Manubrium sterni (Sternebra I)
The manubrium is the most cranial sternebra. It is laterally compressed and bears the articular surfaces for the first pair of costal cartilages. It anchors the cranial ribs and provides attachment for pectoral and sternal muscles. It supports the base of the neck. With age the sternebrae tend to fuse.
The sternum is imaged with ventral ultrasound. Sternal fractures are rare but can occur from falls or trauma. Girth pressure can irritate the overlying soft tissues.
## Overview Sternal fracture is a break of the breastbone from direct ventral trauma such as a fall or collision. It causes ventral chest pain, crepitus, reluctance to lie down, pain when girthed, an
## Overview A pectoral abscess is a collection of pus in the chest muscles between the forelimbs. The classic cause in the western United States is Corynebacterium pseudotuberculosis (pigeon fever),
Check girth fit to avoid pressure sores. Chest pain or reluctance to move after a fall should be evaluated.
## Overview Sternal fracture is a break of the breastbone from direct ventral trauma such as a fall or collision. It causes ventral chest pain, crepitus, reluctance to lie down, pain when girthed, and sometimes ventral edema. Multiple sternebrae may be involved. ## Causes Blunt trauma to the ventral chest. ## Diagnosis Palpation and radiographs or ultrasound of the sternum. ## Treatment Rest and pain management. Surgical repair is rarely performed. Most heal with time. ## Recovery and Prognosis Good for uncomplicated fractures. ## Prevention Trauma avoidance. Signs include: ventral chest pain; crepitus on palpation; reluctance to lie down; pain when girthed; ventral edema
## Overview A pectoral abscess is a collection of pus in the chest muscles between the forelimbs. The classic cause in the western United States is Corynebacterium pseudotuberculosis (pigeon fever), producing large, painful swellings. Injection reactions can also cause abscesses. Horses show heat, pain, fever, and stiff forelimb movement. ## Causes Corynebacterium pseudotuberculosis or other bacteria introduced by wounds or injections. ## Diagnosis Clinical appearance, ultrasound, and culture of aspirated pus. ## Treatment Allow the abscess to mature, then lance and drain. Antibiotics are used in some cases. Hot packing helps maturation. ## Recovery and Prognosis Good for external abscesses once drained. ## Prevention Fly control and wound management in endemic areas. Signs include: hot painful swelling in the chest; reluctance to move the forelimbs; possible draining tract; fever; stiff gait
The sternum is imaged with ventral ultrasound. Sternal fractures are rare but can occur from falls or trauma. Girth pressure can irritate the overlying soft tissues.
Check girth fit to avoid pressure sores. Chest pain or reluctance to move after a fall should be evaluated.
See the Manubrium (First Sternebra) on our interactive 3D horse model. Open 3D Model