D. Van Vynckt

Primary flexor enthesopathy of the canine elbow: imaging and arthroscopic findings in eight dogs with discrete radiographic changes

OBJECTIVE To describe the radiographic, ultrasonographic, computed tomography (CT), magnetic resonance imaging (MRI), and arthroscopic findings in eight dogs with elbow lameness caused by primary flexor enthesopathy. STUDY DESIGN Clinical study. ANIMALS Eight client-owned dogs. METHODS In all dogs, lameness was localized to the elbow by clinical examination. Radiographic examination, ultrasound, CT and MRI were performed prior to arthroscopy. In seven dogs, surgical treatment and subsequent histopathology were performed. RESULTS Primary enthesopathy of the medial epicondyle was diagnosed in eight dogs (13 joints) by combining the minimal radiographic changes with specific ultrasonographic, CT, MRI and arthroscopic findings at the medial epicondyle. In all joints, any other pathology could be excluded. Histopathology of the affected tissue revealed degeneration and metaplasia in the flexor muscles. CONCLUSIONS Primary flexor enthesopathy at the medial epicondyle is an unrecognized condition and is a possible cause of elbow lameness in the dog. Diagnosis is based on specific imaging and arthroscopic findings. CLINICAL RELEVANCE The most important cause of elbow lameness in dogs is medial coronoid disease. Often this condition presents with minimal radiographic and arthroscopic changes. In these cases, primary enthesopathy of the medial epicondyle should be considered as a differential diagnosis, in order to make the correct treatment decision.

A review of the human and veterinary literature on local anaesthetics and their intra-articular use. Relevant information for lameness diagnosis in the dog.

Lameness in dogs is often a diagnostic challenge. In many cases it is difficult to determine the exact localisation of lameness because of the absence of palpable changes, or because of unreliable pain response due to high pain tolerance, stress or aggression of the dog. In horses and humans, intra-articular administration of local anaesthetics is commonly used for diagnostic purposes. In this review, information from human and veterinary studies on different local anaesthetic agents and their application for diagnostic intra-articular anaesthesia is given. Based on this information, a protocol for diagnostic intra-articular anaesthesia in the dog can be developed and evaluated in future studies.

Erosion of the medial compartment of the canine elbow: occurrence, diagnosis and currently available treatment options

Erosion of the medial compartment of the elbow joint refers to full thickness cartilage loss with exposure of the subchondral bone (modified Outerbridge grades 4-5) of the medial part of the humeral condyle (MHC) and the corresponding ulnar contact area. This finding may appear in the absence of an osteochondral fragment or a cartilage flap, or in combination with fragmentation of the medial coronoid process (MCP) or osteochondritis dissecans (OCD) of the MHC. With regard to the prognosis, it is important to diagnose these severe erosions. Imaging of cartilage lesions by means of radiography, ultrasonography, computed tomography or magnetic resonance imaging is challenging in dogs. In contrast, direct arthroscopic inspection provides detailed information about the cartilage. The treatment of these severe erosions is difficult because of the limited regenerative capacity of cartilage and presumed mechanical or physical triggering factors. Several conservative and surgical treatment methods have been proposed to treat elbows with severe cartilage defects. However, due to irreversible loss of cartilage, the prognosis in these cases remains guarded.

Arthroscopic treatment of fragmented coronoid process with severe elbow incongruity. Long-term follow-up in eight Bernese Mountain Dogs.

The purpose of this study was to investigate the long-term treatment results of fragmented coronoid process (FCP) in joints with a radio-ulnar step greater than 3 mm. Treatment of these patients only consisted of fragment removal, without correction of the incongruity. The eight Bernese Mountain Dogs (11 joints) included in this study showed obvious clinical signs of elbow disease and were diagnosed with severe elbow incongruity and concomitant FCP in the time period from 1999-2003. At that time, elbow radiography, computed tomography, and arthroscopy were performed. The mean follow-up period was 5.6 years. The follow-up consisted of a telephone questionnaire combined with a clinical and radiographic re-evaluation at our clinic. The questionnaire revealed that all dogs were either free of lameness or only lame following heavy exercise. One dog sporadically required medication after heavy exercise. The owner satisfaction rate was 100%. The clinical re-evaluation did not reveal any signs of pain or lameness in all cases. Range-of- motion was decreased in nine of the 11 elbows. Radiographs revealed an increase in severity of osteoarthritis in every case.In this case series, arthroscopic fragment removal without treatment of incongruity was demonstrated to be a valuable treatment option and may provide a satisfactory long-term outcome.

Single-phase bone scintigraphy in dogs with obscure lameness

OBJECTIVES To evaluate the diagnostic merits of scintigraphy in dogs with clinically obscure lameness origin. METHODS In 43 dogs, the scintigraphic findings were compared with the results of subsequent radiological, computed tomography and/or arthroscopic findings and/or additional neurological examination. RESULTS In all dogs, focal increased uptake was found in one or more joints or bones. The presence of associated pathology was confirmed by radiography, computed tomography and/or arthroscopy of the limb region of interest. Additional neurological examination was performed when indicated. In cases of elbow pathology, unilateral involvement of the elbow was confirmed with computed tomography/arthroscopy in 14 cases, while bilateral increased uptake could not be confirmed with radiography or computed tomography in three cases. Three dogs showed an increased activity in one joint on the bone scan, while computed tomography, arthroscopy or radiography revealed bilateral joint disease. Generalised mild increased radionuclide uptake in all joints and bones was observed in the lame limb in 15 forelimbs and five hindlimbs. Generalised prominent uptake of an entire limb was noted in three cases suffering from neurological disease. CLINICAL SIGNIFICANCE Scintigraphy may provide information on areas of increased radionuclide uptake, thereby aiding in the localisation of obscure lameness. Generalised mild increased uptake of radionuclide in all joints and bones in the lame limb may occur in the older dog. The generalised prominent uptake, seen in three cases with neurological disease, may resemble reflex sympathetic dystrophy syndrome seen in human beings.

Diagnostic intra-articular anaesthesia of the elbow in dogs with medial coronoid disease

OBJECTIVE Assessment of the effect of intra-articular anaesthesia on lameness caused by medial coronoid disease. METHODS This study included 90 dogs that were evaluated for the complaint of unilateral forelimb lameness. All dogs were suspected of having an elbow problem for which orthopaedic examination and radiographs showed inconclusive findings. Following a short sedation, mepivacaine was injected intra-articularly to determine whether lameness was caused by a suspected elbow problem. This effect was compared with the final diagnosis based on computed tomography and arthroscopy. RESULTS Out of 90 dogs, 78 (87%) dogs had an improvement of lameness after injection of the local anaesthetic, which confirmed the elbow joint as the primary source of lameness. A positive response was seen in all types of medial coronoid lesions. A false negative result was observed in 12 dogs (13%). CLINICAL RELEVANCE Medial coronoid disease is represented by different types of pathologic lesions including chondromalacia, fissures, fragments, and medial compartment disease. Diagnosis may be difficult because of limited clinical or radiographic signs or a combination of both. Intra-articular anaesthesia can be a helpful diagnostic tool to localize the problem by eliminating pain and reducing lameness to a great extent in all types of coronoid lesions.

Evaluation of two sedation protocols for use before diagnostic intra-articular anaesthesia in lame dogs

OBJECTIVES To assess the influence of two sedation protocols on the degree of lameness in dogs. METHODS Fifty lame dogs were allocated to one of two sedation protocols. Group ACPM (acepromazine + methadone; n=25) was sedated with acepromazine and methadone. Group MED (medetomidine antagonised with atipamezole; n=25) was sedated with medetomidine and reversed with atipamezole. Each dog was evaluated for lameness before and after sedation using videotapes. Four experienced clinicians allocated global lameness scores before and after sedation to each dog using a numerical rating scale. RESULTS In 80% of the dogs in group ACPM and in 72% in group MED lameness was not affected by the sedation. In 12% of the dogs in group ACPM and 20% of the dogs in group MED the observers noticed an increase of lameness of 1 or 2 degrees on a scale of 0 to 10. In 8% of the dogs in both groups lameness decreased with 1 degree. CLINICAL RELEVANCE A possible diagnostic test for investigation of obscure lameness is intra-articular anaesthesia. Sedation is necessary to allow intra-articular injection. This study provided evidence that the effect of sedation with the proposed protocols on the degree of lameness is negligible.

Osteochondritis dissecans of the humeral head in two small-breed dogs

Shoulder pathology consistent with osteochondritis dissecans of the humeral head was diagnosed in two small-breed dogs. In both cases, the diagnosis was made tentatively on the basis of radiography and confirmed by arthroscopy of the affected shoulder joint. Both dogs were successfully treated by surgical removal of a flap of cartilage from the affected area. Clinical and radiographic follow-up was available in both cases. The excised cartilage flaps were examined histopathologically and showed the same characteristics as cartilage flaps from dogs of large breeds prone to developing osteochondritis dissecans of the shoulder.