FRACTURES OF THE PROXIMAL HUMERUS


 FRACTURES OF THE PROXIMAL

HUMERUS

Fractures of the proximal humerus usually occur after

middle age and most of the patients are osteoporotic,

postmenopausal women.

-Mechanism of injury

Fracture usually follows a fall on the out-stretched

arm . the type of injury which, in younger people,

might cause dislocation of the shoulder. Sometimes,

indeed, there is both a fracture and a dislocation

Classification

-Neer

(1970) who drew attention to the four major segments

involved in these injuries: the head of the

humerus, the lesser tuberosity, the greater tuberosity

and the shaft

-###Neer's classification distinguishes

between the number of displaced fragments, with displacement

defined as greater than 45 degrees of angulation

or 1 cm of separation. Thus, however many fracture

lines there are, if the fragments are undisplaced it

is regarded as a one-part fracture; if one segment is separated from the others, it is a two-part fracture; if two

fragments are displaced, that is a three-part fracture; if

all the major parts are displaced, it is a four-part fracture.

(a)
                                                                                  (b)



 Fractures of the
proximal humerus Diagram of
(a) the normal and (b) a fractured
proximal humerus, showing the
four main fragments, two or
more of which are seen in almost
all proximal humeral fractures.
1=shaft of humerus; 2=head of
humerus; 3=greater tuberosity;
4=lesser tuberosity. In this figure
there is a sizeable medial calcar
spike; 5=suggesting a low risk of
avascular necrosis

Clinical features

-pain may not be severe.

-the appearance of a large bruise on the upper part of the arm.

X-ray

elderly patients there often appears to be a single,

impacted fracture extending across the surgical neck.

In younger patients, the fragments

are usually more clearly separated.

Treatment:-

MINIMALLY DISPLACED FRACTURES

need no treatment

apart from a week or two period of rest with the

arm in a sling until the pain subsides, and then gentle

passive movements of the shoulder.

after 6 weeks), active exercises are

encouraged

TWO-PART FRACTURES

Surgical neck fractures The fragments are gently

manipulated into alignment and the arm is immobilized

in a sling for about four weeks or until the fracture

feels stable and the x-ray shows some signs of

healing. Elbow and hand exercises are encouraged

throughout this period; shoulder exercises are commenced

at about four weeks. The results of conservative

treatment are generally satisfactory, considering

that most of these patients are over 65 and do not

demand perfect function. However, if the fracture

cannot be reduced closed or if the fracture is very

unstable after closed reduction, then fixation is

required. Options include percutaneous pins, bone

sutures, intramedullary pins with tension band wiring

Greater tuberosity fractures Fracture:- of the greater

tuberosity is often associated with anterior dislocation

and it reduces to a good position when the shoulder is

relocated. If it does not reduce, the fragment can be

re-attached through a small incision with interosseous

sutures or, in young hard bone,

THREE-PART FRACTURES

These usually involve displacement of the surgical

neck and the greater tuberosity.

FOUR-PART FRACTURES FRACTURES

-The surgical neck and both tuberosities are displaced.

These are severe injuries with a high risk of complications

such as vascular injury, brachial plexus damage, injuries

of the chest wall and (later) avascular necrosis of

the humeral head. Often

the most one can say is that there are multiple displaced

fragments, sometimes together with glenohumeral

dislocation. In young patients an attempt

should be made at reconstruction. In older patients,

closed treatment and attempts at open reduction and

fixation can result in continuing pain and stiffness and

additional surgical treatment can compromise the

blood supply still further.

-treartment of choice is prosthetic

replacement of the proximal humerus.

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