight-month-old, 19.7 kg, male Shetland Sheepdog was diagnosed with a valgus deformity present in both hindlimbs. Anamnesis failed to reveal a traumatic incident to explain the deformities. Bilateral tibial osteotomies and placement of an external skeletal fixation were used in the correction of the defects. Several reports exist concerning angular limb deformities of the rear limb in Shetland Sheepdogs. These facts may represent a breed at risk for such defects.An eight-month-old Shetland Sheepdog with bilateral valgus deformities of the tibiotarsal joint was managed by staged bilateral corrective tibial osteotomies and placement of an external skeletal fixation. Reports of angular limb deformities of Shetland Sheepdogs are reviewed.
Detection of Stress-Generated Potentials in Fracture Callus
Authors: Marsico P. J. , Roe S. C. 
Published: March 2018

SummaryStress generated potentials (SGPs) are present in cortical bone and are thought to contribute to osteocyte perception of load. Because callus also develops and remodels in response to mechanical stimulus, SGPs may be the signaling mechanism in this tissue. The feasibility of the measurement of SGPs in fracture callus was investigated in this study. Osteotomies were performed on the right ulna of 15 Mongrel dogs and allowed to heal without fixation. The ulnae were harvested at six, 12, and 18 weeks; each callus instrumented with electrodes and SGPs recorded during broad band dynamic vibrational excitation. The results of these measurements indicate that SGPs can be detected in fracture callus. Refinement of the measurement techniques may lead to a better understanding of these potentials and how they change with load magnitude and stage of healing. Understanding of SGPs in vivo may also contribute to development of electromagnetic fracture healing stimulation methodologies.Stress generated potentials (SGPs) are a probable mechanism through which cells in cortical bone sense and respond to load. In this study, SGPs were identified in fracture callus, a tissue that also responds to load by remodeling. Further study of these potentials may assist in the development of methods for stimulation of fracture healing.This material was presented at the American College of Veterinary Surgeous Magazine Meeting, Washington, DC, October, 1994.
Force Plate Analysis of Dogs with Bilateral Hip Dysplasia Treated with a Unilateral Triple Pelvic Osteotomy: A Long-term Review of Cases
Authors: Cockshutt Joanne R. , Dobson H. , Miller C. W. , Holmberg D. L. , Taves Connie L. , Tano Cheryl A. 
Published: March 2018

SummaryA retrospective case series study was done to determine the long-term outcome of operations upon dogs treated for canine hip dysplasia by means of a triple pelvic osteotomy (TPO). Twentyfour dogs with bilateral hip dysplasia, that received a unilateral TPO between January 1988 and June 1995, were re-examined at the Ontario Veterinary College. The assessment included physical, orthopedic and lameness examinations, standard blood work, pelvic radiographs and force plate gait analysis. They were compared to bilaterally dysplastic dogs that had not been treated, and also to normal dogs. Force plate data analysis demonstrated a significant increase in peak vertical force (PVF) and mean vertical force over stance (MVF) in the limb that underwent surgical correction by means of a TPO, when compared to the unoperated hip. It was determined that performing a unilateral TPO on a young dysplastic dog resulted in greater forces and weight bearing being projected through the TPO corrected limb when compared to the unoperated limb.Dogs with bilateral hip dysplasia treated with a unilateral triple pelvic osteotomy (TPO) were assessed by force plate gait analysis, radiographs and orthopedic examination. There was a significant increase in hip Norberg angles over time, although degenerative changes did progress. Limbs that had been operated upon had significantly greater peak and mean ground reaction forces than limbs that had not received an operation.
Clinical Response to Antibiotic Impregnated Polymethyl Methacrylate Bead Implantation of Dogs with Severe Infections after Limb Sparing and Allograft Replacement -18 Cases (1994-1996)
Authors: Withrow S. J. , Straw R. C. , Powers B. E. , Wember E. W. , Jameson V. J. , Wilkins R. M. , Allen R. E. , Dernell W. S. 
Published: March 2018

SummarySuccessful treatment of severe orthopaedic infections in people and animals has been augmented by the use of antibiotic impregnated polymethyl methacrylate (PMMA) bead implantation at the site of infection. High local wound concentrations of antimicrobials can be achieved without resulting in toxic levels systemically. Clinical, radiographic and pathological response was evaluated following PMMA beads impregnated with vancomycin and tobramycin implanted in 18 dogs with severe infections following “limb sparing” operation with allograft replacement for osteosarcoma. A variety of aerobic and anaerobic bacterial organisms were cultured from the sites of infection and numerous systemic antimicrobial drug combinations were used in an attempt to control the infections prior to the implantation of the beads. In 12 of 18 (67%) dogs implanted, clinical signs of infection resolved within a median of four weeks post implantation. Three of 12 (25%) had recurrence of signs at a median of 17 weeks post implantation. This was not a randomized, prospective controlled trial and limitations to the study exist, the most notable being the variability in individual patient treatment. However, antibiotic impregnated PMMA bead implantation may play a role in the treatment of severe infections in dogs.Eighteen dogs with severe infections were implanted with polymethyl methacrylate beads impregnated with tobramycin and vancomycin. In 67% of dogs implanted, clinical signs of infection resolved within a median of four weeks. Antibiotic impregnated PMMA bead implantation may play a role in the treatment of severe orthopedic infections in dogs.This study was supported in part by grant number 2 PO1 CA 29582 from the National Cancer Institute. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute, USA.
Backscattered Electron Imaging of the Calcified Tissues Present in Bone Healing
Authors: García F. , Camón J. , Manzanares M. C. , Franch J. 
Published: March 2018

SummaryThe aspect of calcified tissues involved in fracture healing was studied by means of backscattered electron imaging. Bilateral transverse midshaft osteotomies were performed in the tibiae of 16 dogs. The osteotomies were reduced by means of a type II external skeletal fixator, and the clinical and radiographic course was assessed weekly until the moment of euthanasia, one, two, four and eight weeks after the operations. The osteotomized areas were removed and their structure examined in the scanning electron microscope, using backscattered electron images, to determine the general aspect of the extracellular matrix of the calcified tissues present. Four different tissues were observed: lamellar bone, woven bone, calcified cartilage and chondroid tissue. The backscattered electron contrast and fibre arrangement of the matrix, as well as the size and shape of the cellular lacunae, allow identification of the tissue. Chondroid tissue, which seems to have a leading role in the early phases of fracture healing, shows a characteristic pattern of a highly calcified and fibrous matrix with a large number of irregular and confluent cell lacunae.The morphological characteristics of the calcified tissues involved in fracture healing were studied by means of backscattered electron imaging. Lamellar bone, woven bone, calcified cartilage and chondroid tissue were the four calcified tissues observed during the healing process of canine midshaft tibial experimental fractures.
Looming changes in the management of “osteoporosis”: A preview for clinicians
Authors: Frost H. M. 
Published: March 2018

SummaryNormally, strong muscles make strong load-bearing bones, and persistently weak muscles make weak ones. We now have a general understanding of how and why that happens. Unexpectedly that understanding also affects our understanding of the nature, pathogenesis and study of disorders currently classified as “osteopaenias” and “osteoporoses”. Such things promise to change how we view, study and manage those disorders. At present, those things incite discussions among authorities that in time should lead to a new accepted “wisdom” about those disorders. Many clinicians who manage patients on a daily basis would probably like to know what issues that process concerns. Because of the importance of those issues to so many millions of this planet's present and future six billion souls, and because of their bearing on the related research, one could argue that clinicians and researchers are entitled to know about those issues. For that reason this article summarizes some of them, of course as I seem them.It is understood that other times, places and people would resolve any questions about those issues, and that any new accepted wisdom that depends upon their resolution should lie in the future.Recent recognition of the effects of muscle and biomechanics on the biologic ‘‘machinery” that determines whole-bone strength and bone health incite many changes in formerly accepted views about the nature, diagnosis, pathogenesis, study and management of the group of different disorders that are currently considered as falling under the umbrellas of “osteoporosis” and “osteopaenia”. This article acquaints interested physicians with some of those changes and the reasons for them. It should take time, probably several years, for those changes to gel into an accepted new standard of care for such disorders. Meanwhile currently accepted standards of care could and probably should be followed.
Palpation and dorsal acetabular rim radiographic view for early detection of canine hip dysplasia
Authors: Dupuis J. , Beauregard G. , Breton L. , Paré J. , Charette B. 
Published: March 2018

SummaryThe objectives of this study were to standardize a palpation technique and to determine within and between examiners, the repeatability in interpreting the angle of reduction, subluxation and the acetabular slope measurements. Also it was desired to ascertain the effect of pelvis positioning on the acetabular slope measurement on sixmonth- old dogs. On palpation examination fifty-three (53) dogs had their angles of reduction and subluxation measured. A radiographic examination including a standard hip-extended view, a compression and a distraction view and a dorsal acetabular rim view were performed on each dog.The within examiner repeatability was excellent for both the angle of reduction and subluxation (r = 0.975, p = 0.82 and r = 0.977, p = 0.81 respectively). The between examiners repeatability was good for the angle of reduction (r = 0.843, p = 0.51) but only a fair correlation was found for the angle of subluxation (r = 0.652, p = 0.83). For the acetabular slope measurement, an excellent within examiner correlation was observed (r = 0.940, p = 0.52). However, though a good correlation was found between examiners, a significant difference was found in the measurements of the three examiners (r = 0.780, p < 0.0001). The under- or overrotation position slightly changed the slope measurement but a fair correlation was still observed with the perfect position (r = 0.769, p = 0.074 and r = 0.684, p = 0.061 respectively). If the pelvis is turned to one side, a correlation was not found (r = 0.090, p = 0.847). The high repeatability of the angle of reduction measurement in six-month-old dogs suggests that it may be used by multiple examiners, with the expectation of comparable and consistent results. The modified method of the acetabular slope measurement improved the correlation, but a significant difference was still observed between examiners.Early detection in life of canine hip dysplasia is important. The angle of reduction and the acetabular slope have been evaluated as diagnostic tools. With regard to its repeatability between examiners, the use of the angle of reduction by multiple examiners will be acceptable. The correlation between examiners in the acetabular slope measurement was good but a significant difference was present. Part two is now being analyzed.