The surgical treatment of osteochondritis dissecans of the humeral head in dogs

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.
Résumé. Les auteurs rapportent leurs expériences concernant le traitemerit chirurgical de 21 cas unilatéraux et de 13 cas bilatéraux d'ostéochondrite dissécante de l'humérus du chien. On décrit les techniques opératoires et les données de l'examen clinique. Dans presque tous les cas, on a obtenu une restauration presque complète de la fonction du membre dans les 3 mois qui ont suivi l'opération, ce qui représente un résultat nettement supérieur à celui obtenu dans des séries précédentes traitées par un mode conservateur. Dix-neuf des chiens atteints ont présenté des signes de dysplasie de la hanche.
Zusammenfassung. Die Autoren geben ihre Erfahrungen mit der chirurgischen Behandlung von 21 einseitigen und 13 beidseitigen Fällen von Osteochondritis dissecans des Humerus des Hundes bekannt. Die Operationstechnik und die klinische Pathologie des Zustands werden beschrieben. In fast allen Fällen wurde die vollständige Wiederherstellung der Extremitätenfunktion innerhalb von drei Monaten nach dem chirurgischen Eingriff erreicht; dies ist ein viel besseres Ergebnis, als mit einer früheren Reihe von Fällen durch konservative Behandlung erzielt wurde. Neunzehn der erkrankten Hunde wiesen Anzeichen von Hüftdysplasie auf.     

Biochemical characterization of cartilage affected by osteochondritis dissecans in the humeral head of dogs

OBJECTIVE: To determine glycosaminoglycan (GAG) concentration and immunohistochemical staining characteristics of type-I, -II, and -X collagen from cartilage affected by osteochondritis dissecans (OCD) in dogs. ANIMALS: 31 dogs with OCD and 11 clinically normal purpose-bred dogs. PROCEDURE: Cartilage samples were evaluated microscopically, and GAG content was determined. Immunohistochemical staining was performed for type-I, -II, and -X collagen. Sections were subjectively evaluated for location and intensity of staining. RESULTS: Cartilage affected by OCD had a variety of pathologic changes and significantly lower GAG concentrations than did normal cartilage. Normal cartilage had no detectable type-I collagen. For dogs < 9 months of age, cartilage affected by OCD had significantly more type-I collagen but significantly less type-X collagen than did control cartilage. For dogs > 12 months of age, cartilage affected by OCD contained significantly more type-I collagen than did control cartilage. There was a significant negative correlation between immunoreactivity of type-I collagen and that of type-II and -X collagen. A significant positive correlation was found between immunoreactivity of type-II and -X collagen. CONCLUSIONS AND CLINICAL RELEVANCE: Cartilage affected by OCD contains less GAG, more type-I collagen, and less type-X collagen, compared with normal cartilage. A direct correlation between these changes and the etiopathogenesis of OCD was not established.     

Osteochondral autograft transfer for treatment of osteochondritis dissecans of the caudocentral humeral head in dogs

Objective: To establish whether osteochondral autograft transfer (OAT) procedures for osteochondritis dissecans (OCD) of the canine caudocentral humeral head would restore articular contour, resurface osteochondral defects, and resolve lameness in dogs with OCD. Study Design: Case series. Animals: Dogs (n=14) with caudocentral humeral head OCD (16 shoulders). Methods: After arthroscopic assessment, the humeral head was exposed by arthrotomy. The OCD lesion was debrided and OATS^? instrumentation used for resurfacing the defect with osteochondral core grafts collected from the stifle. Recipient sockets were created to maximally resurface articular lesions. Outcomes measures included clinical, radiographic, and arthroscopic examination at 12–18 weeks and clinical examination at 12–46 months (mean, 30.8 months) postoperatively. Results: Resurfacing of the humeral head was achieved in all dogs. Subjectively, lameness resolved in 9 of 16 limbs by 5–6 weeks postoperatively, and in 13 limbs by 12–18 weeks. Radiographically, all autografts were maintained. On second‐look arthroscopy, the grafted section was intact, resilient on probing, satisfactorily conformed to the adjacent articular contour, and grossly appeared consistent with hyaline or fibrocartilage depending on the graft source. Of 12 limbs available for 12–46 months reevaluation, none were considered lame and mild discomfort on shoulder manipulation was recorded for only 1 joint. Conclusions: OAT procedures are technically feasible in the caudocentral aspect of the canine humeral head. Articular contour reconstruction, resurfacing of osteochondral defects, and amelioration or resolution of short‐term lameness may be achieved.     

Osteochondritis dissecans of the humeral head of a cat

A one-year-neutered male cat was presented for veterinary examination because of a left forlimb lameness. A painful left shoulder joint was found on examination and radiology of this joint revealed an erosive lesion of the humeral head and a detached flap of articular cartilage. The detached cartilage was surgically removed after which the lameness resolved. The lesion in this cat resembled osteochondritis dessicans of other species but whether the pathogenesis of the condition in this cat was 115 similar also was not determined.     

A study of osteochondritis dissecans of the canine humeral head using histological, OTC bone labelling, microradiographic and microangiographic methods

A total of forty-three cases of osteochondritis dissecans were encountered in fourteen breeds. Five of them were used for histological study. Changes were revealed in nine humeral heads: in two of an early stage, in four of an advanced stage and in three of a late stage. In the early stage, the germinative zone of the articular cartilage displayed an irregular arrangement of cells lacking nuclei and an intracartilaginous cleavage with bridge formations. There were new bone formations and thick bone trabeculae subchondrally. In the advanced stage a loose fragment of articular cartilage or ossified cartilage was found. Remodelling of the bone extended to the epiphyseal cartilage which displayed scattered architecture. In the late stage more granulation tissue, ossifying cartilage and new bone formation extended to the cleft in the area of bone remodelling. Osteophytelike formations were found. The importance of degenerative changes of the articular cartilage and the intracartilaginous cleavage as the initial stage in the development of osteochondritis dissecans was discussed. Résumé. On a rencontré quarante-trois cas d'ostéochondrite disséquante dans quatorze races, dont cinq furent soumises à une étude histologique. On a observé des changements de neuf têtes humérales: deux à un stade précoce, quatre à un stade avancé et trois à un stade tardif. Au stade précoce, la zone germinative du cartilage articulaire révélait une formation irrégulière de cellules ayant sans noyau et une segmentation intercartilagineuse avec formation de ponts. On a observé une nouvelle formation des os et que les trabécules des os etaient épais en-dessous du cartilage. Au stade avancé, on a trouvé un fragment détaché de cartilage articulaire ou de cartilage ossifié. Cette transformation de l'os allait jusqu'au cartilage épiphysaire, qui avait une configuration dispersée. Au stade tardif, on a assisté à une plus forte granulation des tissus, à une ossification du cartilage et à une nouvelle formation de l'os qui menaient à une scissure au point de transformation de l'os. On a rencontré des formations semblables aux ostéophytes. On passé en revue l'importance de ces changements dégénérescents du cartilage articulaire et de la segmentation intercartilagineuse en tant que stade initial conduisant à l'ostéochondrite disséquante. Zusammenfassung. Insgesamt 43 Fälle von Osteochondritis dissecans wurden bei 14 Rassen vorgefunden. Fünf davon wurden histologisch untersucht. Veränderungen wurden in neum Humerusköpfen festgestellt: bei zwei davon in einem Frühstadium, bei vier in einem fortgeschrittenen Stadium und bei drei in einem Spätstadium. Im Frühstadium zeigte die Germinatiuzone des articularen Knorpelgewebes eine unregelmässige Anordnung kernloser Zellen und eine innerc Knorpelgewebespaltung mit Brückenbildungen. Es lagen Knochenneubildung und subchondral dicke Knochentrabeculae vor. Im fortgeschrittenen Stadium wurde ein loses Fragment articularen Knorpelgewebes oder ossifizierten Knorpelgewebes gefunden. Knochenumbildung erstreckte sich bis zum epiphysealen Knorpelgewebe, welches eine verstreute Architektur zeigte. Im Spästadium erstreckten sich mehr Granulationsgewebe, ossifizierendes Knorpelgewebe und Knochenneubildung bis zu dem Spalt im Gebiet der Knochenumbildung. Osteophytenähnliche Bildungen wurden gefunden. Die Bedeutung der degenerativen Veränderungen irn articularen Knorpelgewebe und der im Knorpelgewebe auftretenden Spaltung als Einleitungsstadium in der Entwicklung von Osteochondritis dissecans wird besprochen.     

Bilateral stifle osteochondritis dissecans in a cat

A 9-month-old, castrated male, domestic shorthaired cat was presented for progressive right hind-limb lameness. A diagnosis of osteochondritis dissecans of the lateral femoral condyle was made based on radiographs and physical examination, and was confirmed by right lateral stifle arthrotomy. The cartilage flap was removed, and the underlying bone was curetted. Seven months later, the cat was sound on the right leg but developed a left hind-limb lameness. A similar lesion was found in the left leg and was treated identically. Fourteen months after presentation, the cat was sound on both hind limbs.     

Glenoid dysplasia and osteochondritis dissecans in a cat

A 2-year-old Maine coon cat was presented for a right forelimb lameness. Computed tomography of the shoulder revealed a shallow glenoid, osteophyte deposition at the caudal humeral head and medial glenoid, and an intra-articular osseous body. This cat had glenoid dysplasia and osteochondritis dissecans of the glenoid.     

Radiographic signs of osteochondritis dissecans of the lateral ridge of the trochlea tali in the dog

Osteochondritis dissecans lesions of the lateral ridge of the trochlea of the talus occur infrequently and are difficult to diagnose. They occur mainly in the proximal or proximodorsal section of the lateral ridge of the trochlea and are best seen in the plantaromedial-dorsolateral oblique projection (with the X-ray beam angled 30 to 45^o from the vertical), and in the fully flexed and extended mediolateral projections. The flexed dorsoplantar projection using a horizontal beam is also useful.     

Arthroscopic-assisted management of osteochondritis dissecans in the stifle of a cat

An 11-month-old, male neutered, domestic short-haired cat presented for evaluation of sudden onset right pelvic limb lameness. Radiography showed features consistent with unilateral osteochondritis dissecans (OCD) of the lateral femoral condyle in the right stifle. Arthroscopic examination of the stifle was used to confirm the presence of an articular cartilage lesion and the presence of loose cartilage within the joint. The loose cartilage fragments were removed arthroscopically. One arthroscopy portal was extended into a limited arthrotomy, which was necessary to ensure complete debridement of the defect. Removal of the fragments led to complete resolution of the clinical signs. This case report documents a more minimally invasive technique for the management of stifle OCD in the cat than previously documented and helps to establish a protocol for arthroscopic surgery in the feline stifle.     

A case of osteochondritis dissecans of the stifle joints in a bitch

A condition of the stifle joints of a young Alsatian bitch, resembling osteochondritis dissecans of the humeral head of the dog, is described. This case is compared with osteochondritis dissecans of the canine humeral head and with osteochondritis dissecans of the human knee.
Résumé. On décrit une atteinte du grasset d'une jeune chienne alsacienne ressemblant à l'ostéo-chondrite disséquante de la tête humérale du chien; on fait un parallèle entre la présente observation, et l'ostéochondrite disséquante de l'articulation du genou humain.
Zusammenfassung. Es wird ein Zustand der Kniegelenke einer jungen Schäferhündin beschrieben, die der Osteochondritis dissecans des Humeruskopfes beirn Hund gleicht. Dieser Fall wird mit Osteochondritis dissecans des Humeruskopfes des Hundes und mit Osteochondritis dissecans des menschlichen Knies verglichen.     

Osteosarcoma at the site of bone infarction associated with total hip arthroplasty in a dog

OBJECTIVE: To report the occurrence of medullary bone infarction in both femoral canals after bilateral total hip arthroplasty (THA) and the subsequent unilateral development of an osteosarcoma at the site of bone infarction. STUDY DESIGN: Clinical report. ANIMAL POPULATION: An 8-month-old neutered male Samoyed dog. METHODS: Serial physical and radiographic examinations performed at 1, 2, 3, and 5 years after THA. Bone biopsy specimens of the right distal femoral metaphysis were taken 5 years after THA, and a complete necropsy was performed at the time of euthanasia. RESULTS: Bilateral medullary bone infarction was visible in the femoral canals 1 year after THA and remained visible on subsequent evaluations. An osteosarcoma developed in the right distal femoral metaphysis at the site of infarction, 5 years after THA, and was found to have metastasized widely throughout the body. CONCLUSION: Bone infarction may occur in the femoral canal after canine THA. CLINICAL RELEVANCE: Bone infarction may be a predisposing factor for the development of osteosarcoma in the femora of dogs with THAs.     

Osteosarcoma of the patella in a dog

Osteosarcoma of the patella was diagnosed by biopsy in a 9-year-old, male dog of mixed breeding. The dog was originally examined because of intermittent lameness of the left hindlimb; there were minimal palpable abnormalities of the stifle. After the diagnosis, the owner refused further treatment for the dog. The dog was reexamined 13 months later because of a marked swelling of the stifle. The dog was euthanatized and necropsy findings confirmed the diagnosis.     

Involvement of trauma in the pathogenesis of osteochondritis dissecans in swine.

Limb joint soundness was examined in 40 pigs loaded into a wooden box cart and 40 control pigs not subjected to loading. On postmortem examination, eight loaded pigs showed osteochondritis dissecans in their medial humeral condyles, suggesting that porcine joints are vulnerable to osteochondral lesions when mechanically overloaded. Prevention of trauma by careful handling of pigs during penning and transportation should help to control joint lesions and lameness.     

Stifle osteochondritis dissecans in snow leopards (Uncia uncia)

Three snow leopard (Uncia uncia) cubs, female and male siblings and an unrelated female, had lameness attributed to osteochondritis dissecans (OCD) lesions noted at 6, 8, and 10 mo of age, respectively. All cubs were diagnosed with OCD via radiographs. The sibling cubs both had lesions of the right lateral femoral condyles, while the unrelated cub had bilateral lesions of the lateral femoral condyles. Subsequently, OCD was confirmed in all three cases during surgical correction of the lateral femoral condyle lesions via lateral stifle arthrotomies, flap removal, and debridement of the defect sites. Histopathology also supported the diagnosis of OCD. Postoperatively, the sibling cubs developed seromas at the incision sites and mild lameness, which resolved within a month. To date, two cubs have been orthopedically sound, while one of the sibling cubs has developed mild osteoarthritis. OCD has rarely been reported in domestic felids, and to the authors' knowledge these are the first reported cases of OCD in nondomestic felids.