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Summary The behaviour of cortical bone under load is strain rate-dependent, i.e. it is dependent on the rate at which the load is applied. This is particularly relevant in the galloping horse since the strain rates experienced by the bone are far in excess of those recorded for any other species. In this study the effect of strain rates between 0.0001 and 1 sec-1 on the mechanical properties of equine cortical bone were assessed. Initially, increasing strain rates resulted in increased mechanical properties. Beyond a critical value, however, further increases in strain rate resulted in lower strain to failure and energy absorbing capacity. This critical rate occurred around 0.1 sec−1 which is within the in vivo range for a galloping racehorse. Analysis of the stress-strain curves revealed a transition in the type of deformation at this point from pseudo-ductile to brittle. Bones undergoing brittle deformation are more likely to fail under load, leading to catastrophic fracture and destruction of the animal.

Summary A transmission electron microscope study was undertaken to investigate the details of the synovial tendon sheath and bursal lining in horses. The lining cells appeared to be fibroblasts and were buried in a finely granular ground substance. Generally these cells had poor cytoplasmic organelles, sparse short profiles of rough endoplasmic reticulum (RER), few scattered ribosomes and, occasionally, a poorly developed Golgi complex. However, a few lining cells appeared more active, having pronounced RER with dilated cisternane. The surface of the lining cells, particularly those with dilated RER, had filipodia of different shapes, which in some instances appeared to surround a detached matrix. This feature might indicate that these cells are capable of phagocytosis. In young animals, the lining was more or less akin to that of the adult. However, the lining cells were virtually indistinguishable from the fibroblasts in the subconnective tissue.

One normal cadaver specimen and six labrador retrievers with suspected elbow osteochondrosis were examined using a microfocal radiographic technique as an aid to diagnosis. This allowed the production of a magnified image (macro-radiograph) with high spatial resolution. The macroradiographs were compared with radiographs obtained using a standard technique to see if they facilitated decision making with respect to case management. The lesions that were suspected from radiographic examination were correlated with the gross lesions found at elbow arthrotomy. Microfocal radiography gave additional information about the changes within the joints but it still remained difficult to image the lesion satisfactorily in some cases.

Reasons for performing study Injury to the superficial digital flexor tendon (SDFT) is common in equids, with a high risk of re-injury associated with changes in tendon stiffness. In vivo measurement of limb stiffness has been shown to correlate with tendon stiffness after injury [1] but requires kinematic analysis which is impractical in a clinical setting. We have developed a simple system for measuring limb stiffness statically, which could be used as a tool for monitoring SDFT healing. Objectives To validate a goniometric measurement of limb stiffness. Study design Cross sectional study. Methods Initially, forelimb stiffness indices were determined at the walk for 6 equids using a validated kinematic analysis [1]. Limb stiffness indices were then calculated using portable floor scales to record ground reaction force (GRF), and an electrogoniometer to record metacarpophalangeal joint angle. Goniometric limb stiffness indices were subsequently measured in 11 horses ranging from 2 to 20 years of age, with no clinical evidence of SDFT injury. Strength and significance of correlation and agreement between the measurement methods was assessed and association between limb stiffness, limb (left vs. right), weight and age of horse and were calculated. Results There were strong positive correlations between GRF and joint angle (R2 = 0.98) and between the static and kinematic methods (R = 0.78, P

Mechanical test specimens were prepared from the cranial and caudal cortices of radii from eight horses. These were subjected to destructive tests in either tension or compression. The ultimate stress, elastic modulus and energy absorbed to failure were calculated in either mode of loading. Analysis was performed on the specimens following mechanical testing to determine their density, mineral content, mineral density distribution and histological type. A novel technique was applied to sections from each specimen to quantify the predominant collagen fibre orientation of the bone near the plane of fracture. The collagen map for each bone studied was in agreement with the previously observed pattern of longitudinal orientation in the cranial cortex and more oblique to transverse collagen in the caudal cortex. Bone from the cranial cortex had a significantly higher ultimate tensile stress (UTS) than that from the caudal cortex (160 MPa vs 104 MPa; P < 0.001) though this trend was reversed in compression, the caudal cortex becoming relatively stronger (185 MPa vs 217 MPa; P < 0.01). Bone from the cranial cortex was significantly stiffer than that from the caudal cortex both in tension (22 GPa vs 15 GPa; P < 0.001) and compression (19 GPa vs 15 GPa; P < 0.01). Of all the histo-compositional variables studied, collagen fibre orientation was most closely correlated with mechanical properties, accounting for 71% of variation in ultimate tensile stress and 58% of variation in the elastic modulus. Mineral density and porosity were the only other variables to show any significant correlation with either UTS or elastic modulus. The variations in mechanical properties around the equine radius, which occur in close association with the different collagen fibre orientations, provide maximal safety factors in terms of ultimate stress, yet contribute to greater bending of the bone as it is loaded during locomotion, and thus lower safety factors through the higher strains this engenders.

Summary The structure of equine synovial tendon sheaths and bursae has been examined by light and scanning electron microscopy. Tissue samples were obtained from horses of various types and ages with no clinical evidence of sheath or bursal disorders. The interior of both structures was lined by a cellular layer superimposed on a vascular zone supported by a fibrous layer. The pattern of cell distribution of the lining varied from site to site within the same structure depending on the nature of the underlying tissue and on the amount of movement to which the structure was subjected. The cellular layer was predominantly fibrous in nature with scanty, widely separated fibroblasts (eg where it lines the palmar ligament, tendons and paratendons). In the mesotendon and bursal extremities, where the lining is subjected to a positive degree of movement, the cellular layer was areolar in type with well established folds populated by abundant cells oval to round in shape. In foals and yearlings, the supportive layer was mainly around the areolar with patches of adipose tissue; which were gradually replaced by fibrous tissue as the animal grew.

With advancing years a dog may suffer from a variety of conditions of its musculoskeletal system which adversely affect its ability to exercise and may cause it to be retired from activities in work and sport for which it has been trained. Arthritis is common, and in many cases arises from developmental errors suffered in puppyhood, such as hip dysplasia, osteochondrosis and growth plate disorders. Trauma to joints (ligament ruptures, dislocations and fractures) may also be the precursor of degenerative joint changes later in life. It is important, therefore, for all such conditions to be corrected as effectively as possible if joint disease is to be minimised as the dog grows older. Preventive action is also required for some conditions for which correction may not be entirely feasible, so the identification of modes of inheritance is important if those are to be controlled by breeding. Certain spinal disorders also tend to increase in prevalence with age, particularly spondylosis deformans, neoplasms and chronic degenerative radiculomyelopathy. As it happens, spondylosis in mild to moderate degree affects pet dogs very little, but a reduction in spinal flexibility can cause problems for dogs required to be agile in work or sport. In common with other body tissues, neoplasm of the locomotor system increases in occurrence in older dogs, and although the overall incidence of tumours of bones, joints, nervous tissue and muscle is relatively low, these are the most serious of all the limb and spinal conditions encountered because of their life threatening propensities. The treatment required covers a wide range from simple changes of management in order to reduce exercise, to the use of analgesics and anti-inflammatory drugs and to surgery to remove diseased tissue, stabilise joints or reduce pain with forms of arthroplasty or arthrodesis.

A flexural deformity affecting one or both forelimbs identified in 21 puppies of six to 12 weeks of age closely resembled a condition which has long been known in foals and farm animals at birth or shortly afterwards. In the puppies the characteristic feature was carpal hyperflexion which was associated with tautness of the tendons of the flexor carpi ulnaris muscle. The majority recovered spontaneously with conservative management but in two puppies it was necessary to section the shortened tendons to enable a normal limb posture to be regained. The fact that there was a preponderance of dobermann pinschers (17 out of 21) in the group opens speculation about an hereditary factor being involved, but further study is needed before such a correlation can be reached.

The effects of peroneal neurectomy at different nerve levels in the dog and cat are described. The resultant limb paralyses were considerably improved by the application of a muscle relocation technique, transferring either the long digital flexor or caudal tibial muscle. The results of combined peroneal and tibial neurectomy as well as nerve root sectioning (L6, L7) are also described.

An account is given of some of the complications that arise following the internal fixation of fractures in dogs. Osteomyelitis is one of the most serious untoward sequelae and the clinical and radiographic features of twenty-five dogs with the severe form are described. Treatment by means of debridement, further fracture immobilization and antibiotic therapy proved successful in the majority. Stifle joint stiffness following the repair of femoral fractures is discussed, and attention is drawn to a number of problems that are caused by errors of technique.

Pectineus muscle resection was performed on 100 dogs with hip dysplasia. The degree of dysplasia was estimated by radiography and by joint manipulation. The effects of the procedure on 81 dogs were determined by personal reinspection (34), or by means of owner-reports (47). Improvement was noted in 80 per cent but only 35 per cent reached a high level of recovery. The operation has a role in the treatment of hip dysplasia but it does not cure the condition and it will be several years before the long-term results are known.

Implants of plaited carbon fibre have been used in the repair of ruptured Achilles tendons in ten dogs. Additionally the hock was held in extension by inserting a screw through the fibular tarsal bone and the tibia. When the screw was removed in the sixth week the repaired tendon was thick and taut, and leg use was thereafter virtually normal.

An account is provided of the management of 68 dogs with tendon injury. Of the 33 with Achilles rupture, 23 sustained tendon severance, seven had disrupted the gastrocnemius muscle/tendon junction, and in three an attachment of the gastrocnemius was avulsed. The standard operative procedure comprised fixing the hock in extension with a screw, and exploring the damaged structures with a view to repair and the introduction of carbon fibre implants. The majority regained normal limb use and the main complications concerned loosening or fracture of the screw. The 32 with digital flexor tendon severance had cuts, on a fore foot in nine and a hind foot in 23. Exploration and reconstruction were routinely practised and carbon fibre implants were frequently used. The standard of recovery was good in those dealt with fresh but was less satisfactory in chronic cases. The two dogs with digital extensor tendon and the one with flexor carpi ulnaris tendon severance responded well to repair.

The conditions described fall into three categories: (1) muscle contractures (mm. infraspinatus, gracilis and quadriceps); (2) avulsion and displacement of muscles and tendons; and (3) severance of tendons (Achilles, digital flexors). The clinical features and treatment are outlined for each condition mentioned, and aspects of aetiology are discussed. The approach essential to the satisfactory repair of severed tendons is presented and the techniques employed for primary and secondary suturing are described. An account is also given of the use being made of carbon fibre implants in the repair of tendon injuries.

The fore and hind feet of 50 unselected Rottweilers were examined clinically and radiographically for abnormalities of their volar and plantar sesamoid bones. Lesions were found in 22 (44 per cent), invariably affecting the No. 2 and/or No. 7 sesamoids. The majority occurred in the forelimb. Clinical signs were detected in only five dogs and local analgesia in these cases indicated that the sesamoid changes were not the cause of the presenting lameness. Radiographically the defect varied from small radiodense foci separated from an otherwise normal sesamoid, to gross distortion of the bone into a number of calcified bodies. In none of these dogs was the sesamoid abnormality demonstrated to cause lameness and it was not necessary, therefore, to treat the condition surgically. It is postulated that these lesions result from disordered ossification with subsequent degenerative changes.

In a 4-year period nine dogs have been met in which there was incomplete growth of the radius. The condition was unilateral in eight dogs and bilateral in one. Two were littermates. The defect is due to premature cessation of growth of the distal growth plate of the radius but the cause of this is not precisely known. It is recognized by characteristic radiographic changes in radius length, elbow joint space and premature closure of the distal growth plate of the radius. A method of surgical treatment has been devised and has proved beneficial in five dogs. Zusammenfassung. In einer Vierjahresperiode wurden neun Hunde beobachtet, bei denen ein unvollstandiges Wachstum des Radius vorlag. Bei acht Hunden war der Zustand nur auf einer Seite zu finden, bei einem Hund auf beiden Seiten. Zwei der Hunde gehorten zum gleichen Wurf. Der Mangel ist auf verfruhte Wachstumseinstellung der distalen Wachstumsplatte des Radius zuruckzufuhren, jedoch ist die Ursache davon nicht genau bekannt. Er wird an charakteristischen radiographischen Veranderungen der Radiuslange, des Ellbogengelenkzwischenraums und vorzeitigem Abschluss der distalen Wachstumsplatte des Radius erkannt. Es wurde eine chirurgische Behandlungsmethode entwickelt, die sich bei funf Hunden als nutzlich erwies. Resume. Au cows d'une periode de 4 ans on a observe 9 cas de croissance incomplete du radius chez des chiens; l'anomalie etait unilaterale dans 8 cas et bilaterale dans un cas; deux chiens appartenaient a la meme portee. L'anomalie est due a l'arret premature de croissance de la plaque de croissance distale du radius, mais la cause n'en est pas encore connue d'une maniere precise. Le diagnostic se fait par les signes radiologiques caracteristiques, modifications de la longueur du radius, de l'articulation du coude et soudure prematuree de la plaque de croissance du radius. On a elabore une methode de traitement chirurgical, qui s'est montree favorable chez 5 chiens.

The authors record their experiences of the surgical treatment of twenty-one unilateral and thirteen bilateral cases of osteochondritis dissecans of the humerus of the dog. The operative technique and the clinical pathology of the condition are described. In nearly all cases there was complete restoration of limb function within 3 months of surgery; this is a much better result than that obtained in a previous series treated conservatively. Nineteen of the affected dogs had signs of hip dysplasia. Resume. Les auteurs rapportent leurs experiences concernant le traitemerit chirurgical de 21 cas unilateraux et de 13 cas bilateraux d'osteochondrite dissecante de l'humerus du chien. On decrit les techniques operatoires et les donnees de l'examen clinique. Dans presque tous les cas, on a obtenu une restauration presque complete de la fonction du membre dans les 3 mois qui ont suivi l'operation, ce qui represente un resultat nettement superieur a celui obtenu dans des series precedentes traitees par un mode conservateur. Dix-neuf des chiens atteints ont presente des signes de dysplasie de la hanche. Zusammenfassung. Die Autoren geben ihre Erfahrungen mit der chirurgischen Behandlung von 21 einseitigen und 13 beidseitigen Fallen von Osteochondritis dissecans des Humerus des Hundes bekannt. Die Operationstechnik und die klinische Pathologie des Zustands werden beschrieben. In fast allen Fallen wurde die vollstandige Wiederherstellung der Extremitatenfunktion innerhalb von drei Monaten nach dem chirurgischen Eingriff erreicht; dies ist ein viel besseres Ergebnis, als mit einer fruheren Reihe von Fallen durch konservative Behandlung erzielt wurde. Neunzehn der erkrankten Hunde wiesen Anzeichen von Huftdysplasie auf.

— The study includes the examination and treatment of twenty dogs with a non-union fracture of the shaft of a limb bone. Eighteen dogs were of the small breeds. The fracture had occurred in the distal third of the radius/ulna in twelve, the tibia in five and the femur in three. All the fractures healed satisfactorily following surgical repair in which the bone ends were cleaned of fibrous tissue, realigned, and secured in position with plates and screws. Resume— L'etude comprend l'examen et le traitement de vingt chiens avec une fracture non consolidee du corps de 1'0s d'un membre. I1 y avait dix-huit chiens des races petites. La fracture s'est produit au tiers distal du radiusicubitus en douze des chiens, elle s'est produit au femur en trois des chiens. Tous les fractures se guerissent de facon satisfaisante apres les reparations chirurgic aux quand le tissue conjonctif a enleve des bouts des os, on les a mis en ligne, et on les a immobilise avex des planches et des vis. Zusammenfassung— Die Studie beinhaltet die Untersuchung und Behandlung von zwanzig Fallen von Extremitatenfrakturen bei Hunden, welche Tendenz zur Nicht-Vereinigung der Bruchenden zeigten. Achtzehn Fallen ereigneten sich bei Hunden, welche kleineren Rassen ange-horten. In zwolf Fallen ereignete sich der Bruch im distalen Drittel des Radius und der Ulna, in funf Fallen war die Tibia betroffen und in drei Fallen der Femur. Alle diese Bruche heilten zufrieden-stellend nach chirurgischer Behandlung und nachdem die Bruchenden vom fibrosen Gwewebe gereinigt wurden, in korrekte Position gebracht, und mit Platten und Schrauben gesichert wurden.

— A review is presented of thirty cases, in the dog, where repair of rupture of the anterior cruciate ligament was undertaken using skin as a ligament substitution material. The results of this series are examined and the authors recommend the employment of whole thickness skin grafts for cruciate ligament replacement. Resume— Une etude est presentee de trente cas de reparation de la rupture du ligament croise anterieur chez le chien, utilisant la peau come materiel de substitution de tissu ligamentaire. Les resultats obtenus dans ce groupe sont etudies et les auteurs recommandent l'emploi de greffes de peau entiere pour le remplacement de ligaments croises. Zusammenfassung— Es werden dreissig Falle beschrieben, in denen bei Hunden ein Riss des vorderen Kreuzbandes unter Verwendung von Haut als Ligamenturnersatz ausgebessert wurde. Die Ergebnisse dieser Serie wurden untersucht, und die Autoren empfehlen, Hauttransplantate ganzer Dicke zur Ausbesserung des gerissenen Kreuzbandes zu verwenden.

— The advantages and disadvantages of various methods of sterilization of surgical materials are reviewed. The methods discussed are boiling, hot air, steam under pressure, chemicals and gamma rays. Resume— Les avantages et desavantages des differentes methodes der stvrilisation du materiel chirurgical sont passes en revue. Les methodes discutees sont l'ebullition, I'air chaud, la vapeur sous pression, les produits chimiques et les rayons gamma. Zusammenfassung— Es wird ein Uberblick uber die Vor- und Nachteile der verschiedenen Methoden zur Sterilisierung aller in der Chirurgie verwendeten Gegenstande gegeben. Folgende Methoden werden besprochen: Kochen, die Verwendung von Heissluft, von unter Druck stehendem Dampf, von aktischen Strahlen und Gammastrahlen.

An account is given of the use to which bone autografts may be put in the repair of non-union fractures and in the treatment of severe carpal injuries in dogs. The methods of obtaining grafts of rib, iliac crest and tibial cortex are described, as are also the techniques for their employment at fracture sites and for carpal fusion. Four case protocols are provided for each category of procedure. Important theoretical considerations are discussed regarding the fate of grafted bone, the value of a bone bank and the use of bone homografts and bone heterografts. Resume. L'auteur donne un apercu des possibilites de recours aux autogreffes osseuses pour la reparation des fractures avec desunion et dans le traitement des lesions carpiennes graves chez le chien. II de'crit les methodes d'obtention de greffons des cotes, de la crete iliaque et du cortex tibial, ainsi que les techniques de mise en place au site des fractures et en vue du fusionne-ment carpien. Chaque precede est illustre par quatre comptes rendus de cas. Le sort des os greffes l'importance d'une banque des os et l'emploi d'homogreffes et d'heterogreffes font l'objet d'importantes considerations theoriques. Zusammenfassung. Es wird ein Bericht uber die Anwendung von Knochenautoplastik bei der Behandlung nichtheilender Frakturen und schwerer Carpaliaverletzungen bei Hunden gegben. Die Methoden zur Gewinnung von Pfropfungsmaterial von Rippen, Huftbeinkamm und Tibialcortex werden beschrieben, ebenso die Methoden der Verwendung an Bruchstellen und zur Heilung von Carpaliaverletzungen. Fur jede Art des Verfahrens werden vier Fallproto-kolle wiedergegeben. Wichtige theoretische Uberlegungen hinsichtlich des Schicksals gepfropfter Knochensubstanz, des Wertes einer Knochenbank und der Verwendung von Homoio- und Heteroknochenpfropfungen werden besprochen.

— A checklist is given of equipment required for orthopaedic surgery in small animals. The items are listed under instruments and implants, including care and selection of size of implants (screws, plates and medullary pins). Resume— Une Iiste est fournie du materiel necessaire en chirurgie orthopedique chez l'animal de petite taille. Les articles sont classes sous les rubriques instruments et pieces d'implantation, com-prenant des indications quant au maintien et au choix de ces dernieres (vis, plaques et clous medul-laires). Zusammenfassung— Es wird eine Prufliste der fur die Orthopadie kleiner Tiere notwendigen Gerate gegeben. Die Einzelgegenstande werden unter den Sammelbegriffen Instrumente und Implanate aufgezahlt. Letztere Gruppe umfasst auch die sorgfaltige Auswahl der Grosse der Im-planate (Schrauben, Platten und Medullarstifte).

A survey of cadaver material was undertaken in order to determine the prevalence of arthritis of the canine stifle joint. One hundred and fifty unselected cadavers were obtained from veterinary practices for this purpose, and their stifle joints were radiographed and dissected to discover abnormalities. Thirty-one dogs (20 per cent) had stifle arthritis and in all except one the lesions were characteristic of osteoarthritis. In the exceptional case infection was the cause. A mechanical derangement was present in 20 of the 54 affected joints, in the form of rupture of the anterior cruciate ligament (10), meniscal tears (9) and patellar dislocation (1). The cause of the arthritis in the other 33 joints is unknown.

Contrast radiography, using a 25 per cent solution of sodium diatrizoate, has been used for the investigation of tenosynovitis and bursitis in horses. The procedure was undertaken on a series of 32 clinical cases and on specimens obtained at autopsy. Lesions affecting the extensor tendon sheaths at the carpus, the digital sheath, the tarsal sheath and the bursae at the elbow, hock and fetlock were examined by this means. The results showed the procedure offered the clinician useful information about the nature of the interior of these structures, particularly as regards the presence of adhesions and anastomoses between adjacent sheaths and joint capsules. Together with other clinical and laboratory findings, contrast radiography can assist in assessing the prognosis and in formulating appropriate treatment.

Among 92 dogs with disturbance of a growth plate, were 58 with early closure of the distal ulnar pla'te. For the latter group the breed, sex and age prevalence are indicated, and an account is provided of the main clinical and radiographic features associated with this condition. Treatment was by stapling in the majority while others were treated by osteotomy or conservatively. Measurements were made on radiographs of the bones affected to establish the degree of length loss before and after treatment. Aspects of the aetiology, diagnosis and treatment of this condition are discussed.

Summary Contrast radiography was used to determine the position, shape, relationship and capacity of a number of tendon sheaths and bursae which have clinical significance in the horse. It was possible to establish the normal range of radiographic anatomy for these structures. Some variation in the extent and form of tendon sheaths were found between individual horses and between foals and adults.

Surgical deepening of the groove in the femoral trochlea is a technique commonly employed in the correction of patellar dislocation in dogs. In order to discover how this deep articular defect repairs the operation was studied experimentally in young goats. Observations were made on the appearance of the trochlea and the histologic changes that had taken place after approximately six, 12, and 40 weeks. The abraded groove became filled with fibrocartilage with a relatively smooth surface and it articulated freely with the patella. The majority of the replacement tissues arose by differentiation of the granulation tissue which initially filled the groove, but there appeared to have been some contribution made by the hyaline cartilage at the margins of the groove.

The authors describe certain muscle relocation techniques for the treatment of peripheral nerve injuries (radial and peroneal) in small animals. Six clinical cases are related illustrating the usefulness of the techniques. It is stressed that only a functional muscle can be relocated and that the majority of peripheral nerve lesions in the dog and cat are too extensive, involving a number of nerves, to allow the application of such techniques. However, the procedures can be of great value in certain selected cases, avoiding limb amputation or euthanasia of the patient.

This paper describes the histopathology of chronic tuberculin-type hypersensitivity reactions in the normal canine and malignant human prostate. Seven dogs were sensitized by injection of Freund's complete adjuvant and the histological response to the subsequent intra-prostatic injection of 6 mg tuberculin PPD was documented. A chronic mononuclear cell prostatis persisted for 4 weeks and was accompanied by paracortical distension and follicular hyperplasia in regional lymph nodes. Six patients with carcinoma of the prostate were given multiple intraprostatic injections of BCG, which induced a chronic mononuclear cell prostatitis with some evidence of tumour-cell necrosis. The study indicated that the prostate can support chronic cell-mediated allergic reactions to extrinsic antigens and that intra-prostatic injections of BCG can be administered without harmful effects to patients with malignant prostatic disease.

— —Osteochondritis dissecans of the humeral head has been observed in twenty-two dogs. It affected eleven different breeds but was most common in the Pyrehean and Labrador. The dogs at the onset of the lameness varied in age from 1 to 8 months; eighteen were males. A particular study was made of the radiologic changes that occurred in affected joints over a period of many months. Of the eighteen unilateral cases, the majority recovered soundness in 9–12 months bur lameness has persisted in all four dogs which were bilaterally affected. Intra-articular injections of a corticosteroid proved the most effective way of alleviating the symptoms. The breed distribution, age and sex incidence, radiologic features, etiology and treatment of the condition are discussed. Resume— —L'auteur a etudie vingt-dew chiens atteints d'osteochondrite (osteochondritis dissecans) de la tete de I'humerus. Les sujets etudies representaient onze races differentes, l'affection en cause etant particulitrement frequente chez les chiens de montagne des Pyrenees et les chiens du Labrador. L'âge des chiens au moment de la premitre attaque se situait entre 1 et 8 mois; le groupe etudie comprenait dix-huit chiens mâles. L'auteur a notamment poursuivi pendant de nombreux mois l'etude radiologique des alterations des articulations atteintes. La rnajorite des dix-huit chiens presentant une affection unilaterale ont ete retablis en 9 a 12 mois, tandis que les boiteries ont persiste dam les quatre cas d'osteochondrite bilaterale. L'injection intra-articulaire d'un corticosteroide s'est averee constituer le plus efficace traitement symptomatique. L'auteur examine le probleme sous ses divers aspects: frequence de l'affection suivant la race, l'âge et le sexe des sujets, caracteriques radiologiques, etiologie et traitement. Zusammenfassung— —Osteochondritis dissecans des Hurneruskopfes wurde bei zweiundzwanzig Hunden beobachtet. Der Zustand trat bei elf verschiedenen Rassen ad, war aber am haufigsten beim Pyrenaenhund und beim Labradorhund. Beim Eintritt der Lahmheit waren die Hunde 1–8 Monate alt, und achtzehn Tiere waren Ruden. Besonders untersucht wurden die radiologischen Veranderungen, die wahrend einer Periode von vielen Monaten an den befallenen Gelenken auftraten. Von den achtzehn einseitigen Fallen gesundete die Mehrzahl in 9–12 Monaten, aber die Lahmheit hielt bei allen vier Hunden an, die beidseitig befallen waren. Intraartikulare Injektionen eines Corticosteroids erwiesen sich als das wirksamste Mittel zur Behandlung der Symptome. Die Verteilung auf Rassen, Haufigkeit nach Alter und Geschlecht, radiologischen Befunde, Atiologie und Behandlung des Zustands werden besprochen.

Osteoarthritis of the shoulder was discovered in twelve canine cadavers during an extensive survey that was primarily conducted to study stifle arthritis. Clinical, radiographic and pathological aspects of the shoulder arthropathies are described. The significance of these lesions in the aetiology of shoulder lameness and difficulties associated with their diagnosis are discussed. Resume. On a observe une osteoarthrite de l'epaule chex douze cadavres canins pendant une etude poussee qui etait en principe menee pur etudier l'arthrite du grasset. On decrit les aspects cliniques, radiographiques et pathologiques de l'arthropathie de l'epaule. On discute de la signification de ces lesions dans l'aetiologie du rhumatisme de l'epaule et des difficultes associees avec leur diagnostic. Zusammenfassung. Osteoarthritis der Schulter fand man in zwolf Hundekadavern wahrend eines umfassenden uberlicks der hauptsachlich ausgefuhrt wurde, um Kniescheibenarthritis zu studieren. Klinische, radiographische und pathologische Ansichten uber Schulter-Arthrosis-deformans sing beschrieben. Die Bedeutung dieser Lasionen in der atiologie von Schulterlahmheit und Schwierigkeiten, die mit ihrer Diagnose verbun den sind, werden diskutiert.