Surgical resection of an osteoma of two thoracic spinous processes in a horse

This report describes the successful surgical removal of an osteoma of the thoracic dorsal spinous processes of a horse that presented with back pain. Osteomas of the spine are frequently reported in the literature in people, but have not been previously described in the horse.     

Close, impinging and overriding spinous processes in the thoracolumbar spine: the relationship between radiological and scintigraphic findings and clinical signs

Reasons for performing study: There has been no objective study comparing radiological features of spinous processes (SPs) in the thoracolumbar region and/or scintigraphic findings with clinical signs. Objectives: To investigate the relationship between the presence or absence of clinical signs of back pain and: 1) radiological findings of close, impinging or overriding SPs; 2) increased radiopharmaceutical uptake (IRU) in the SPs; and 3) the combination of radiological findings and IRU. Also to determine the prevalence of concurrent osseous pathology. Methods: Five‐hundred and eighty‐two horses, presented for perceived back pain and poor performance, underwent comprehensive clinical investigation including diagnostic analgesia of the forelimbs, hindlimbs, back and sacroiliac joints, and radiographic and scintigraphic evaluation of the thoracolumbar spine. Radiological and scintigraphic grades were determined subjectively. Statistical analysis was performed to determine the relationships between clinical signs of back pain, radiological and scintigraphic features, age, breed, gender, discipline, height and weight. Results: Thoroughbreds (TBs) were over‐represented with thoracolumbar pain compared with Warmbloods and TB cross breeds. There was a significant association between maximum and total radiological grades of the SPs and thoracolumbar pain, between maximum and total grades of IRU and thoracolumbar pain, and between a combination of radiological and scintigraphic abnormalities and thoracolumbar pain. Horses with osteoarthritis (OA) of the synovial intervertebral articulations (SIAs) were more likely to have thoracolumbar pain than horses with lesions of the SPs alone, but the presence of OA of the SIAs and lesions of the SPs was associated with the highest likelihood of thoracolumbar pain. Conclusions and potential relevance: Fore‐ or hindlimb lameness and/or pain associated with the sacroiliac joints could mimic primary thoracolumbar pain. A combination of radiology and scintigraphy gives the most accurate prediction of thoracolumbar pain, but diagnostic analgesia is crucial for accurate diagnosis.     

Palmar process fractures of the distal phalanx in foals: A review

Distal phalanx fractures are well documented in adult horses, but our knowledge of such fractures in foals is limited. Recent studies showed a high incidence of distal phalanx palmar process (PP) fractures in foals, the aetiology is not yet known. Several hypotheses have been suggested as possible causes, including uneven compressive forces, unequal forces from the deep digital flexor tendon, composition and shape of the PP, and conformation. A better understanding of the aetiology and predisposing factors requires further research. Radiography is the commonly used imaging modality for diagnosis of such fractures; however, those fractures might be missed on routine radiographic projections. In order to have a high probability of identifying fractures, a series of 5 radiographs including the oblique views is required. This article reviews the incidence of distal phalanx PP fractures and discusses the diagnosis of such fractures.     

Subtotal ostectomy of dorsal spinous processes performed in nine standing horses

OBJECTIVE: To describe and evaluate subtotal ostectomy of dorsal spinous processes (DSP) performed in standing horses. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Nine adult horses. METHODS: The diseased portions of the DSP were removed with the horses standing and sedated after infiltrating a local anesthetic agent around the affected DSP. Medical records of affected horses were reviewed to determine history, findings of physical and radiographic examination, surgical technique, postoperative complications, and outcome. RESULTS: Five horses had subtotal ostectomy of DSP because of osteomyelitis, and 4 because of impingement and/or fracture of DSP. Affected portions of DSP were removed safely and effectively, with no apparent discomfort to the horses; hemorrhage was minimal. CONCLUSIONS: Subtotal ostectomy of DSP can be performed safely in standing, conscious horses and the risks associated with general anesthesia are eliminated. Hemorrhage is minimal compared to that which occurs when the procedure is performed with horses anesthetized and in lateral recumbency. CLINICAL RELEVANCE: Access and visibility are better when subtotal ostectomy of the DSP is performed with the horse standing rather than anesthetized and in lateral recumbency. Performing subtotal ostectomy of diseased DSP with the horse standing avoids the expense and risks of general anesthesia.     

Thoracic processi spinosi findings agree among subjective,semiquantitative, and modified semiquantitative scintigraphic image evaluation methods and partially agree with clinical findings in horses with and without thoracolumbar pain

Impinging processi spinosi in the equine thoracic spine are a common cause of poor performance in the horse. A modified semiquantitative scintigraphic image analysis has been proposed for the evaluation of equine processi spinosi. This technique showed a high inter‐ and intraobserver agreement when compared to subjective and semiquantitative image analysis. The aim of this retrospective, method comparison study was to evaluate the agreement of the modified semiquantitative scintigraphic image assessment with previous methods of interpretation and to compare these scintigraphic evaluation techniques with radiographic and clinical findings. Two hundred twenty‐three Warmblood horses that underwent scintigraphic, radiographic, and clinical examination of the thoracic spine were included in the study. Scintigraphic images were assessed using subjective, semiquantitative, and modified semiquantitative techniques. Radiographs were subjectively graded and horses were assigned to a group with or without thoracolumbar pain. Total radiographic and total scintigraphic grades were higher in horses with thoracolumbar pain (P < 0.05). Both the semiquantitative and the modified semiquantitative uptake ratios did not differ significantly in horses with or without thoracolumbar pain. The kappa agreement showed a substantial agreement between the modified semiquantitative scintigraphic and the semiquantitative scintigraphic evaluation techniques. The agreement between subjective scintigraphic and modified semiquantitative scintigraphic image evaluations was fair. There was a slight agreement between all scintigraphic techniques and radiographic findings. Limitations were the definition of thoracolumbar pain and the image analysis being restricted to the caudal thoracic processi spinosi. In conclusion, the modified semiquantitative scintigraphic image assessment obtained consistent results but did not perform better than previous evaluation methods. Further comparison to a defined diagnosis is warranted.     

Haematogenous septic arthritis,physitis and osteomyelitis in foals: A tutorial review on pathogenesis,diagnosis, treatment and prognosis. Part 1

Haematogenous septic arthritis, physitis and osteomyelitis (SAPO) is a potentially debilitating or even life-threatening disease entity encountered in foals of all ages between birth and approximately 7 months old. Correct, and complete, diagnosis and successful treatment require collaboration between specialties including medicine, anaesthesia, diagnostic imaging, surgery and rehabilitation services. However, in order to succeed, it is important that all specialties have an overall knowledge of all aspects of the disease complex. Therefore, the aim of this review is to give an overview of aetiology, presenting complaints, clinical findings, diagnostic imaging, treatment, rehabilitation and prognosis. Part one deals with all aspects of aetiology and how to make a diagnosis. Part two deals with all aspects of treatment, rehabilitation and prognosis.     

Congenital hypothyroidism and dysmaturity syndrome in foals: First reported cases in Europe

Congenital hypothyroidism and dysmaturity syndrome (CHD) in neonatal foals was first described in western Canada in 1981 and remains an important problem for the western Canadian horse industry. This syndrome is characterised by hyperplasia of the thyroid gland, increased gestational length and multiple congenital musculoskeletal abnormalities. This case series describes the first confirmed cases of CHD in Europe and challenges contemporary opinion which suggests that this syndrome is distinct from congenital hypothyroidism associated with visible goitre.     

Diagnostic utility of computed tomography imaging in foals: 10 cases (2008–2010)

Despite an increasing number of case reports published using computed tomography (CT) in foals only limited data on its diagnostic utility are available. Medical and imaging records of 10 foals that had a CT examination between May 2008 and December 2010 were retrieved and studied. Three out of 10 cases were examined for orthopaedic problems, 3 were referred for medical disorders, 3 for both orthopaedic and medical problems, and one case was presented for a follow‐up of an abdominal mass. In this series CT was an accurate diagnostic tool in identifying abscesses, osteomyelitis, arthritis, physitis and fractures, bone ossification defects, intracranial haematomas and sinusitis. An indication for the best medical and/or surgical approach was obtained.     

Management and assessment of prognosis after gastrocnemius disruption in Thoroughbred foals: 28 cases (1993–2007)

Reasons for performing study: Few studies have evaluated the athletic prognosis of foals affected by gastrocnemius disruption. Objective: To examine the diagnosis and management of gastrocnemius disruption in Thoroughbred (TB) foals, determine short‐term survival rate and assess future racing performance. The hypothesis was that Thoroughbred foals with gastrocnemius disruption are able to perform as racehorses comparably to their age matched maternal siblings. Methods: The medical records of foals diagnosed with gastrocnemius muscle disruption were reviewed. Information on training and racing was acquired from published works and race records. Paired t tests were utilised to compare performance variables of affected racehorses to their maternal siblings in starts, earnings and earnings/start for their 2‐ and 3‐year‐old racing seasons. Fisher's exact tests were employed to determine the association between sex, limb affected, age on admission, degree of caudal reciprocal apparatus dysfunction, concurrent disease, antibiotic therapy, complications, abscess formation and likelihood of entering training or starting a race. Results: Sample size was too small to detect significant differences in performance variables between affected horses and controls. Of 28 foals, 17 (61%) presented with concomitant illness; foals without concurrent disease were more likely to achieve race training or start a race (P = 0.04); 23 (82%) were short‐term survivors defined as survival to discharge. Of these 23 survivors, 7 were aged <2 years at the time of the study. Eighty‐one percent (13/16) of the survivors that were of racing age were in training or had started a race. Conclusions: In this population, 82% of TB foals affected with gastrocnemius disruption were able to achieve training or start a race. Foals presenting for gastrocnemius disruption have a high prevalence of concurrent disease processes. Potential relevance: The assessment of athletic prognosis and treatment complications provides useful information to clinicians treating gastrocnemius muscle disruption in foals and making recommendations to clientele.     

Development of osteochondrosis in Lusitano foals: A radiographic study

This study aimed to detect, by radiographic examination, the evolution of osteochondral lesions in the tarsocrural and femoropatellar joints of Lusitano foals. Within 1 month of age, 76.08% of foals had radiographic signs of osteochondrosis, but only 16.20% had lesions at 18 months. The radiographic signs resolved by 5 mo of age in most foals, but some cases that involved either joint, were not resolved until 12 mo of age. It is thought that the “age of no return” is 5 mo for the tarsocrural and 8 mo for the femoropatellar joint but this study demonstrated regression of osteochondral lesions in both joints of Lusitano foals up to 12 months of age.     

Prevalence of various radiographic manifestations of osteochondrosis and their correlations between and within joints in Dutch Warmblood horses

Reasons for performing study: Osteochondrosis (OC) is the most important orthopaedic developmental disorder in horses and may manifest in several different forms. No detailed study on the prevalence and/or interrelation of these forms is available, even though these data are a prerequisite for conclusive genetic studies. Objectives: To assess the prevalence of the various manifestations of OC as detected radiographically and to evaluate possible relationships between their occurrence within the same joint and between different joints. Methods: The FP (femoropatellar), TC (tarsocrural) and MCP/MTP (metacarpophalangeal/metatarsophalangeal) joints of 811 yearlings selected randomly, descending from 32 representative stallions, were radiographed and scored for the presence and grade of osteochondrotic lesions. Results were compared at the sire, animal, joint and predilection site levels. Results: In the FP joint, the percentage of animals showing normal joint contours in all sites was 60.7%. For the TC joint and the combined MCP/MTP joints, these figures were 68.6 and 64.6%, respectively. For all joints combined, the percentage dropped to 30.5%. Sedation improved detection of OC lesions in the FP joint. There was a high correlation between the right and left joints. The correlation between flattened bone contours and fragments was considerably less. Conclusions: Scoring on a detailed scale is necessary to achieve good insight into the prevalence of OC. Observations on the right and left joints can be combined in further analyses, whereas flattened bone contours and fragments should be evaluated as statistically different disorders. Potential relevance: This study provides insight into the prevalences of various manifestations of OC and their relationships, within and between joints. These results form the basis for detailed quantitative and/or molecular genetic studies that should lead to the establishment of breeding indices and/or genetic marker sets for OC.