Pathological fracture through a subchondral bone cyst in the proximal phalanx of a horse

A 12‐year‐old Morgan broodmare presented for a nonweightbearing right forelimb lameness. Radiography and computed tomography confirmed the presence of a pathological fracture of the proximal first phalanx through a large subchondral bone cyst (SBC) in the right forelimb and a large SBC in the proximal first phalanx of the left forelimb. Surgical repair of the large palmar medial eminence fracture of the proximal first phalanx fracture was performed using bone screws placed in lag fashion placed through stab incisions after debridement and bone grafting of the SBCs. Approximately 6 months after surgery the mare was ambulating comfortably at pasture. This case report describes a fracture through a large subchondral bone cyst in a horse despite chronicity and ongoing bone remodelling. Careful consideration regarding exercise or use should be considered in horses with large SBCs.     

Diagnosis and surgical management of a subchondral bone cyst within the intermediate tubercle of the humerus in a horse

The case of a horse with a subchondral bone cyst in the lateral slope of the intermediate humeral tubercle is presented. Diagnosis was complicated by the unusual location and subsequent challenge in imaging the cyst. Endoscopic debridement resulted in a good outcome.     

Navicular bone fractures in the horse

Avulsion fractures from the distal border of the navicular bone are relatively common, but normally of little clinical significance. Other fractures are uncommon and have a poor prognosis. Surgical fixation of parasagittal fractures (lag screw) is technically quite difficult, but potentially improves the prognosis for return to work to about 80%. If surgical fixation is not possible, then farriery to raise the heels of the foot may be of benefit.     

Mandibular condylectomy in a standing horse for treatment for osteoarthritis of the temporomandibular joint

An Irish Sport Horse mare presented for evaluation and treatment of inability to masticate effectively with subsequent severe weight loss. A slowly expanding, firm, nonpainful mass was noted at the left temporomandibular joint. Radiographic examination revealed extensive osteoarthritic changes of this joint. Due to the age and debilitated condition of the horse, along with financial constraints on the owner's behalf, the decision was made to perform a mandibular condylectomy as a standing procedure using sedation and local and regional anaesthesia techniques. The mare tolerated the procedure very well and post operatively improved significantly.     

Standing removal of the proximal aspect of an olecranon fracture in a mature horse

A 12‐year‐old 450 kg Argentine polo mare presented with a dropped elbow and an unwillingness to bear weight after being kicked by another horse on the lateral aspect of the upper left forelimb. The mare was subsequently diagnosed with a displaced olecranon fracture that did not readily conform to the standard classification systems. Referral for surgical treatment involving open reduction and internal fixation was declined due to financial constraints. Due to the mare being unsuitable for breeding, and conservative treatment of displaced olecranon fractures being deemed to have an overall poor prognosis for return to full athletic performance, another treatment option was sought. Given the fracture configuration, standing surgical removal of the large proximal fragment was performed. The mare returned to full athletic performance 12 months post operatively without lameness. This case report describes an alternative treatment option for selected olecranon fractures.     

Arthroscopic guided repair of a slab fracture of the fourth carpal bone in an 8-month-old thoroughbred horse

An 8-month-old thoroughbred colt presented with sudden onset right forelimb lameness. A radiographic series of the right carpus was performed, and it revealed a slab fracture of the fourth carpal bone and fracture of the proximal part of the third metacarpal bone. Arthroscopically guided repair of the slab fracture of the fourth carpal bone with a 3.5 mm cortex screw and lag screw fixation of the fracture of the proximal part of the third metacarpal bone were performed. The horse started to race at 32 months old and started in 65 races over three years without any trouble associated with the right carpus.     

Short‐ and long‐term results following standing fracture repair in 34 horses

Reasons for performing study: Standing fracture repair in the horse is a recently described surgical procedure and currently there are few follow‐up data. This case series contains 2 novel aspects in the standing horse: repair of incomplete sagittal fractures of the proximal phalanx and medial condylar repair from a lateral aspect. Objectives: To describe outcome in a case series of horses that had lower limb fractures repaired under standing sedation at Rossdales Equine Hospital. Method: Case records for all horses that had a fracture surgically repaired, by one surgeon at Rossdales Equine Hospital, under standing sedation and local anaesthesia up until June 2011, were retrieved. Hospital records, owner/trainer telephone questionnaire and the Racing Post website were used to evaluate follow‐up. Results: Thirty‐four horses satisfied the inclusion criteria. Fracture sites included the proximal phalanx (incomplete sagittal fracture, n = 14); the third metacarpal bone (lateral condyle, n = 12, and medial condyle, n = 7); and the third metatarsal bone (lateral condyle, n = 1). One horse required euthanasia due to caecal rupture 10 days post operatively. Twenty horses (66.7% of those with available follow‐up) have returned to racing. Where available, mean time from operation to return to racing was 226 days (range 143–433 days). Conclusions: Standing fracture repair produced similar results to fracture repair under general anaesthesia in terms of both the number of horses that returned to racing and the time between surgery and race. Potential relevance: Repair of lower limb fracture in the horse under standing sedation is a procedure that has the potential for tangible benefits, including avoidance of the inherent risks of general anaesthesia. The preliminary findings in this series of horses are encouraging and informative when discussing options available prior to fracture repair.     

A technique for computed tomography (CT) of the foot in the standing horse

Computed tomography (CT) in equine orthopaedics is currently limited because of the price, availability, impossibility to transport the scanner into surgical theatre, and the contraindications of general anaesthesia in some patients. A pQCT (peripheral quantitative computerised tomography) scanner was designed by the authors to image the limbs of the horse, both in standing or recumbent position. Standing computed tomography of the foot with a pQCT scanner is feasible and well tolerated by the horse. It enables good visualisation of bony structures but is not suitable to evaluate soft tissues. The technique can also assist surgery by assessing the 3D configuration of bone lesions.     

Treatment of incisive bone fracture in a horse using an acrylic splint

A ventrally displaced incisive bone fracture was diagnosed in a 3-year-old Andalusian stallion. Symptoms included swelling of the lips, dysphagia and ptyalism. External manipulation revealed pain and crepitus in the gingival region of the rostral maxilla. An intraoral examination revealed upper gingival haematomas, misalignment and malocclusion of the incisors (prognathism). A radiograph of the rostral maxilla confirmed ventrally displaced bilateral fractures of the incisive portion of the maxilla rostral to the canine teeth (Triadan 104/204). The fracture was reduced under general anaesthesia. A methylmethacrylate intraoral splint was used to stabilise the fracture. Post operative radiographs confirmed the fracture reduction. Post operative clinical control confirmed the correct position of the splint. No complications were encountered in the post operative period and good stabilisation was obtained. The splint was removed 60 days post operatively. The use of an acrylic intraoral splint successfully stabilised a bilateral, ventrally displaced incisive bone fracture. Normal occlusion was obtained. The use of an acrylic splint may represent a relatively simple, inexpensive and noninvasive technique for the repair of incisive bone fractures rostral to canine teeth in horses.     

Conservative management of comminuted central tarsal bone fracture and joint instability in a horse

A comminuted fracture of the central tarsal bone, fragmentation of the fourth tarsal bone and associated joint instability was diagnosed in a 14‐year‐old Sport Horse mare who presented for investigation of acute nonweightbearing hindlimb lameness. The mare responded well to conservative management and, unlike previously reported cases of similar injuries, returned to a similar level of athletic activity.     

Computed tomography assisted repair of a central tarsal bone slab fracture in a horse

A 13‐year‐old Quarter Horse gelding was presented for repair of a central tarsal bone fracture. Radiographs showed a single large nondisplaced sagittal slab fracture; however, computed tomography (CT) revealed an additional small, displaced central tarsal bone fragment. The complex fracture was repaired, under the same anaesthetic period as the CT examination, using the CT hard copies images, intraoperative fluoroscopy and radiographs. The horse recovered well and after rehabilitation showed no residual lameness at work. Computed tomography was instrumental in achieving precise screw placement and successful fracture repair.     

Standing repair of a proximal,incomplete, articular fracture of the third metatarsal bone

A 5-year-old National Hunt Thoroughbred mare presented with sudden onset left hindlimb lameness after race training on the gallops. Clinical examination revealed a marked painful reaction over the proximal metatarsal region but no other obvious abnormalities were detected. Survey radiographs at the yard did not reveal any abnormalities. Nuclear scintigraphic examination 3 days after injury revealed focal marked increased radiopharmaceutical uptake in the proximal metatarsal region. Subsequent radiography revealed an incomplete, articular fracture of the proximal left third metatarsal bone. Repair of the fracture using 3 × 4.5 mm cortical screws placed in lag fashion was performed under standing sedation following perineural analgesia. Follow-up radiographs demonstrated progressive healing of the fracture. The mare returned to race training 8 months after the fracture was repaired and raced successfully 12 months post injury.     

Treatment of a second carpal bone fracture by removal under ultrasonographic guidance in a horse

OBJECTIVE: To report an unusual 2nd carpal bone (C2) slab fracture and its treatment, using an ultrasonographically assisted, minimally invasive arthrotomy technique, for fragment removal. STUDY DESIGN: Case report. ANIMALS: An 11-year-old crossbred Warmblood gelding. METHODS: A bone fragment, spanning the height of C2, identified on the palmaromedial aspect of C2 was demarcated intraoperatively using ultrasonographically guided needles and removed by arthrotomy. RESULTS: Fracture fragment removal was achieved using a small, ultrasonographically guided arthrotomy. The horse has become sound after treatment and returned to the previous level of pleasure riding activity. CONCLUSIONS: Perioperative ultrasonography was used to delineate and facilitate removal of an unusual slab fragment of C2, through a minimally sized arthrotomy. Despite the presence of pancarpal osteoarthritis and partial involvement of the medial collateral ligament, the prognosis appeared to be satisfactory for this pleasure riding horse. CLINICAL RELEVANCE: Ultrasonographic guidance may be used to optimize the approach to C2 articular bony fragments that may not be observed using arthroscopy.     

Bilateral hypoplasia of the minor tubercle of the humerus with medial luxation of the biceps tendon in two Quarter Horses

Two Quarter Horses were examined at the Washington State University Veterinary Teaching Hospital with forelimb lameness. Case 1 was a 4‐year‐old female with a 4 month history of intermittent forelimb lameness that had partially responded to oral anti‐inflammatories. The horse was in full training and actively competing in cutting. Case 2 was a one‐year‐old filly bred for cutting that presented with a right forelimb lameness of 3 weeks’ duration, which was not responsive to oral anti‐inflammatories. The horse was not in training. On lameness examination, Case 1 was grade 1/5 (American Association of Equine Practitioners scale) lame in the left forelimb in a straight line on a hard surface, extension and flexion of the shoulder was resented and exacerbated the lameness. Case 2 was grade 3/5 lame in the right forelimb in a straight line on a hard surface, flexion and extension of the shoulder was resented and exacerbated the lameness. Both horses had a characteristic dished appearance to the dorsal aspect of the shoulder, with prominence of the proximal aspect of the humerus. Ultrasound and proximodistal oblique (skyline) radiographic views of the scapulohumeral joints demonstrated bilateral hypoplasia of the minor tubercle of the humerus with bilateral medial luxation of the proximal biceps tendon in both cases. To the authors' knowledge this is the first report of 2 cases of bilaterally affected horses, as well as the first report of the condition in the Quarter Horse breed.     

Occult metastatic intestinal adenocarcinoma resulting in pathological fracture of the proximal humerus

Intestinal adenocarcinomas are rare but have been described in the literature. The present case is unusual in both its clinical presentation and in the distribution of metastatic lesions. The sequestrum formation and pathological fracture present are most commonly associated with osteomyelitis in horses and the details of the case highlight the need for differential diagnosis in these particular circumstances and of which clinicians should be aware.     

Use of computed tomography to evaluate a fracture associated with a subchondral pedal bone cyst in a horse

The radiological examination of bone lesions can be challenging, considering the complex superimposition of the 3D anatomy of a region on to a 2D image. This report describes the findings achievable with different diagnostic imaging modalities (radiography, arthrography, spiral computed tomography) and the correlation with the post mortem and histopathological findings in a horse with a fracture associated with an osseous cyst‐like lesion in the third phalanx. CT was highly superior to radiography to evaluate the spatial configuration and completeness of the fracture, relationship between the fracture and osseous cyst‐like lesion, architecture of the cyst, presence of its communication with the joint and secondary degenerative joint disease. In conclusion, CT represents an asset in these cases for an accurate prognosis and therapy.     

Desmectomy of a septic accessory ligament of the deep digital flexor tendon in the hindlimb of a horse under standing sedation

A horse presented with a discharging wound over the proximal aspect of the right metatarsal region. Examination, radiography and ultrasonography diagnosed a septic process within the accessory ligament of the deep digital flexor tendon (ALDDFT). Due to previous unsuccessful treatment with systemic antibiotics as well as financial restrictions, an ALDDFT desmectomy was performed with the patient under standing sedation and local analgesia. Histopathology confirmed the septic process within the affected structure. The patient made a rapid recovery and was discharged from the hospital 7 days post operatively and 2 years later was still in full work. This report describes the first case of infective hindlimb ALDDFT and the first desmectomy of this structure performed under standing sedation.