Modified transfixation pinning of compound radius and ulna fracture in a heifer

A 405-kg heifer sustained a compound fracture of the distal portion of the radius and ulna after being hit by a car. The fracture was thoroughly debrided, lavaged, and reduced with the heifer under general anesthesia. The fracture was immobilized with a modified walking cast, using 2 fully threaded 6.4-mm (outside diameter) Steinmann pins placed through the proximal portion of the radius. The pins were incorporated into a full-limb fiberglass cast, and a 0.5-cm X 2.25-cm aluminum walking bar was positioned medially and laterally on the limb. The modified walking cast was removed after 7 weeks, and the fracture healed without complication. The transfixation pins and aluminum walking bar helped reduce the strong compressive and rotational forces at the fracture site. The modified walking cast can potentially be used for fixation of a variety of fractures in large animals.     

一例泰迪犬桡尺骨骨折的诊断与治疗

文章对曾经临床收治诊疗的一例泰迪犬桡尺骨骨折的病例进行总结分析.患犬就诊时精神尚可,经过触诊和DR检查见右前肢遭到破坏、发生断裂,因此采取骨板内固定对桡尺骨完全断裂的患犬进行整复,内固定后利用DR诊断技术对桡尺骨的愈合情况作一系列评估.经过治疗,患犬愈后良好.文章为临床上犬桡尺骨骨折相关的诊疗提供参考.     

Fractures of the radius and ulna.

Fractures of the radius and ulna are common in the dog and cat. If treated inappropriately, complications may result. These include delayed union, nonunion, malunion, and growth deformities. ESF is a versatile method of fixation for fractures of the radius and ulna. Types that are applicable range from the simple type I to the complex type III fixator. In general, the more unstable the fracture, the more rigid the assembly must be to counteract fracture forces. There are three basic phases to consider when using ESF: (1) preoperative planning, (2) application of the ESF, and (3) long-term management. A deficiency in any one of these phases can lead to complications and an unsatisfactory clinical outcome. Although ESF can be used on many types of fractures, the technique is especially well suited for open or highly comminuted fractures when internal fixation is not applicable. In these cases, close attention must be paid to the integrity of the soft tissues. In addition, cancellous bone grafts should be placed either at the time of initial repair or in a delayed fashion after adequate vascularity has been established. Staged or complete removal of the ESF should be individualized to each fracture case. In general, staged disassembly or "dynamization" can begin when the bone and fixator begin to function as a composite as determined by radiographs. Complete fixator removal should be considered when the fracture exhibits clinical and radiographic evidences of union.     

Osteosarcoma of the proximal radius in a donkey

A mature donkey was presented for evaluation of a forelimb lameness and presence of a large mass on the left forelimb distal to the elbow joint. Clinical examination, radiographs and cytological examination of ultrasound‐guided fine needle aspirates of the mass led to a presumptive diagnosis of osteosarcoma. The donkey was subsequently subjected to euthanasia. Post mortem examination confirmed the diagnosis of osteosarcoma in the proximal radius with expansion of the mass through the ulnar cortex and metastases to liver and regional lymph nodes, areas of metastasis previously unreported in the equine literature.     

Osteolysis of the radius and ulna induced by a circumferential foreign body in a cat

CASE DESCRIPTION: A 1-year-old neutered male cat was examined because of a 6-month history of recurrent swelling and draining wounds affecting the craniomedial aspect of the distal portion of the left forelimb. CLINICAL FINDINGS: No lameness or neurologic deficits were evident. Examination of craniocaudal and lateromedial radiographic views revealed nonprogressive circumferential osteolysis and a mildly radiopaque, ring-shaped foreign body surrounding the radius and ulna. TREATMENT AND OUTCOME: During surgery, a tight elastic band surrounded by a thick fibrous tissue capsule was found encircling the limb. Microbial culture yielded a Staphylococcus sp that was susceptible to clindamycin. Follow-up monitoring via telephone communication with the owners 1.5 years after removal of the foreign body indicated that the cat had healed with no recurrence of drainage. CLINICAL RELEVANCE: Pressure osteolysis of the bones of the forelimb can be caused by a circumferential foreign body without associated neurologic abnormalities or lameness.     

Postnatal modelling of the humeroantebrachial contact areas of radius and ulna in dogs

Necropsy dogs (n = 234) ranging in age between 2 days and 17 years were examined to characterize the cross-sectional shape of the humeroantebrachial contact area of the radius and ulna on radioulnar scans of giant, large, mid-sized, small, and chondrodystrophic breeds. During growth, the contact areas became more circular in shape in all breeds, those in small dogs remained most elliptic. Smallest normalized heights (distance between the tip of the anconeal process and the most proximal aspect of the cranial margin of the radial head = RUH, distance between the tip of the anconeal process and the cranial tip of the medial coronoid process = UH) and depths (distance determined in a right angle to RUH = RUD, distance determined in a right angle to UH = UD) were noted in large and giant breeds with no significant difference between these. In juveniles, a decrease in UD was correlated with a decrease in UH in all breeds as was a decrease in RUD correlated with a decrease in RUH, whereas in non-arthrotic adults this condition could only be proven for mid-sized dogs and small breeds but not for giant, large and chondrodystrophic dogs. The average radioulnar and ulnar heights and depths (as seen in non-arthrotic adults) were calculated to be obtained in mid-sized dogs at least 3-4 weeks earlier than in large dogs. Lipping of the cranial margin of the radial head was significantly (P < 0.001) associated with lesion(s) of the articular surface (i.e. erosion of the articular cartilage and subchondral bone and/or fragmentation of the medial coronoid process) and caused additional change in shape of this contact area, which was then even more circular. However, the variables evaluated (RUH, RUD, UH, UD) allowed only poor discrimination between constitution types and between non-arthrotic and arthrotic joints.     

Asynchronous growth of the canine radius and ulna: effects of retardation of longitudinal growth of the radius.

After 2,000 rads of x-radiation to the right distal radial physis of eight 70-day-old dogs, the longitudinal growth of the right radius was retarded 42.1% when compared with the growth of the nonirradiated left radius. Asynchronous growth of the right radius and ulna resulted. The gross and radiographic changes that occurred over the subsequent 75 days were described. Subluxation of the humeroradial and humeroulnar joints occurred and was first observed 31 days after irradiation. By 75 days after irradiation, the radius was puller 7.8 mm distally by the radioulnar ligament. However, subluxation of the humeroradial joint was minimized by accelerated growth from the proximal radial physis and articular cartilage. Acceleration of growth also occurred at the distal radial articular cartilage. Growth from the distal ulnar physis and styloid process was retarded. It was thus apparent that after retardation of growth from the distal radial physis, considerable adjustment occurred in the relationship between the radius and the ulna and also in growth from their other physes, which reduced the deleterious effects of the growth retardation.     

Risk factors affecting metaphyseal irregularities in the radius and ulna of growing Newfoundland dogs

The main objective of this study was to study risk factors affecting metaphyseal irregularities (MI) in the distal radius and ulna of growing Newfoundland dogs. Risk factors studied included the genetic effects, effects of litters, BW, circumferences of the distal radius and ulna (CDRU), and total serum alkaline phosphatase (ALP) concentrations. The study included 118 Newfoundland dogs (60 females, 58 males), derived from 32 litters. Body weight, separated on sex and MI, was fitted to the Gompertz function. Occurrence of MI differed significantly between sexes, with 55% of males and 35% of females affected (P = 0.03). Growth curves for the 2 groups of dogs, with and without MI, diverged after 60 to 70 d, and dogs with irregularities were heavier at maturity than dogs of the same sex without irregularities. In univariate analysis, the litter effect was a significant predictor of MI, explaining 32% of total variability of the MI incidence, but the genetic effects were not significant. However, the latter were significant in bivariate analysis of MI and BW. In the bivariate analysis, the effects of litter on MI and BW were significantly correlated at all observational points except at birth, 180 d, and 536 d. Total ALP concentrations decreased with increasing age, and differences between groups diminished with increasing age, indicating a negative effect of total ALP on MI. Correlation between MI and total ALP concentrations of litters was estimated in a bivariate analysis. This correlation was significant and ranged between -0.34 and -0.62. Similarly, the genetic relationship between total ALP and MI from 120 d of age onward varied between -0.31 to -0.60. However, correlations were only significant at 356 d of age (genetic correlation = 0.60; P = 0.01). The mean CDRU increased from 90 d of age toward a peak at 180 d. Thereafter, CDRU declined and stabilized at about 1 yr of age. The mean CDRU between the groups of dogs with and without MI diverged most at 90 d of age, then was nearly stable until 180 d and gradually declined until 356 d, when the CDRU began to equalize. Metaphyseal irregularities and CDRU levels of litter were significantly correlated. Litter effect was a significant predictor of MI. The effects of litters and the genetic effects on BW and MI were correlated at most phases of the growth of the dog. Similar, but lower, correlations were found for CDRU and MI, and total ALP and MI.