Findings consistent with equine proximal suspensory desmitis can be reliably detected using computed tomography and differ between affected horses and controls.

The objective of this retrospective, observational, controlled study was to evaluate bone and soft tissue window CT images of the proximoplantar metatarsus III region in twenty horses with pain localized to the proximal suspensory ligament (PSL) and 20 horses with findings nonrelated to tarsal pain. All horses underwent CT and radiographic examination. Images were reviewed by three independent observers who graded the severity and localization of findings. Bone-related categories as well as soft tissue-related categories were evaluated. For the comparison of imaging findings in horses with and without proximal suspensory desmitis (PSD), mixed linear regression was performed. The intraclass correlation coefficient (ICC) was calculated to assess intraobserver agreement, and kappa statistics were employed to evaluate interobserver agreement. CT examination identified significantly more abnormalities in the diseased group. The scores for osseous exostosis (p = .015) and PSL enlargement (p = .004) were notably higher in PSD horses compared to controls. Intraobserver agreement was overall high (ICC .82-1.0), and interobserver agreement was substantial for the detection of mineralization (kappa = .61) and moderate for sclerosis (kappa = .43), exostosis (kappa = .43), and PSL enlargement (kappa = .48/.51). Measurements in the soft tissue window were significantly smaller than those in the bone window. Findings concurrent with PSD including osseous proliferation and sclerosis as well as soft tissue enlargement, mineralization, and avulsion can be reliably detected using CT. Findings from the current study supported the use of CT for evaluating horses with suspected PSD where high-field MRI is not available.

First phalanx exostosis in traditional equestrian horses in Western Libya.

Background: Orthopedic diseases involving the forelimb fetlock joint of horses other than those used in professional racing have not been widely reported in the literature. One of these problems is the exostosis on the proximal forelimb phalanx (P1), which has not been reported previously in Western Libya. Aim: The study aimed to investigate the prevalence of P1 exostosis in traditional equestrian horses (known locally as Sarj horses) of different breeds in Libya that participated in a special social event and described its clinical findings radiographic appearance. Methods: The current study involved 60 horses admitted to private veterinary clinics with varied fetlock orthopedic problems. The studied horses were aged between 6 and 11 years old and galloped on hard grounds. Clinical and radiographic examinations were carried out on all horses. Lateromedial radiographs for one or both forelimb fetlock joints were acquired for each horse. Results: Clinical examination revealed that 21 horses (35%) had hard non-painful swelling on the dorsal aspect of fetlock with joint stiffness during flexion. In 19 of them, the swelling was bilateral. No forelimb lameness was noticed. Radiographically, hard swelling was diagnosed as bone exostosis, with various sizes, on the proximo-dorsal aspect of P1. There was also a new bone formation on the disto-dorsal part of third metacarpal bone in two cases. Conclusion: This study has documented the first report on bone exostosis on the proximo-dorsal aspect of the forelimb proximal phalanx as a common problem in Sarj horses that galloped on hard grounds in Western Libya. Although this bone lesion did not cause lameness in all reported cases, further investigations are warranted to identify its histopathological nature, potential etiology, and proper treatment.

Radiographic Description of a Bone Exostosis Lesion on the Caudal Aspect of the Proximal Tibia in Three Thoroughbred Yearlings (2014-2019).

This manuscript describes exostosis lesions originating from the caudal aspect of the proximal tibia identified in three Thoroughbred yearlings as part of the routine review of presale radiographic images. These lesions are hypothesized to be osteochondromas. The identification of bony exostoses on the proximal tibia has not been reported before in current literature. As they have not been described, the future effect on performance or soundness is unknown. Although these cases were not lame at the time of detection, the future growth of the lesion and its impact on surrounding soft tissues is unknown.

Laparoscopic resection of an exostosis of the os pubis in a horse.

OBJECTIVE: To report the diagnostic findings and laparoscopic removal of an exostosis of the os pubis in a horse. STUDY DESIGN: Case report. ANIMAL: One 12-year-old Black Forest draught gelding. METHODS: History included recurrent colic before and during urination and poor performance. Findings at rectal examination included a pointed osseous prominence adjacent to the symphysis of the pecten ossis pubis. Cystoscopy revealed that this prominence caused a protrusion of the bladder wall into the lumen. Standing laparoscopy and laparoscopy under general anesthesia were performed. RESULTS: After a failed attempt at standing laparoscopy, the horse was anesthetized, and the exostosis of the os pubis was removed laparoscopically without complications. No recurrence of clinical signs associated with the exostosis was detected 12 months postoperatively. CONCLUSION: Minimally invasive surgical resection of an exostosis of the os pubis was achieved under general anesthesia with appropriately designed instruments. This treatment alleviated symptoms associated with the exostosis, including potential injury of the urinary bladder wall.

Trauma-induced exostosis of multiple suture lines causing partial bilateral nasolacrimal duct obstruction in a 7-year-old Thoroughbred mare.

A definitive diagnosis of extensive suture line exostoses affecting the nasofrontal, nasolacrimal, nasomaxillary, frontolacrimal, lacrimozygomatic and lacrimomaxillary suture lines in a 7-year-old Thoroughbred mare with chronic bilateral epiphora and facial deformation was achieved using standing computed tomography (CT) examinations. Positive contrast dacryocystorhinography using CT revealed partial bilateral obstruction of the nasolacrimal ducts. Minimally displaced depression fractures of the right nasal bone, the right maxillary bone and right frontal bone were also demonstrated. The cosmetic appearance of the periosteal reaction associated with the suture line exostosis and epiphora significantly improved within 3 months of diagnosis and treatment.

Pathology in skeletons of Peale's dolphin Lagenorhynchus australis from southern South America.

Peale's dolphin Lagenorhynchus australis is frequently seen off the coast of southern South America, where it feeds among coastal kelp beds and occasionally strands. We searched for macroscopic evidence of skeletal lesions in 78 specimens of Peale's dolphin from 2 museum collections, which contain almost all of the species' skeletons known in collections worldwide. Thirty-two specimens (41%) had some type of osteological abnormalities. In 21 cases (66%), congenital deformations were the most predominant abnormality found. Acquired lesions included (1) induced trauma: abnormal curvature (n=5 specimens) and fractures (n=2); (2) infectious diseases: spondylo-osteomyelitis (n=3); and (3) degenerative diseases: exostoses (n=8) and spondylosis deformans (n=4). It is noteworthy that all of these animals died incidentally in gillnet entanglement and were presumably healthy at the time of death. The effect that different osseous lesions may have on an animal's quality of life may depend on the area of the spine affected and the number of vertebrae involved.

Mucoperiosteal exostoses in the tympanic bulla of African lions (Panthera leo).

Mucoperiosteal exostoses (MpEs) of the tympanic bulla (TB), also referred as middle-ear otoliths, have been occasionally described in dogs and cats in association with clinical signs of otitis media or as an incidental finding, but they have not been recorded in other species. In this report, we describe the radiographic, gross, and histopathologic features of MpEs in 8 African lions (Panthera leo). All animals (5 males and 3 females) were adults that had been kept in captivity and had their skeletons conserved as part of an anatomic academic collection. A radiographic study revealed mineralized structures in the TB consistent with MpEs in 7 of the 16 examined TB; a computed tomography study identified MpEs in 12 of the 16 TB. Six TB from 4 lions were sectioned, and several MpEs were demineralized for histopathologic analysis. Grossly, MpEs appeared variable in number and shape. Some were globular structures that were loosely attached to the mucosal surface of the TB; others were isolated to coalescent bone spicules extending from the mucoperiosteum. Position was also variable, but MpEs frequently developed in the hypotympanum, especially on the ventromedial aspect of the TB wall. Microscopically, MpEs were composed of osteonal bone growing from the periosteum and not by dystrophic calcification of necrotic tissue debris, as is hypothesized in dogs.

Exostoses on the palmar or plantar aspect of the diaphysis of the third metacarpal or metatarsal bone in horses: 16 cases (2001-2010).

OBJECTIVE: To characterize the clinical features, diagnostic procedures, treatment, and outcome for horses with an exostosis on the palmar or plantar cortex of the third metacarpal bone (MC3) or third metatarsal bone (MT3). DESIGN: Retrospective case series. ANIMALS: 16 horses. PROCEDURES: Records from 2001 through 2010 were evaluated to identify horses with radiographic and ultrasonographic evidence of an exostosis on an MC3 or MT3. Signalment, history, lameness examination results, diagnostic imaging results, surgical and histopathologic findings, treatment, and outcome were evaluated. RESULTS: 9 horses (group A) had unilateral lameness of the exostosis-affected limb that was alleviated with local or perineural analgesia. Seven horses (group B) had inconsistent lameness of the affected limb. The exostosis was located between the middle and distal third of the MC3 or MT3 in all horses. Desmopathy or peritendinous fibrosis (or both) of the suspensory ligament at the exostosis site was identified in 6 horses. All horses in group A returned to full function after conservative or surgical management. Lameness did not recur in any of the horses in group B despite no treatment or only conservative management. CONCLUSIONS AND CLINICAL RELEVANCE: Exostosis of the palmar cortex of an MC3 or plantar cortex of an MT3 should be considered as a cause of lameness in horses. The diagnosis can be made by the use of radiography and ultrasonography combined with specific diagnostic analgesia. Prognosis for return to athletic activity can be good but should be modified contingent on concurrent desmopathy of the suspensory ligament.

Imaging diagnosis--nasofrontal suture exostosis in a horse.

A 14-year-old Quarter Horse had chronic facial swelling and a more recent history of progressive bilateral epiphora. Radiographic findings were compatible with exostosis of the nasofrontal suture. Computed tomography (CT) of the head, including CT dacryorhinocystography, confirmed the diagnosis and allowed presurgical planning of resection of the exostosis, which resulted in resolution of the clinical signs.

Prevalence of anomalies in the appendicular skeleton of a fossorial rodent population.

The prevalence of macroscopic bone anomalies in the appendicular skeleton of wild rodents and, particularly, fossorial species is not well known. We examined 8,257 bones corresponding to 564 collection specimens (249 males and 315 females) of a fossorial form of water vole (Arvicola terrestris monticola). Animals were obtained monthly from July 1983 to December 1984 in the Aran Valley (Pyrenees). Most macroscopic anomalies were healed fractures or exostoses. The prevalence of anomalies was not significantly different between males and females but was clearly higher in adults than in juveniles and subadults. The frequency of alterations in the thoracic limb long bones was significantly higher than that in the pelvic counterparts. Aggressive intraspecific interactions and biomechanical factors related to burrowing may be associated with these differences. In females, remodeling of the innominate shape because of pregnancy and parturition could enhance fractures and exostoses in this structure.

Use of magnetic resonance imaging identify suspensory desmitis and adhesions between exostoses of the second metacarpal bone and the suspensory ligament in four horses.

Four horses were examined because of chronic forelimb lameness. In all horses, the cause of the lameness was localized to the metacarpus by means of physical examination and diagnostic anesthesia, and radiography of the affected limb revealed a small exostosis of the second metacarpal bone. Magnetic resonance imaging revealed suspensory desmitis in the region of this exostosis in all 4 horses. In addition, an abnormal area of low signal intensity, suggestive of an adhesion, was seen between the exostosis and the suspensory ligament. In all horses, an adhesion between the suspensory ligament and the exostosis on the second metacarpal bone was identified and transected at surgery, and the exostosis and distal portion of the second metacarpal bone were removed. All horses were able to return to their previous athletic use following a 6-month rest and rehabilitation program for treatment of the suspensory desmitis. Findings in these horses suggest that adhesions between the suspensory ligament and an exostosis of the second metacarpal bone may be a cause of chronic or recurrent forelimb lameness in horses.

Exostoses of the caudal perimeter of the radial physis as a cause of carpal synovial sheath tenosynovitis and lameness in horses: 10 cases (1999-2003).

OBJECTIVE: To determine the clinical, radiographic, ultrasonographic, and arthroscopic findings associated with tenosynovitis of the carpal synovial sheath induced by exostoses that originate from the caudal surface of the physeal scar of the distal radius and determine the results of surgical removal of those exostoses in horses. DESIGN: Retrospective study. ANIMALS: 10 horses. PROCEDURE: Medical records of horses with effusion in the carpal synovial sheath and lameness evaluated from 1999 to 2003 were examined. RESULTS: All horses had a history of intermittent mild to moderate effusion of the carpal synovial sheath and lameness of 1 forelimb. Results of regional perineural and intrathecal anesthesia of the carpal synovial sheath confirmed that the lameness originated in the carpal synovial sheath. Radiography revealed exostoses originating from the caudal cortex of the distal radius at the level of the closed physis. Arthroscopy was performed for confirmation and removal of exostoses that penetrated the carpal synovial sheath and impinged on the deep digital flexor tendon. All horses returned to previous athletic activity. One horse had a recurrence of clinical signs 12 months after surgery, which resolved with medical treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Tenosynovitis of the carpal synovial sheath and lameness were caused by impingement of exostoses of the caudal radius on the lining and contents of the carpal synovial sheath. Although the clinical signs and surgical treatment were similar to that caused by osteochondromas, these exostoses developed at the level of the closed physis of the distal radius and were not radiographically or histologically similar to osteochondromas.

Back-scattered electron imaging of a non-vertebral case of hypervitaminosis A in a cat.

We describe a clinical case of hypervitaminosis A in a cat. The main lesions were bony fusions of both the hip and stifle joints, without spinal involvement. A post-mortem study using back-scattered scanning electron microscopy (BEI-SEM) revealed that exostoses had formed around the joints without articular surface involvement. The more recently formed areas of bony proliferation were composed mainly of chondroid tissue surrounded by different degrees of woven bone. As the bony reaction occurred, remodelling of the trabeculae was observed which lead to progressive substitution of chondroid tissue by woven bone surrounded by apposition of lamellar bone. No traces of calcified cartilage were observed in any of the bone sections evaluated.

Excrescent lesion: a diagnosis of lateral talar exostosis in chronically symptomatic sprained ankles.

The excrescent lesion is a symptomatic anterolateral exostosis at the insertion of the anterior talofibular ligament. It is found in patients with chronic ankle pain after inversion injuries. It is most reliably diagnosed by computed tomography scan, but physical examination and oblique radiographs are suggestive in most cases. A technique for surgical excision and, in some cases, repair of the anterior talofibular ligament is described. Five patients having a history of inversion sprains of the ankle, without significant symptomatic improvement for a mean of 21 months after the injury, were evaluated. None had significant instability in the ankle or subtalar joints, clinically or with stress radiographs. The diagnosis of excrescent lesion was confirmed with computed tomography scan in all five patients. Each underwent excision of the exostosis. Removal of the exostosis produced laxity of the anterior talofibular ligament in four of the patients and required an additional modified Broström procedure to tighten the anterior talofibular ligament. Clinical results were evaluated at a mean of 33 months postoperatively, using the Ankle-Hindfoot scale from the American Orthopaedic Foot and Ankle Society. The three patients without pending claims for Workers' Compensation or related litigation all had excellent results (mean score, 93 points). Two patients with active legal claims had fair and poor results (mean score, 53 points).

Two outbreaks of fluorosis in cattle and sheep.

Two outbreaks of fluorosis in cattle and sheep were investigated in the Northern Transvaal. The animals exhibited severe dental lesions, lameness and exostoses. Plasma fluoride concentrations were high and there was an inversion of the albumin/globulin ratio. Alkaline phosphatase activity was elevated. Drinking water from boreholes contained excessive amounts of fluoride and upon irrigation, pastures were also contaminated with fluoride.

[The treatment of insertion desmopathy in the metatarsus of horses]. / Zur Behandlung der Insertionsdesmopathien am Mittelfuss des Pferdes.

Metacarpal or metatarsal exostoses were diagnosed in 112 horses used for sport purposes between January 1976 to December 1987. Fourteen of these patients were treated surgically by subperiosteal removal of the exostosis. All animals which could be followed up had returned to their original use. The average time of use after discharge from the clinic was 38.4 months. Surgery was successful in completely removing the exostoses in 58.3% of these horses. The indications for anaesthesia and resection of the ulnar nerve are discussed.

[Spavin in horses]. / Spat bij het paard.

The pathogenesis of bone spavin and its implications for diagnosis and therapy are reviewed. The pathogenesis of spavin can be divided into three phases, which are characterised by fibrillation of cartilage, osteolysis and ankylosis respectively. It will depend on the degree of osteolysis whether diagnostic anaesthesia should be added to standard clinical and radiological examinations. Satisfactory results of treatment in the group of patients with severe osteolysis can only be obtained by arthrodesis of the distal tarsal joints. It is expected that biomechanical investigations will provide a better understanding of the mechanical factors involved in the pathogenesis of spavin. For the time being, the only method of prevention will have to consist in strict selection and high-level rearing of the young horses.

[Hyperostosis of the mandibles in a West Highland white terrier]. / Hyperostosis van de mandibulae bij een West Highland white terrier.

A clinical case of craniomandibular osteopathy in a 7-month-old West Highland White Terrier is reported. The literature on the pathogenesis, clinical and radiological symptoms as well as the treatment and prognosis are briefly reviewed.