Development of a lateral ultrasound-guided approach for the proximal radial,ulnar, median and musculocutaneous (RUMM) nerve block in cats

ObjectiveTo describe a lateral ultrasound (US)-guided approach to the radial, ulnar, median and musculocutaneous (RUMM) nerves through a single proximal in-plane insertion in cats and to determine whether one or two injection points are required to successfully stain all the target nerves.Study designProspective study.AnimalsA total of eight client-owned healthy cats and 12 cat cadavers.MethodsIn live cats, the US anatomy of the brachium, the landmarks and the site for needle accesses were determined. Then, 12 thawed feline cadavers were used to assess the spread of dye solution and nerve staining following the US-guided proximal-lateral-humeral RUMM injection using one and two injection points. Each cadaver was injected with 0.15 mL kg^–1 of a 0.25% new methylene blue solution in either a single injection aimed for the radial nerve of one limb (G1) or via two sites delivering 0.1 mL kg^–1 and 0.05 mL kg^–1 aimed for the radial and musculocutaneous nerves of the opposite limb, respectively (G2). Upon dissection, staining of the target nerves around their circumference for length of >1 cm was considered successful.ResultsSonoanatomy was consistent with anatomy upon dissection and target nerves were identified in all cadavers. Staining was 100% successful for the radial, median and ulnar nerves in both groups, and 41.7% and 100% for the musculocutaneous nerve in G1 and G2, respectively.Conclusions and clinical relevanceThis novel lateral US-guided approach for the proximal RUMM nerve block allowed a good identification of the nerves and related structures, and it provided a consistent muscular structure through which the needle could be easily guided. An injection performed in two aliquots (within the caudal and cranial compartments of the neurovascular sheath) appeared to be necessary to successfully stain all the target nerves.     

Fractures of the proximal sesamoid bones in thoroughbred foals.

Eighteen cases of fractures of the proximal sesamoid bones in Thoroughbred foals are described. Most of the fractures were in foals under 2 months old and all but one occurred in the forelegs. The bones commonly fractured when the foal galloped to exhaustion trying to keep up with its dam in the paddock. The types of fracture varied but a simple fracture of the medial sesamoid was most frequent and the majority were towards the base of the bone. Six foals sustained a fracture of more than one sesamoid bone and one foal fractured all 4 proximal sesamoid bones in its front legs. Treatment included box rest and the surgical removal of the separated piece of sesamoid bone. Only 3 of the foals treated have raced. One of these was treated surgically.     

Age-related changes for serum bone metabolism markers in thoroughbred and quarter horse foals

Serum bone specific alkaline phosphatase (BALP) and osteocalcin were measured in 9 Thoroughbred and 4 Quarter Horse (QH) foals. Eight were colts, and 5 were fillies. The first blood sample was collected from foals between 10 and 14 hours after birth on day 1. Blood then was collected on days 3, 6, 9, 12, 15, 18, 21, 28, 35, 42, 49, 56, 70, 84, 98, and 112 between 7:00 and 9:00 am. Serum bone metabolism marker raw data were analyzed with analysis of variance with repeated measures over time with gender and breed in the model. Average serum osteocalcin concentrations were higher for Thoroughbred than QH foals: 152.1 ± 4.6 ng/mL and 131.3 ± 6.3 ng/mL (mean ± standard error), respectively (P = .01). No overall differences were seen for gender (P = .10). However, on day 1, colts had higher osteocalcin than did fillies at 199.6 ± 30.2 ng/mL and 93.8 ± 32.4 ng/mL, respectively (P = .04). Thoroughbred foals had higher average serum BALP concentrations than did QH foals, with average values of 260.8 ± 13.4 U/L and 205.1 ± 18.5 U/L, respectively (P = .02). No gender differences were seen for serum BALP (P = .48). Serum carboxy-terminal propeptide of Type I procollagen (PICP) concentrations could not be measured in this study because the Metra Biosystems assay for PICP could not be validated.

Introduction

Bone synthesis by the osteoblast can be divided into 3 phases: proliferation, matrix development and maturation, and mineralization.¹ Gene expression of type I collagen takes place during the proliferation of the osteoblast cells. The expression of bone specific alkaline phosphatase (BALP) reaches its maximum during matrix maturation and declines as matrix mineralization starts. The osteocalcin gene is expressed during matrix mineralization.When type I collagen is produced as procollagen and released into the extracellular space, the amino and carboxyterminal propeptides of type I procollagen (PINP and PICP, respectively) are cleaved off.² Serum PICP has been shown to be a good marker for bone formation in metabolic bone diseases.³ In Thoroughbred fillies, PICP has an inverse relationship with age, with highest values found in animals less than 1 year of age.⁴ Serum alkaline phosphatase (ALP) has been measured in the young foal and is highest at birth, decreasing to a constant level by 2 months of age.^{5, 6 and 7} Serum BALP constitutes 60% to 92% of the total serum ALP in the horse and is highest in the foal.^{4 and 8} As the foal matures, there is an inverse relationship between age and serum BALP.^{4 and 9} Serum osteocalcin in foals less than 6 months of age has not been reported as having the same age-related pattern as serum BALP.¹⁰However, younger horses have higher serum osteocalcin values than mature horses.^{11, 12 and 13} Davicco et al¹⁴ showed plasma osteocalcin age-related changes for Thoroughbred foals with radioimmunoassay (RIA). Plasma osteocalcin was low at birth, increased to day 8, and then dropped to day 15. The objective of this study was to establish normal ranges and age-related changes in serum BALP, PICP, and osteocalcin in the foal with enzyme-linked immunospecific assays (ELISAs).

Materials and methods

Four Quarter Horse (QH; 2 fillies and 2 colts) and 9 Thoroughbred (3 fillies and 6 colts) foals were included in the study from birth through 112 days of age. Foals were born from February 5 to May 13, 1998. Mares and foals were housed on 40 acres of Bahiagrass (Paspalum notatum) pasture and fed a 15% crude protein (as fed) sweet feed. Body scores were recorded every 28 days on a scale from 1 to 9.¹⁵ Concentrate was fed to each mare at 1.5 kg/100 kg body weight daily and was increased by 20% for each body condition score below 5 and decreased by 20% for each body condition score above 5. Mares were individually fed in 3.6 × 3.6—m stalls twice daily, with foals allowed access to the mares feed. Trace mineral salt blocks were available in the pastures. Water was available at all times.Blood was collected from foals between 10 and 14 hours after birth on day 1. Blood then was collected on days 3, 6, 9, 12, 15, 18, 21, 28, 35, 42, 49, 56, 70, 84, 98, and 112 after morning feedings. Except for day 1, all blood samples were collected between 7:00 and 9:00 am. All blood samples were collected with jugular venipuncture into a glass vacutainer containing no additives or anticoagulants and were allowed to clot. Serum was separated and frozen at −20°C within 4 hours of collection. All samples were analyzed within 6 months of collection.The Alkphase-B immunoassay for the determination of BALP (Metra Biosystems, Mountainview, Calif) and the NovoCalcin immunoassay for determination of osteocalcin (Metra Biosystems), used in this study, have been previously validated in the horse.^{16 and 17} The Prolagen-C immunoassy for determination of the PICP (Metra Biosystems) has not been previously validated in the horse.¹⁷Serum bone metabolism marker raw data were analyzed with analysis of variance with repeated measures over time with gender and breed in the model. Analyses were performed with Statistical Analysis System with proc glm for the analysis of variances.¹⁸

Results

Average serum osteocalcin concentration for the testing period was higher for Thoroughbred than QH foals: 152.1 ± 4.6 and 131.3 ± 6.3 ng/mL (mean ± standard error), respectively (P = .01). No overall differences were seen for gender (P = .10). However, on day 1, colts had higher osteocalcin concentrations than did fillies at 199.6 ± 30.2 ng/mL and 93.8 ± 32.4 ng/mL (P = .04; Fig 1).

Compression plating of radial and ulnar fractures in the goat.

Internal fixation of radial and ulnar fractures in three goats was accomplished using bone plates. Intervals between the time of fracture and internal fixation varied from one to 13 days. The goats were ambulatory the day after surgery, and recoveries were uneventful.     

A comparison of subjective and quantitative methods for detection of physitis in Thoroughbred foals

AIM: To compare subjective and quantitative methods of assessing physeal swelling of the distal third metacarpal (Mc3) and metatarsal (Mt3) bones of Thoroughbred foals. METHODS: The fetlocks of 16 Thoroughbred foals were filmed on five occasions over a period of 5 months and the video images were transferred to computer and digitised. The rate of change of each of the medial and lateral contours of the distal Mc3 and Mt3 bones was determined by calculating values for the second derivative of the contour. The degree of physeal swelling at the same site was subjectively assessed and allocated a grade based on an ordinal scale of severity. The maximum value for the second derivative was compared with the grade of physeal swelling. RESULTS: The second derivative values for sites with slight to distinct physeal swelling (Grade >/=1.5) were significantly higher (p=0.001) than the second derivative values for sites with no apparent physeal swelling (Grade 0). CONCLUSION: This finding indicates that the value of the second derivative of the contour of a limb has potential as a diagnostic tool for quantitative detection of physitis.     

Use of microsatellite markers to detect quantitative trait loci in Yorkshire pigs

To identify genetic markers associated with economic traits in pigs, 157 microsatellite markers were examined in Yorkshire pigs. Thirty eight female Yorkshire pigs were initially examined and six of them were selected as progenitors; half were more than 1.5 standard deviations (SD) above the mean for average daily gain (ADG) and backfat thickness (BFT), and the remaining half were more than 1.5 SD below the mean. These pigs were then mated to male Duroc pigs, and 200 F2 pig offspring were examined for the association of specific alleles with ADG and BFT. To confirm the specific markers identified in the initial analysis, associations of significant markers with economic traits were further examined in 228 additional performance-tested purebred pigs. Twenty-five microsatellite markers were significantly associated with either ADG or BFT, and among these, 17 were associated with both traits. The markers with the highest association to ADG were also associated with BFT. Our study reveals that specific markers could be used to predict economic significance, and confirms several quantitative trait loci (QTL) identified in previous studies. However, further analysis with more closely-spaced microsatellite markers is required to refine predictive values for economic traits and positions of QTL that are reliable for actual phenotypic prediction.     

Effect of two different nutritional programs on orthopedic alterations in mangalarga marchador foals

This study was carried out to verify the effects of two nutritional programs (TA: supplementation with concentrate plus mineral mix between two and 12 months of age, and TB: supplementation with concentrate plus mineral mix from weaning at 165 days of age to 12 months on growth parameters in 22 Mangalarga Marchador foals. Data recorded were: cortical index (CI), time of epiphyseal cartilage closure of distal metacarpus and proximal phalange, epiphysitis and flexural deformity occurrences and weight/height ratio (W/H). Body measurements were taken monthly and radiographs every two months. Animals were born from September 1993 to February 1994 and were allocated to treatments according to the following criteria: each two subsequent foals of the same sex, from the same stallion were randomly assigned to opposite treatments. Data from the randomized block design were submitted to analysis of variance and their means compared by F test. TA foals showed less epiphysitis until 272 days of age and better CI from 228 days on. W/H up to 2:1 did not influence epiphysitis occurrence. Feed restriction (TB) delayed epiphyseal cartilage closure of distal metacarpus and proximal phalanx. No flexural limb deformity was observed in foals on either treatment.     

Measurement of serum IgG in foals by radial immunodiffusion and automated turbidimetric immunoassay

Hypogammaglobulinemia as a result of failure of transfer of passive immunity (FTPI) is an important risk factor for infectious disease in neonatal foals. The current gold standard for determining serum immunoglobulin concentrations is radial immunodiffusion (RID). The purpose of this study was to compare immunoglobulin concentrations measured by RID with those determined by an automated turbidimetric immunoassay (TIA), which has a much shorter turnaround time. Immunoglobulin concentrations were measured by both RID and TIA in serum collected from 84 neonatal foals. Sixty-seven foals had results within the linear range for both assays. Sensitivity and specificity of TIA for diagnosis of FTPI with IgG < or = 800 mg/dL were 0.81 (95% CI 0.70-0.88) and 0.86 (95% CI 0.76-0.93) and with IgG < or = 400 mg/dL were 0.63 (95% CI 0.35-0.86) and 0.92 (95% CI 0.87-0.95), respectively. A significant linear relationship was found between IgG concentrations determined by TIA and RID (TIA = 0.9511RID + 8.4354; R2 = .59, P < .0001). The coefficients of variation for between-run and within-run precision for the TIA were 2.5 and 3%, respectively. Storage of samples from 10 foals at -20 degrees C for 10-12 months resulted in a reduction in TIA-measured serum IgG concentration of -17.6% (SD = 3.7%), indicating that long-term storage of samples at -20 degrees C should be avoided. The results of this study indicate that measurement of serum IgG by TIA can be used to evaluate foals for FTPI.     

Bone dysplasia in the radial and ulnar metaphysis of a Newfoundland dog

A recently described metaphyseal irregularity of the radius and ulna was diagnosed radiographically in a significant proportion of Newfoundland dogs during the course of a large study. This case report describes the pathological picture of a Newfoundland dog with these radiographic changes. The lesions in the distal radius and ulna were characterized by focal, longitudinal striations of sclerosis of the bone marrow cavity, surrounding thin trabeculae of primary spongiosa of the distal metaphysis. It is suggested that these lesions represent a sclerosing dysplasia not previously described in dogs, but with some similarities to the human disorder, osteopathia striata.     

Biomechanical comparison of cortical radial graft versus ulnar transposition graft limb-sparing techniques for the distal radial site in dogs

OBJECTIVE: To compare the biomechanical properties of radial graft (RG) versus ulnar transposition graft (UTG) limb-sparing techniques in the dog. STUDY DESIGN: Cadaveric study. ANIMALS: Six pairs of normal canine thoracic limbs. METHODS: In each pair of limbs, 1 limb was subjected to the RG technique and the other to the UTG technique. Limbs were tested in axial loading until failure. Modes of failure and biomechanical properties were compared between the 2 groups. Percent coverage of the metacarpal bone by the plate was retrospectively compared between the limbs that failed by fracture of the metacarpal bones and those that did not. RESULTS: RG limbs had significantly greater stiffness, yield load, maximum load, maximum energy, and post-yield energy. All UTG limbs failed by cranial bending of the plate. Half of the RG limbs failed by caudal bending of the plate and half by fracture of the third metacarpal bone at the distal end of the plate. Limbs with <80% plate coverage of the metacarpal bone were significantly more likely to fail by metacarpal fracture. CONCLUSIONS: The RG technique was biomechanically superior to the UTG technique under the conditions studied. At least 80% plate coverage of the metacarpal bone should be achieved. CLINICAL RELEVANCE: Exercise restriction and coaptation bandages should be considered for patients undergoing the UTG technique to minimize potential biomechanical complications.     

Use of quantitative two-dimensional color tissue Doppler imaging for assessment of left ventricular radial and longitudinal myocardial velocities in dogs

OBJECTIVE: To determine left ventricular free wall (LVFW) radial and longitudinal myocardial contraction velocities in healthy dogs via quantitative 2-dimensional color tissue Doppler imaging (TDI). ANIMALS: 100 dogs. PROCEDURE: TDI was used by a single trained observer to measure radial and longitudinal myocardial movement in the LVFW. Radial myocardial velocities were recorded in segments in the endocardial and epicardial layers of the LVFW, and longitudinal velocities were recorded in segments at 3 levels (basal, middle, apical) of the LVFW. RESULTS: LVFW velocities were higher in the endocardial layers than in the epicardial layers. Left ventricular free wall velocities were higher in the basal segments than in the middle and apical segments. Radial myocardial velocity gradients, defined as the difference between endocardial and epicardial velocities, were (mean +/- SD) 2.5 +/- 0.8 cm/s, 3.8 +/- 1.5 cm/s, and 2.3 +/- 0.9 cm/s in systole, early diastole, and late diastole, respectively. Longitudinal myocardial velocity gradients, defined as the difference between basal and apical velocities, were 5.9 +/- 2.2 cm/s, 6.9 +/- 2.5 cm/s, and 4.9 +/- 1.7 cm/s in systole, early diastole, and late diastole, respectively. A breed effect was detected for several systolic and diastolic TDI variables. In all segments, systolic velocities were independent of fractional shortening. CONCLUSIONS AND CLINICAL RELEVANCE: LVFW myocardial velocities decreased from the endocardium to the epicardium and from base to apex, thus revealing intramyocardial radial and longitudinal velocity gradients. These indices could enhance conventional echocardiographic analysis of left ventricular function in dogs. Breed-specific reference intervals should be defined.     

Vascularized ulnar bone grafts for limb-sparing surgery for the treatment of distal radial osteosarcoma

The objective of this retrospective study was to compare vascularized free or roll-in ulnar bone grafts for limb-sparing surgery in dogs with radial osteosarcoma with the cortical allograft, metal endoprosthesis, or distraction osteogenesis techniques. Overall, the ulnar graft techniques used in this study demonstrated excellent healing properties. Complications included recurrence of the tumor in 25% (2/8) of the dogs, metastasis in 50% (4/8) of the dogs, implant loosening in 37.5% (3/8) of the dogs, implant failure in 12.5% (1/8) of the dogs, and infection in 62.5% (5/8) of the dogs. Mean survival time was 29.3 mo (range, 9 to 61 mo). The mean metastasis-free interval was 33.67 mo (range, 8 to 54 mo). Tumors recurred locally in two dogs at 10 mo and 20 mo postoperatively. This study yielded similar long-term complications as other limb-sparing options (such as cortical allografts and metal endoprostheses) and allowed dogs to bear weight on the operated limb with acceptable limb function. More research is needed regarding specific healing times for ulnar vascularized grafts, time until implant removal, and the extent of radial bone that could ultimately be replaced by the ulna.     

A technique for the management of radial and ulnar fractures in miniature dogs using translation pins

Fractures of the distal third of the radius and ulna of miniature dogs frequently suffer the complication of non-union. Techniques for the management of such fractures are generally adaptations of those used in larger dogs. The successful treatment of three cases is reported, utilising transfixation pins and acrylic cement.