Modified toggle pin technique combined with prosthetic capsular reconstruction for surgical stabilization of coxofemoral luxation in a Shetland pony

Objective To describe open reduction and surgical stabilization of a coxofemoral luxation in a pony using a modified toggle pin technique and prosthetic joint capsule reconstruction without osteotomy of the greater trochanter. Animal A 2-year-old Shetland pony with a bodyweight of 167 kg. Study design Case report. Methods Radiographic examination confirmed craniodorsal luxation of the left coxofemoral joint. An open reduction with the aid of a pulley system was performed. A toggle pin was inserted through a bone tunnel extending from the level of the femoral shaft through the femoral head and the center of the acetabulum for the pin to be positioned on the medial wall of the acetabulum. FiberWire was subsequently passed through the cranial and caudal aspects of the acetabulum as well as a transverse tunnel in the femoral neck in a figure of 8 to facilitate capsular reconstruction. The pony was placed in a sling for 8 weeks and gradually returned to normal activity over 2 months. Results Postoperative radiographic examination confirmed the position of the femoral head in the acetabulum with the implants in place. On 2-year follow-up the pony was sound at walk and trot. Conclusion A combined intra- and extra-articular stabilization technique for coxofemoral luxation in a pony resulted in successful long-term reduction and excellent outcome

Die Obwegeser-Cerclagen-Technik für die Behandlung von Kieferfrakturen beim Pferd: Eine retrospektive Studie an 46 Fällen (1987–2010)

Skull fractures, particularly mandibular fractures, are the second most common fractures in horses after limb fractures. The majority of mandibular fractures involves its most rostral part, i.e. the pars incisiva. Like other head fractures, those of the jaws are commonly caused by a blunt external trauma such as a kick from another horse, a fall or a collision with a solid object. Rostral fractures can also occur when horses get caught between vertical metal bars in the stall: the horse bites the bar with its head tilted towards a slightly horizontal position and then suddenly pulls back its head together with a vertical movement of the head, while the teeth remain lodged between the metal bars. In rare cases jaw fractures occuriatrogenically following dental treatment or due to pathological alteration of the bone in case of neoplasia or chronic osteomyelitis. In the majority of cases jaw fractures are open toward the oral cavity and may be severely contaminated. Unstable, bilateral or dislocated fractures which lead to impaired occlusion need surgical intervention. Intraoral wiring is one of the fixation techniques used, depending on the fracture configuration. The Obwegeser multiple-loop intraoral wiring method is particularly suited for fixation of avulsion fractures of the incisors because teeth can be fixed individually, the tension can be distributed evenly among different teeth and the fixation can be extended across a wide area. This method is very suitable for fixation of rostral jaw fractures. It can also be used in combination with other fixation techniques, e.g. plate osteosynthesis, to provide additional stability on the tension side of a fractured mandible and incisor bone. This retrospective study examined 46 patients with jaw fractures that were fixed using the Obwegeser wiring method alone (n=31) or in conjunction with another fixation method (n=15). Medical records, repeated radiological examinations and telephone interviews with the owners were used to gather information about clinical signs on presentation, type of fracture fixation, the healing process, short and long term complications, time of removal of the wires and owner satisfaction with the surgical outcome. The following clinical signs were found with the initial examination: oral haemorrhage (n=28), dysphagia (n=24) and local swelling (n=21). 23 horses suffered from malocclusion and in 5 of 46 patients crepitation was obvious. In 20 cases (43%) the fracture was older than 24 hours at the time of presentation to the hospital. Forty (87%) of the fractures were open. Cases that were fixed using the Obwegeser wiring method alone had a lower complication rate (11/31, 35%) than cases in which wiring was used in conjunction with another fixation method (12/15, 80%). In most cases the fracture could be repaired in the standing horse using sedation and local anaesthesia. An orthopaedic stainless steel wire with a diameter of 1.25 mm was used for cerclage. Wires used alone were left in place for an average of 10 weeks (mean 10.0 and SD±5.8) and those used in addition to another fixation method for an average of 16 weeks (mean 16.0 and SD±8.9). No further complications associated with the fracture occurred in 31 (93%) of the 33 cases that had long-term follow-up information. The fact that in 20 cases (43%) the fracture was older than 24 hours at the time of presentation to the hospital shows that jaw fractures are commonly not recognized immediately or are underestimated by owners or referring veterinarians. The lower complication rate in the 31 cases treated with the Obwegeser wiring method alone may be explained by the lower complexity of the fractures, the intra- versus the extraoral position of the implants and thereby no possible interference of the implant with fracture healing, and the reduced amount of implant material. This study shows that the inexpensive and relatively simple Obwegeser method is a very suitable method for fixation of rostral jaw fractures in the horse

Kollateralbanderkrankungen am Sprunggelenk: Diagnostik, Prognose und Therapie

Die Seitenbänder des Tarsalgelenkes wurden lange Zeit nicht oder nur selten mit Lahmheitenassoziiert. Erkrankungen der Tarsalgelenkseitenbänder werden nach heutigem Kenntnisstandjedoch unterdiagnostiziert. Das Sprunggelenk des Pferdes ist sowohl bei Sport- als auch beiFreizeitpferden recht häufig Sitz unterschiedlicher orthopädischerProbleme. Die Tarsalgelenkseitenbänder (TGSB) wurden jedochlange Zeit in der Literatur nur sporadisch in Zusammenhang mitLahmheiten gebracht. Auch wenn Verletzungen dieser Bändersicher keine häufige Erkrankung in der Pferdeorthopädie darstellen,so kommen sie unserer Erfahrung nach doch regelmäßig vorund werden möglicherweise unterdiagnostiziert. Dies birgt die Gefahr,dass eine spezifische Therapie verpasst und damit die Prognoseverschlechtert wird. Es ist also lohnenswert, sich etwas nähermit den Charakteristika dieser Erkrankung aus orthopädischerSicht zu befassen

Ultrasonography of the long and short parts of the equine tarsocrural collateral ligament

The aim of this study was to determine the sonographic appearance especially of the short parts of the tibiotarsal collateral ligament in both extended and flexed limbs. Attention was given as to whether examination in either extension or flexion would change the appearance of and/or aid identification and assessment of the individual ligaments. Introduction: Tarsocrural collateral ligament (functional) anatomy and the appearance of collateral ligament injury as detected by different imaging modalities have been described in the literature. Methods: Seven pairs of tarsi of horses that had been euthanized for reasons other than hind limb lameness were isolated and prepared for sonography. Ultrasonography was performed using a linear high-frequency transducer. The long and short parts of the medial and lateral collateral ligaments of each specimen were examined in extension and flexion. Criteria for evaluation were visibility of origin, body and insertion of each individual ligament according to visibility of organized fibers and clear margins. Images were recorded of the origin, the body, and the insertion of each ligament and analyzed. Results: All the long collateral ligaments (n = 28) were imaged in all joints left and right, medially and laterally, and in extension and flexion. Overall, the three parts of the short collateral ligament were visualized more easily on the medial aspect of the limb, both in extension 76.6% and in flexion 87.8%. On the lateral aspect, 59.6% of the short collateral ligament was visualized in extension and only 54.4% in flexion. The middle part of the short collateral ligament was most consistently entirely imaged; in flexion 90% medially and 92% laterally and in extension 94.6% medially and 83.6% laterally. The profound part of the short collateral ligament was most difficult to visualize, its mid-part was imaged in 83.5% on the medial aspect in flexion. The mid-part of the short collateral ligament showed mild torsion of its fibers in extension (when it is relaxed) and parallel fiber arrangement in flexion. Imaging was hampered in some cases by subcutaneous and intrafascial gas accumulation due to the preparation of the specimens. Conclusions: Ultrasonographic examination allows identification of the individual subsections of the short tarsocrural collateral ligament. The long collateral ligament is comfortably identified and completely imaged. Flexion of the tarsus helps to identify the individual parts of the short collateral ligaments, especially on the medial aspect of the tarsus. It may be beneficial to scan the tarsocrural collateral ligaments in flexion especially if injury to the short part is suspected. Whether this applies to the live equine patient and to injured collateral ligaments too is currently under investigation

Locking compression plate osteosynthesis of complicated mandibular fractures in six horses

Complicated mandibular fractures were recognised in one foal, one pony and four horses. The foal was two months old while the adult animals ranged in age from 12 to 24 years. Three horses had a unilateral horizontal ramus fracture. Two fractures were open and one was closed. Comminution was present in one of these patients while lthe other two horses had marked displacement of the fragments. Two suffered from comminuted fractures of the horizontal and vertical ramus of the mandible. One of these patients had open and infected fractures. One foal had a bilateral horizontal ramus fracture with mrked periosteal "new bone" formation and malalignement which required corrective osteotomy. Each horse underwent locking compression plate (LCP) osteosynthesis consisting of open fracture reduction and application of one to three 4.5/5.0 mm LCP at the ventral, lateral or caudal aspect of the mandible under fluoroscopic control. Two 3.5 mm LCP were used in the foal. Plate fixation was supported by application of a cerclage wire construct between the incisor and premolar teeth in most patients. Complete fracture healing, with excellent functional and cosmetic outcome was achieved in all of the patients. Complications encountered included seroma formation, screw and wire breakage, as well as implant and apical tooth root infections. The LCP was removed after fracture healing had occurred in four patients

Diagnostic imaging, surgical treatment and histopathological findings of a vascular hamartoma in a 2-year-old horse

We describe a case of a 2-year-old mare that presented with a large firm swelling on the lateral aspect of the right tarsus. Diagnostic ultrasound demonstrated a fluid filled cavernous mass that was not clearly demarcated from the surrounding subcutaneous tissue. Contrast radiography with intralesional injection of contrast medium showed accumulation of the medium in the caverns of the mass and in the saphenous vein. Contrast enhanced computed tomography demonstrated 2 vascular meshes, one deep and one more superficially, closely associated with the mass. Surgical excision of the mass was performed and a vascular hamartoma was diagnosed based on histopathology. The horse showed no signs of recurrence 7 months after surgery