[Show abstract][Hide abstract] ABSTRACT: Objectives:
The aim of the study was to evaluate the prevalence, size, location and appearance of mineralisations in feline stifle joints, and to evaluate their relationship with osteoarthritis and cranial cruciate ligament (CrCL) status.
Presence or absence, and size of mineralisations were determined from lateral stifle radiographs of 25 cats with CrCL rupture, and 44 cat cadavers without CrCL rupture. Mineralisations were classified as small, medium or large. Prevalence was compared between the clinically affected cats and the cadavers; the cadaver group was subdivided into an age-matched and an older group. Ten stifles with varying sizes of mineralisations were prepared as whole-knee specimens for histopathology. Location and appearance of the mineralisations, and degenerative changes in the cruciate ligaments, menisci, articular cartilage and joint capsule are described.
Prevalence of articular mineralisations was 0.76 in stifles of cats with CrCL rupture (mean ± SD age 8.6 ± 4.5 years), 0.64 in stifles of age-matched cat cadavers and 0.74 in older cat cadavers (mean ± SD age 17.0 ± 2.4 years). Cats with CrCL rupture had a higher percentage of medium and large mineralisations than cats without CrCL rupture. Microscopically, small mineralisations were calcifications usually located in the cranial horn of the medial meniscus. Larger mineralisations were found to be ossifications, commonly located in the joint capsule and fat pad. Cats with larger mineralisations showed more signs of osteoarthritis, including degenerative changes in the CrCL.
Conclusions and relevance:
Mineralisations in feline stifle joints were found to differ in size, appearance and location. Small mineralisations were usually confined to the medial meniscus as described previously; larger mineralisations tended to be located in the tissues cranial to the menisci and seemed to be associated with osteoarthritis and CrCL pathology. Large mineralisations in feline stifles are ossifications in periarticular tissue and are associated with degenerative joint disease.
[Show abstract][Hide abstract] ABSTRACT: For some time Norwich terriers have been known to suffer from respiratory problems. In order to assign this weakness to a pathophysiology, 23 terriers were examined clinically, with laryngoscope and with rhinomanometry. In addition their skulls were dimensioned on radiographs. Widened nostrils, overlong soft palates and the everted laryngeal pouches were consistent with brachycephalic syndrome. Resistance values in the nasal passage corresponded to the appearance in brachycephalic dogs. Skull measurements gave inconsistent results, because length to width ratios and craniofacial angles denoted mesaticephaly, whereas the facial to cranial length ratios (S-index = 0.65) lay in the brachycephalic sector. It can be concluded, that the Norwich terrier breed is in transition towards brachycephaly with some individual dogs already suffering from the brachycephalic syndrome. Breeders are requested to introduce necessary counter measures.
[Show abstract][Hide abstract] ABSTRACT: To describe medial humeral epicondylitis in cats based on radiographic, anatomic, and histologic observations.
Prospective cohort study.
Feline cadavers (n = 60).
Extended craniocaudal, and extended and flexed mediolateral radiographic projections were taken of both elbows of 60 consecutive European shorthair cats that died or were euthanatized. Elbows with new bone formation at the medial epicondyle were dissected and embedded in methyl-methacrylate (MMA). For comparison, both elbows of a cat with no radiographic changes were prepared in a similar manner. Sections of the MMA blocks were Giemsa stained and examined with light microscopy.
Bilateral new bone formation was identified radiographically at the medial aspect of the humeral epicondyle in 6 cats (10%). All of these cats had mineral deposition in the humeral head of the flexor carpi ulnaris muscle. Other findings were cartilage damage (n = 3 cats), an additional loose medial joint body (1), and tendinosis (3). The ulnar nerve was flattened and displaced caudally, and signs of chronic epineural fibrosis were present in 2 severely affected cats.
Ten percent of this feline population had radiographic evidence of medial humeral epicondylitis with chronic degeneration, mineralization, and metaplastic bone formation in damaged fibrillar matrix involving the origin of the humeral head of the flexor carpi ulnaris muscle. New bone formation caused displacement and compression of the ulnar nerve in severely affected elbows. Based on our findings, medial humeral epicondylitis appears to be a common disorder in cats with potential clinical sequelae.
Full-text · Article · Aug 2012 · Veterinary Surgery
[Show abstract][Hide abstract] ABSTRACT: In veterinary medicine, limb-sparing techniques are most implemented when the uninvolved limbs are affected by other orthopaedic or neurological disorders, in large breeds or when the owner declines amputation. This report describes the surgical technique used for implantation of an endoprosthesis following tumour resection in the distal radius in 3 dogs using both standard and angle-stable plates. Endoprosthesis offers an easy and readily available surgical alternative to cortical allografts. Despite post-operative complications, this technique resulted in a good quality of life in all 3 dogs.
Preview · Article · Aug 2012 · SAT Schweizer Archiv für Tierheilkunde
[Show abstract][Hide abstract] ABSTRACT: Measurements of the canine skull are of main interest in brachycephalic dogs. They are suspected to have di-seases associated with the shortened nose, which are summarized under the term brachycephalic syndrome. The relative length of the nose has become an important feature in breeding and research, although a defi nitive correlation to the brachycephalic syndrome still has not been proven (Knecht, 1979; Harvey, 1982; Aron und Cro-we, 1985; Koch et al., 2003). Classifi cations of skull types can be made by two methods. The traditional phenoty-pic assignment into brachycephalic, mesaticephalic and dolichocephalic is based on the assumption, that dogs of a specifi c breed have more or less uniform skull sha-pes. However, alterations due to breeding and differences be tween individual dogs of the same breed must lead to modifi cations. Therefore and for a more subtle classifi -cation, skull measurements were introduced (Brehm et al., 1985; Evans, 1993; Regodon et al., 1993), The existing indexation methods from Evans (1993) and Brehm et al. (1985) are based on cadaver studies. They classify brachycephalic dogs as having a cranial length to facial length ratio (LL-index) of > 1.60 or a skull length to skull width ratio (LW-index) of < 1.44. However, the authors also mentioned the considerable range of those indices within a breed. Regodon et al. (1993) were the fi rst to propose a classifi cation based on radiographs of canine skulls with the craniofacial angle (CFA) as a cri-terion. The CFA is defi ned by a line along the base of the skull, and another line along the hard palate. The CFA of 10 dogs from 5 breeds were retrieved and it was found that the ranges clearly overlapped. The existing indices have their limitations for clinical use, either being based on cadavers (LL-index, LW-index) or not resulting in meaningful assignments of the individual skull meas-urement to the phenotypic appearance of the respective breed (CFA). We therefore propose a possible new skull index (S-index), which can be easily derived from radio-graphs of living animals and should refl ect the phenotype of each individual. Such an index has also the potential to be linked to airstream parameters (Wiestner et al., 2007) and to the clinical manifestation of respiratory problems of each individual. It offers an insight to different skull shapes between dogs of the same breed. We also propose a boundary value, which should have the potential to classify between brachycephalic and non-brachycephalic skull shapes. The new S-index is an approximation to the LL-index, retrieved form cadavers by Brehm et al. (1985). The in-dex however was taken from radiographs in dorsoventral direction (Fig. 1). It is calculated by the length of the fa-cial skull divided by the length of the cerebrum. In this context the length of the facial skull was defi ned as the distance from the rostral border of the incisal bone to the rostral border of the cavum cranii. The length of the cerebrum was measured from the rostral border of the cavum cranii to the caudal outline of the occipital bone, beginning at the dorsal border of the great foramen. The S-index was compared to the LW index and the CFA on 57 dogs of different breed, sex, age and size. They were presented to the University of Zurich for planned surgical procedures (mainly neutering). The owners agreed to the procedures necessary for this study. From all dogs, radio-graphs of the skull in dorsoventral (hard palate parallel to the table, Fig. 1) and laterolateral direction (hard palate perpendicular to the table, Fig. 2) were taken. The S-and LW-index (dorsoventral views) and CFA (laterolateral views) were determined (Tab. 1). A boundary value (BV) for the S-index was evaluated which allows for a separation of the brachycephalic and the non-brachycephalic breeds by the following method. First, the dogs in the present study were classifi ed on the basis of the established separating BV for the LW-index (Brehm et al., 1985). Secondly, the BV of S-index was determined such that the highest score in coincidence of classifi cation occurred for both, the brachycephalic and non-brachycephalic breeds . In this manner, it was found that all dogs having an S-index equal or below the BV of 1.25 are considered to have a brachycephalic skull shape (Tab. 1). In parallel the respective CFA were listed.
Full-text · Article · May 2012 · SAT Schweizer Archiv für Tierheilkunde
[Show abstract][Hide abstract] ABSTRACT: To compare biomechanical characteristics of vertebral segments after vertebral body plating or laminar stabilization following complete incision of the annulus fibrosus.
Vertebral segments from T13 through L3 obtained from 18 canine cadavers.
A 4-point bending moment was applied in flexion and extension to the intact vertebral segments to determine a baseline range of motion (ROM) and neutral zone (NZ). Vertebral columns were then destabilized by creating a defect in the intervertebral disk via complete incision of the ventral aspect of the annulus fibrosus. The bending moment was applied again after stabilization was accomplished via vertebral body plating or with laminar stabilization (n = 9 vertebral segments/stabilization technique). The ROM and NZ were compared with their baseline values and among treatment groups. Finally, load-to-failure testing was performed in flexion.
Mean relative ROM and NZ for segments treated with laminar stabilization were significantly lower than those for segments treated with vertebral plates.
Analysis of in vitro results suggested that laminar stabilization of vertebral segments provided greater stiffness than did vertebral body plating.
Full-text · Article · Dec 2011 · American Journal of Veterinary Research
[Show abstract][Hide abstract] ABSTRACT: To determine angles of insertion for laminar vertebral fixation of L1 and L2 by use of a locking plate in dogs and to confirm screw placement by use of computed tomography (CT).
Vertebral specimens harvested from 8 canine cadavers.
The point of insertion and minimum and maximum insertion angles for laminar and facet screws for laminar vertebral stabilization were determined by use of CT. A precontoured locking plate was then placed by use of 1 locking screw in the lamina of each lumbar vertebra and 1 nonlocking screw in the facet joint. The position and angle of the screws were examined by use of CT, and penetration into the vertebral canal was recorded.
Mean ± SD insertion angles for L1 and L2 were 18 ± 4° and 21 ± 5° toward the vertebral canal and 11 ± 4.4° and 10 ± 3° in a dorsal direction, respectively. Insertion angles for the facet joint were between 24 ± 4° ventrally and 12 ± 2° dorsally. Insertion of the screw did not penetrate the vertebral canal for 23 of 24 (96%) screws. For 23 of 24 inserted screws, the previously determined angle was maintained and purchase of bone and cortices was satisfactory.
Placement of laminar and facet screws in canine vertebrae was possible and can be performed safely if angles of insertion determined pre-operatively via CT are maintained.
Full-text · Article · Dec 2011 · American Journal of Veterinary Research
[Show abstract][Hide abstract] ABSTRACT: An eight-year-old, neutered female Rottweiler was presented with lameness of seven days duration. Radiographs were consistent with a distal radial bone tumour. Limb-sparing surgery was performed using a commercially available endoprosthesis with a locking bone plate. Histopathological examination of the resected bone revealed an intraosseous fibrosarcoma, and postoperative adjuvant chemotherapy was initiated three weeks after surgery. Despite initial satisfactory limb function, lameness worsened four months after surgery. Radiographs revealed large areas of bone lysis around the proximal and distal screws, leading to significant resorption of the radius and radial carpal bone with subsequent construct failure. Further treatment was declined by the owner and the dog was subsequently euthanased. This case illustrates that implant failure is not necessarily averted by the use of locking (compared with non-locking) implants combined with an endoprosthesis to treat distal radial tumours in dogs.
No preview · Article · Nov 2011 · Journal of Small Animal Practice
[Show abstract][Hide abstract] ABSTRACT: To (1) determine suction tip (intermittent and continuous mode) contamination rate in orthopedic surgery in dogs and cats; (2) examine the effect of surgical time on contamination; and (3) report bacteria isolated.
Clean orthopedic surgeries (n = 50).
Surgical procedures were assigned to 1 of 2 groups: (1) continuous (n = 25) or (2) intermittent suction (n = 25). A control suction was operated in each surgery. Samples for aerobic and anaerobic bacteriologic examination were collected from the surgical suction at 0, 20, 60 minutes, and at the end of surgery, and from the control suction at the end of the surgery only. Comparison of continuous and intermittent suction data, and the effect of surgical time on contamination rate were analyzed using a Kaplan-Meier survival analysis followed by a Cox proportional hazards model. P < .05 was considered significant.
Aerobic contamination occurred in 22 of 50 surgical procedures and there was no anaerobic growth. There was no significant difference between continuous and intermittent suction mode groups (P = .40). Surgical time did not influence the contamination rate (P = .79). Bacterial cultures mainly revealed coagulase-negative Staphylococci, however multiresistant bacteria were isolated.
We failed to find superiority of the intermittent operation mode of the suction tip over the continuous mode. A safe time frame before contamination of the suction tip occurs that could not be defined.
No preview · Article · Sep 2011 · Veterinary Surgery
[Show abstract][Hide abstract] ABSTRACT: To evaluate the effect of tibial tuberosity advancement (TTA) on patellofemoral (PF) contact mechanics, and alignment of the PF and femorotibial (FT) joints in cranial cruciate ligament (CrCL)-deficient stifles of dogs.
Ex vivo biomechanical study.
Unpaired cadaveric hind limbs (n=9).
Digital pressure sensors placed in the PF joint were used to measure contact force, contact area, peak and mean contact pressure, and peak pressure location with the limb under an axial load of 30% body weight and a stifle angle of 135°. The FT and PF poses were obtained using a 2-dimensional computer digitization technique. Each specimen was tested under normal, CrCL-deficient, and TTA-treated conditions. Data was normalized and analyzed, after testing for normality by Wilk-Shapiro, using 1 sample T-test, paired T-test, and ANOVA; P≤.05 was considered significant. Bonferroni's correction was used when needed.
A significant cranioproximal tibial displacement and increase in patellar tilt were found in the CrCL-deficient joints. Both FT and PF alignments were restored after TTA. Contact areas and peak pressure did not vary between conditions. Peak pressure location displaced proximally from intact to CrCL-deficient condition and returned to normal after TTA. Total force measured in the CrCL-deficient stifle and TTA conditions were significantly lower than in the control.
TTA restored the normal FT and PF alignment, and reduced the retropatellar force by about 20%.
Full-text · Article · Aug 2011 · Veterinary Surgery
[Show abstract][Hide abstract] ABSTRACT: To assess whether fully normalised vertical ground reaction forces and stance times obtained at a trot depend on dog breed or body conformations.
Peak vertical forces (PVF), vertical impulses (VI), stance times (ST), and ratio of forelimb impulse to total impulse (RVI) of 54 dogs of seven different breeds were normalised to body weight and body size according to the theory of dynamic similarity, and were tested for differences between breeds. Breeds were Borzoi, Bernese Mountain dog, Great Dane, Labrador Retriever, Landseer, Rhodesian Ridgeback, and Rottweiler. Body length ratio (BLR) and body mass index (BMI) were also compared between breeds.
Significant differences between breeds were found for the normalised forelimb PVF, VI and ST, and hindlimb PVF. Looking at individual breeds, it was most evident that Borzois had a lower forelimb VI, and a higher hindlimb PVF than the other breeds. This resulted in Borzois having a lower RVI compared to other dogs, indicating a more caudally located centre of gravity. Only a few differences in gait parameters were found between other dog breeds. The BMI was significantly lower in Borzois than in other breeds, but was otherwise not associated with gait parameters.
Force plate data of dogs of different breeds are not necessarily comparable, even after full normalisation to body weight and body size. Group comparisons should only be made when the groups consist of breeds with similar body conformations.
Full-text · Article · Jan 2011 · Veterinary and Comparative Orthopaedics and Traumatology
[Show abstract][Hide abstract] ABSTRACT: To retrospectively evaluate the outcome of internal fixation of trauma- related pelvic floor fractures using a ventral abdominal approach in cats.
Clinical examination and radiographic findings at presentation, after surgery, and at follow-up were assessed. Information gathered included concurrent injuries, surgical technique used, lameness and pain scores, and radiographic signs of implant stability.
Ten European shorthair cats were included in the study. Pelvic floor fractures were stabilised using locking plates in nine cats, and symphyseal separation was fixated using hemicerclage wire in one cat. Additional procedures included reduction of sacroiliac luxation in nine cats with positional screws placed in six cats, and plate stabilization of sacral fractures in one cat. All cats were able to walk within five days of surgery. No orthopaedic or neurological deficits were observed in seven cats at follow-up. Neurological deficits were observed in one cat. Signs of pain at implant sites due to inadequate surgical technique were noted in two cats. Anatomical reduction of the pelvic floor was achieved in eight cats.
Stabilization of the pelvic floor and repair of sacroiliac luxation and other injuries by a ventral abdominal approach in cats led to an overall successful outcome. Fixation of the pelvic floor in cats with intact acetabular and ilial bones should be considered in patients with multiple pelvic fractures in combination with sacroiliac joint luxation or sacral fracture, pelvic canal narrowing, traumatic abdominal hernia, and other abdominal injuries.
Preview · Article · Jan 2011 · Veterinary and Comparative Orthopaedics and Traumatology
[Show abstract][Hide abstract] ABSTRACT: Objective: To evaluate and compare healing, with and without the use of bone graft, of the gap created during tibial tuberosity advancement (TTA). Study Design: Prospective study and case series. Animals: Dogs treated with TTA (n=67). Methods: Prospective study: Mediolateral radiographic projections (6 weeks and 4 months) after TTA without use of bone graft (group I, n=14) were compared with radiographs of consecutive TTA in which the gap was filled with autologous cancellous bone graft (group II, n=14). Two scoring techniques (A, B) were used. Score A was used to grade the overall osteotomy healing (0=no healing, 4=healed osteotomy). Score B evaluated, independently of each other, healing in 3 sites: proximal to the cage (B1), between cage and plate (B2), and distal to the plate (B3). Case series: nongrafted TTA (4-25 weeks, n=39) were evaluated for healing (Score A). Data was analyzed using t-tests and ANOVA. Significance was set at P≤.05. Results: Prospective study: Score A, B2, and B3 showed no difference in healing between groups at 6.8 weeks and 4.2 months. Score B1 revealed, in both rechecks, a significantly higher density in group II. Case series: Radiographs at 11.59±5.99 weeks scored 3.3 (2-4). No healing related complications were observed. Conclusion: The osteotomy gap created during TTA healed within expected time regardless of bone graft use.
[Show abstract][Hide abstract] ABSTRACT: Objective: To evaluate and compare healing, with and without the use of bone graft, of the gap created during tibial tuberosity advancement (TTA).
Study Design: Prospective study and case series.
Animals: Dogs treated with TTA (n=67).
Methods: Prospective study: Mediolateral radiographic projections (6 weeks and 4 months) after TTA without use of bone graft (group I, n=14) were compared with radiographs of consecutive TTA in which the gap was filled with autologous cancellous bone graft (group II, n=14). Two scoring techniques (A, B) were used. Score A was used to grade the overall osteotomy healing (0=no healing, 4=healed osteotomy). Score B evaluated, independently of each other, healing in 3 sites: proximal to the cage (B1), between cage and plate (B2), and distal to the plate (B3). Case series: nongrafted TTA (4–25 weeks, n=39) were evaluated for healing (Score A). Data was analyzed using t-tests and ANOVA. Significance was set at P≤.05.
Results: Prospective study: Score A, B2, and B3 showed no difference in healing between groups at 6.8 weeks and 4.2 months. Score B1 revealed, in both rechecks, a significantly higher density in group II. Case series: Radiographs at 11.59±5.99 weeks scored 3.3 (2–4). No healing related complications were observed.
Conclusion: The osteotomy gap created during TTA healed within expected time regardless of bone graft use.
No preview · Article · Dec 2010 · Veterinary Surgery
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE: To evaluate the relationship of body weight (BW) and size, dog velocity, and vertical ground reaction forces (GRF) from a large number of dogs of various sizes.
STUDY DESIGN: Clinical research.
ANIMALS: Orthopedically healthy dogs (n=129)
METHODS: BW and dog size, represented as height at the withers (WH), were obtained. Stance times (ST), vertical impulses (VI), and peak vertical forces (PVF) of thoracic and pelvic limbs were measured on a force plate at controlled trotting speed. They were evaluated against BW and WH using linear regression analysis in absolute (nonnormalized) values, and when normalized to BW and/or body size according to the theory of dynamic similarity. Relative velocities were calculated for each dog.
RESULTS: Absolute ST, VI, and PVF showed strong positive correlations with BW and/or body size. When GRFs were normalized to BW, correlations with body size were markedly reduced, but remained positive for VI, and turned negative for PVF. Normalizing the time-dependent variables (ST and VI) also to WH eliminated most size influence. A small dependency of fully normalized GRF on body size remained that was because of differences in relative velocity between dogs of different sizes. Reference values for the fully normalized data are given.
CONCLUSIONS: The inherent relationship between BW, body size, dog velocity, and vertical GRF was demonstrated.
CLINICAL RELEVANCE: BW, body size, and relative dog velocity must be accounted for when wanting to obtain GRF variables that are comparable between different dogs.
[Show abstract][Hide abstract] ABSTRACT: A six-year-old, female, spayed Labrador Retriever was evaluated for progressive lameness of one year duration, ending in non-weight-bearing of the right hindlimb. The dog had a history of severe coxarthrosis of both hip joints, and had a HELICA hip prosthesis implanted in the right hip 18 months before. On survey radiographs, the acetabular and femoral components appeared unstable, with a large void in the proximal femur and a lacy periosteal reaction on the trochanter. Arthrocentesis was performed to rule out septic loosening. As culture samples were negative, the dog underwent surgery. We report the successful revision of an unstable HELICA screw hip prosthesis with a Zurich cementless total hip replacement. The patient had a good clinical and radiological outcome seven months postoperatively.
No preview · Article · Apr 2010 · Veterinary and Comparative Orthopaedics and Traumatology
[Show abstract][Hide abstract] ABSTRACT: To (1) evaluate radiographic changes associated with osteoarthrosis (OA) before and after tibial tuberosity advancement (TTA) and (2) determine if these changes are indicative of limb function as determined by kinetic gait analysis.
Prospective clinical study.
Dogs (n=35) with cranial cruciate ligament (CCL) deficient stifles (38).
Variables recorded were: complete or partial CCL rupture, meniscal lesions, arthroscopically graded cartilage lesions, complications, and revision surgeries. Radiographic evaluation and kinetic gait analysis (vertical ground reaction forces [GRFs]) were conducted pre- and 4-16 months postoperatively (mean, 5.9 months). Radiographs were evaluated without knowledge of operative findings and functional outcome. A score (0-3) based on new bone production at 11 specific sites was used to grade OA. Soft tissue changes were classified separately as normal or excessive. Preoperative scores were correlated with clinical variables. Postoperative scores and progression of OA scores were correlated with clinical variables and GRFs.
OA remained unchanged in 17 joints and progressed in 21 (55%). Dogs with meniscal lesions had higher OA scores preoperatively, but not at follow-up. Dogs with severe cartilage lesions at surgery had more progression of OA. GRFs improved after surgery and were not correlated with any of the radiographic OA scores.
Progression of OA was greater in the presence of severe cartilage lesions at surgery. OA scores were not correlated with GRFs.
Progression of OA is generally expected to occur after TTA despite improvement of limb function.
Full-text · Article · Mar 2010 · Veterinary Surgery