What Is a Proximal Humerus Fracture?

Neer classification of proximal humerus fractures is a four-part classification of the proximal humerus fractures that Neer proposed in 1970.

Neer classification of proximal humerus fractures

Neer classification of proximal humerus fractures is a four-part classification of the proximal humerus fractures that Neer proposed in 1970.

Chinese name

Neer classification of proximal humerus fractures

Foreign name

Neer classification

Presenter

Neer

Presentation time

1970

Classification basis

Humeral head, large nodule, small nodule, upper humerus

basic type

Type I, Type II, Type III, Type IV, Type V, Type VI

The 4 components of the upper end of the humerus, namely the humeral head, the large tuberosity, the small tuberosity and the upper humerus (joint or anatomical neck, large tuberosity, small tuberosity, backbone or surgical neck) are shifted into 6 basic types , Displacement> 1 cm or angle> 45 °, otherwise it cannot be considered as displacement bone.

Type I: Mild displacement fracture The upper end of the humerus can be a fracture (such as a single humeral surgical neck fracture, a single large nodule fracture or a small nodule fracture, etc.), or multiple fractures, that is, there are two or two at the same time Fractures at the above sites (such as surgical neck fractures with large nodular fractures, etc.), but the displacement of any fracture is not greater than 1 cm, and the angle of the bone end is not greater than 45 °. From the perspective of pathological damage, this kind of fracture soft tissue damage is light, or there is a close intercalation between the bone ends, the fracture is relatively stable, and generally the fracture heals quickly. This type of fracture accounts for the vast majority of fractures of the upper humerus. This kind of fracture without obvious displacement is called "partial fracture" because there is still soft tissue connecting the fracture pieces into one body.

Type II: A joint displacement fracture is named after the anatomical part of the humeral anatomical neck fracture, and the displacement between the bone ends is greater than 1 cm or the angle is greater than 45 °. The blood circulation of the fractured humeral head is disrupted, and ischemic necrosis of the humeral head often occurs. Such a fracture is a "two-part fracture" because of obvious displacement (or minor displacement of large and small nodules at the same time), which causes the humeral head to form two separate parts from the upper end of the humeral shaft.

Type III: A backbone fracture is named a surgical neck fracture from the anatomy. Fracture displacement greater than 1 cm or angular deformity greater than 45 °. A single backbone is displaced, and the upper end of the humerus is divided into two separate parts, so it is also a "two-part fracture". If a nodule fracture is closed at the same time and the displacement is more than 1 cm, the upper end of the humerus is divided into three separate parts, so it should be a "three-part fracture". For example, if the fractures of two nodules are closed at the same time, and both have a displacement of more than 1 cm, the upper end of the humerus is divided into four separate bone pieces, namely the humeral head, large nodule, small nodule, and upper humeral shaft. This fracture belongs to the "four-part fracture".

Type IV: Large tuberosity fractures Large tuberosity fractures with displacement greater than 1 cm. The large nodule has three faces that serve as attachment points for the superior, inferior, and small round muscles. Trauma can cause displacement of the entire large tuberosity fracture, or avulsion fractures on one side of the large tuberosity. If it is a partial avulsion fracture with obvious displacement, it means that the rotator cuff has a longitudinal tear. If a large tuberosity fracture is accompanied by a displacement of the surgical neck, the joint bones will be internally rotated by the scapularis muscle attached to the small tuberosity.

Type V: Small nodule displacement fractures can be avulsion fractures of small nodules alone. The displacement is more than 1 cm, which is a "two-part fracture". If there is a surgical neck fracture with significant displacement at the same time, it is a "three-part fracture". At this time, the joint segment is only pulled by the rotator cuff attached to the large nodule, so abduction and external rotation displacement can occur.

Type VI: Fracture of the upper humerus with dislocation of the humerus joint. Fracture and dislocation of the upper humerus refers to the fracture of the upper humerus and the true complete dislocation of the glenohumeral joint, not the rotational displacement of the humeral head or the subluxation in the joint. In cases of "two-part" or "three-part augmentation and dislocation", the humeral head may still have a certain blood circulation. If the "four-part" fracture and dislocation occurs, the blood circulation of the humeral head is damaged, which may easily cause ischemic necrosis of the humeral head.